#include <linux/module.h>
#include <linux/fs.h>
#include <linux/time.h>
-#include <linux/ext4_jbd2.h>
#include <linux/jbd2.h>
#include <linux/highuid.h>
#include <linux/pagemap.h>
#include <linux/string.h>
#include <linux/buffer_head.h>
#include <linux/writeback.h>
+#include <linux/pagevec.h>
#include <linux/mpage.h>
+#include <linux/namei.h>
#include <linux/uio.h>
#include <linux/bio.h>
+#include <linux/workqueue.h>
+
+#include "ext4_jbd2.h"
#include "xattr.h"
#include "acl.h"
+#include "ext4_extents.h"
+
+#include <trace/events/ext4.h>
+
+#define MPAGE_DA_EXTENT_TAIL 0x01
+
+static inline int ext4_begin_ordered_truncate(struct inode *inode,
+ loff_t new_size)
+{
+ return jbd2_journal_begin_ordered_truncate(
+ EXT4_SB(inode->i_sb)->s_journal,
+ &EXT4_I(inode)->jinode,
+ new_size);
+}
+
+static void ext4_invalidatepage(struct page *page, unsigned long offset);
/*
* Test whether an inode is a fast symlink.
* "bh" may be NULL: a metadata block may have been freed from memory
* but there may still be a record of it in the journal, and that record
* still needs to be revoked.
+ *
+ * If the handle isn't valid we're not journaling, but we still need to
+ * call into ext4_journal_revoke() to put the buffer head.
*/
int ext4_forget(handle_t *handle, int is_metadata, struct inode *inode,
- struct buffer_head *bh, ext4_fsblk_t blocknr)
+ struct buffer_head *bh, ext4_fsblk_t blocknr)
{
int err;
BUFFER_TRACE(bh, "enter");
jbd_debug(4, "forgetting bh %p: is_metadata = %d, mode %o, "
- "data mode %lx\n",
+ "data mode %x\n",
bh, is_metadata, inode->i_mode,
test_opt(inode->i_sb, DATA_FLAGS));
BUFFER_TRACE(bh, "call ext4_journal_revoke");
err = ext4_journal_revoke(handle, blocknr, bh);
if (err)
- ext4_abort(inode->i_sb, __FUNCTION__,
+ ext4_abort(inode->i_sb, __func__,
"error %d when attempting revoke", err);
BUFFER_TRACE(bh, "exit");
return err;
*/
static int try_to_extend_transaction(handle_t *handle, struct inode *inode)
{
- if (handle->h_buffer_credits > EXT4_RESERVE_TRANS_BLOCKS)
+ if (!ext4_handle_valid(handle))
+ return 0;
+ if (ext4_handle_has_enough_credits(handle, EXT4_RESERVE_TRANS_BLOCKS+1))
return 0;
if (!ext4_journal_extend(handle, blocks_for_truncate(inode)))
return 0;
* so before we call here everything must be consistently dirtied against
* this transaction.
*/
-static int ext4_journal_test_restart(handle_t *handle, struct inode *inode)
+ int ext4_truncate_restart_trans(handle_t *handle, struct inode *inode,
+ int nblocks)
{
+ int ret;
+
+ /*
+ * Drop i_data_sem to avoid deadlock with ext4_get_blocks At this
+ * moment, get_block can be called only for blocks inside i_size since
+ * page cache has been already dropped and writes are blocked by
+ * i_mutex. So we can safely drop the i_data_sem here.
+ */
+ BUG_ON(EXT4_JOURNAL(inode) == NULL);
jbd_debug(2, "restarting handle %p\n", handle);
- return ext4_journal_restart(handle, blocks_for_truncate(inode));
+ up_write(&EXT4_I(inode)->i_data_sem);
+ ret = ext4_journal_restart(handle, blocks_for_truncate(inode));
+ down_write(&EXT4_I(inode)->i_data_sem);
+
+ return ret;
}
/*
* Called at the last iput() if i_nlink is zero.
*/
-void ext4_delete_inode (struct inode * inode)
+void ext4_delete_inode(struct inode *inode)
{
handle_t *handle;
+ int err;
+ if (ext4_should_order_data(inode))
+ ext4_begin_ordered_truncate(inode, 0);
truncate_inode_pages(&inode->i_data, 0);
if (is_bad_inode(inode))
goto no_delete;
- handle = start_transaction(inode);
+ handle = ext4_journal_start(inode, blocks_for_truncate(inode)+3);
if (IS_ERR(handle)) {
+ ext4_std_error(inode->i_sb, PTR_ERR(handle));
/*
* If we're going to skip the normal cleanup, we still need to
* make sure that the in-core orphan linked list is properly
}
if (IS_SYNC(inode))
- handle->h_sync = 1;
+ ext4_handle_sync(handle);
inode->i_size = 0;
+ err = ext4_mark_inode_dirty(handle, inode);
+ if (err) {
+ ext4_warning(inode->i_sb, __func__,
+ "couldn't mark inode dirty (err %d)", err);
+ goto stop_handle;
+ }
if (inode->i_blocks)
ext4_truncate(inode);
+
+ /*
+ * ext4_ext_truncate() doesn't reserve any slop when it
+ * restarts journal transactions; therefore there may not be
+ * enough credits left in the handle to remove the inode from
+ * the orphan list and set the dtime field.
+ */
+ if (!ext4_handle_has_enough_credits(handle, 3)) {
+ err = ext4_journal_extend(handle, 3);
+ if (err > 0)
+ err = ext4_journal_restart(handle, 3);
+ if (err != 0) {
+ ext4_warning(inode->i_sb, __func__,
+ "couldn't extend journal (err %d)", err);
+ stop_handle:
+ ext4_journal_stop(handle);
+ goto no_delete;
+ }
+ }
+
/*
* Kill off the orphan record which ext4_truncate created.
* AKPM: I think this can be inside the above `if'.
*/
static int ext4_block_to_path(struct inode *inode,
- ext4_lblk_t i_block,
- ext4_lblk_t offsets[4], int *boundary)
+ ext4_lblk_t i_block,
+ ext4_lblk_t offsets[4], int *boundary)
{
int ptrs = EXT4_ADDR_PER_BLOCK(inode->i_sb);
int ptrs_bits = EXT4_ADDR_PER_BLOCK_BITS(inode->i_sb);
int n = 0;
int final = 0;
- if (i_block < 0) {
- ext4_warning (inode->i_sb, "ext4_block_to_path", "block < 0");
- } else if (i_block < direct_blocks) {
+ if (i_block < direct_blocks) {
offsets[n++] = i_block;
final = direct_blocks;
- } else if ( (i_block -= direct_blocks) < indirect_blocks) {
+ } else if ((i_block -= direct_blocks) < indirect_blocks) {
offsets[n++] = EXT4_IND_BLOCK;
offsets[n++] = i_block;
final = ptrs;
final = ptrs;
} else {
ext4_warning(inode->i_sb, "ext4_block_to_path",
- "block %lu > max",
- i_block + direct_blocks +
- indirect_blocks + double_blocks);
+ "block %lu > max in inode %lu",
+ i_block + direct_blocks +
+ indirect_blocks + double_blocks, inode->i_ino);
}
if (boundary)
*boundary = final - 1 - (i_block & (ptrs - 1));
return n;
}
+static int __ext4_check_blockref(const char *function, struct inode *inode,
+ __le32 *p, unsigned int max)
+{
+ __le32 *bref = p;
+ unsigned int blk;
+
+ while (bref < p+max) {
+ blk = le32_to_cpu(*bref++);
+ if (blk &&
+ unlikely(!ext4_data_block_valid(EXT4_SB(inode->i_sb),
+ blk, 1))) {
+ ext4_error(inode->i_sb, function,
+ "invalid block reference %u "
+ "in inode #%lu", blk, inode->i_ino);
+ return -EIO;
+ }
+ }
+ return 0;
+}
+
+
+#define ext4_check_indirect_blockref(inode, bh) \
+ __ext4_check_blockref(__func__, inode, (__le32 *)(bh)->b_data, \
+ EXT4_ADDR_PER_BLOCK((inode)->i_sb))
+
+#define ext4_check_inode_blockref(inode) \
+ __ext4_check_blockref(__func__, inode, EXT4_I(inode)->i_data, \
+ EXT4_NDIR_BLOCKS)
+
/**
* ext4_get_branch - read the chain of indirect blocks leading to data
* @inode: inode in question
*err = 0;
/* i_data is not going away, no lock needed */
- add_chain (chain, NULL, EXT4_I(inode)->i_data + *offsets);
+ add_chain(chain, NULL, EXT4_I(inode)->i_data + *offsets);
if (!p->key)
goto no_block;
while (--depth) {
- bh = sb_bread(sb, le32_to_cpu(p->key));
- if (!bh)
+ bh = sb_getblk(sb, le32_to_cpu(p->key));
+ if (unlikely(!bh))
goto failure;
- add_chain(++p, bh, (__le32*)bh->b_data + *++offsets);
+
+ if (!bh_uptodate_or_lock(bh)) {
+ if (bh_submit_read(bh) < 0) {
+ put_bh(bh);
+ goto failure;
+ }
+ /* validate block references */
+ if (ext4_check_indirect_blockref(inode, bh)) {
+ put_bh(bh);
+ goto failure;
+ }
+ }
+
+ add_chain(++p, bh, (__le32 *)bh->b_data + *++offsets);
/* Reader: end */
if (!p->key)
goto no_block;
static ext4_fsblk_t ext4_find_near(struct inode *inode, Indirect *ind)
{
struct ext4_inode_info *ei = EXT4_I(inode);
- __le32 *start = ind->bh ? (__le32*) ind->bh->b_data : ei->i_data;
+ __le32 *start = ind->bh ? (__le32 *) ind->bh->b_data : ei->i_data;
__le32 *p;
ext4_fsblk_t bg_start;
ext4_fsblk_t last_block;
ext4_grpblk_t colour;
+ ext4_group_t block_group;
+ int flex_size = ext4_flex_bg_size(EXT4_SB(inode->i_sb));
/* Try to find previous block */
for (p = ind->p - 1; p >= start; p--) {
* It is going to be referred to from the inode itself? OK, just put it
* into the same cylinder group then.
*/
- bg_start = ext4_group_first_block_no(inode->i_sb, ei->i_block_group);
+ block_group = ei->i_block_group;
+ if (flex_size >= EXT4_FLEX_SIZE_DIR_ALLOC_SCHEME) {
+ block_group &= ~(flex_size-1);
+ if (S_ISREG(inode->i_mode))
+ block_group++;
+ }
+ bg_start = ext4_group_first_block_no(inode->i_sb, block_group);
last_block = ext4_blocks_count(EXT4_SB(inode->i_sb)->s_es) - 1;
+ /*
+ * If we are doing delayed allocation, we don't need take
+ * colour into account.
+ */
+ if (test_opt(inode->i_sb, DELALLOC))
+ return bg_start;
+
if (bg_start + EXT4_BLOCKS_PER_GROUP(inode->i_sb) <= last_block)
colour = (current->pid % 16) *
(EXT4_BLOCKS_PER_GROUP(inode->i_sb) / 16);
*
* Normally this function find the preferred place for block allocation,
* returns it.
+ * Because this is only used for non-extent files, we limit the block nr
+ * to 32 bits.
*/
static ext4_fsblk_t ext4_find_goal(struct inode *inode, ext4_lblk_t block,
- Indirect *partial)
+ Indirect *partial)
{
- struct ext4_block_alloc_info *block_i;
-
- block_i = EXT4_I(inode)->i_block_alloc_info;
+ ext4_fsblk_t goal;
/*
- * try the heuristic for sequential allocation,
- * failing that at least try to get decent locality.
+ * XXX need to get goal block from mballoc's data structures
*/
- if (block_i && (block == block_i->last_alloc_logical_block + 1)
- && (block_i->last_alloc_physical_block != 0)) {
- return block_i->last_alloc_physical_block + 1;
- }
- return ext4_find_near(inode, partial);
+ goal = ext4_find_near(inode, partial);
+ goal = goal & EXT4_MAX_BLOCK_FILE_PHYS;
+ return goal;
}
/**
* return the total number of blocks to be allocate, including the
* direct and indirect blocks.
*/
-static int ext4_blks_to_allocate(Indirect *branch, int k, unsigned long blks,
- int blocks_to_boundary)
+static int ext4_blks_to_allocate(Indirect *branch, int k, unsigned int blks,
+ int blocks_to_boundary)
{
- unsigned long count = 0;
+ unsigned int count = 0;
/*
* Simple case, [t,d]Indirect block(s) has not allocated yet
* direct blocks
*/
static int ext4_alloc_blocks(handle_t *handle, struct inode *inode,
- ext4_fsblk_t goal, int indirect_blks, int blks,
- ext4_fsblk_t new_blocks[4], int *err)
+ ext4_lblk_t iblock, ext4_fsblk_t goal,
+ int indirect_blks, int blks,
+ ext4_fsblk_t new_blocks[4], int *err)
{
+ struct ext4_allocation_request ar;
int target, i;
- unsigned long count = 0;
+ unsigned long count = 0, blk_allocated = 0;
int index = 0;
ext4_fsblk_t current_block = 0;
int ret = 0;
* the first direct block of this branch. That's the
* minimum number of blocks need to allocate(required)
*/
- target = blks + indirect_blks;
-
- while (1) {
+ /* first we try to allocate the indirect blocks */
+ target = indirect_blks;
+ while (target > 0) {
count = target;
/* allocating blocks for indirect blocks and direct blocks */
- current_block = ext4_new_blocks(handle,inode,goal,&count,err);
+ current_block = ext4_new_meta_blocks(handle, inode,
+ goal, &count, err);
if (*err)
goto failed_out;
+ BUG_ON(current_block + count > EXT4_MAX_BLOCK_FILE_PHYS);
+
target -= count;
/* allocate blocks for indirect blocks */
while (index < indirect_blks && count) {
new_blocks[index++] = current_block++;
count--;
}
-
- if (count > 0)
+ if (count > 0) {
+ /*
+ * save the new block number
+ * for the first direct block
+ */
+ new_blocks[index] = current_block;
+ printk(KERN_INFO "%s returned more blocks than "
+ "requested\n", __func__);
+ WARN_ON(1);
break;
+ }
}
- /* save the new block number for the first direct block */
- new_blocks[index] = current_block;
-
+ target = blks - count ;
+ blk_allocated = count;
+ if (!target)
+ goto allocated;
+ /* Now allocate data blocks */
+ memset(&ar, 0, sizeof(ar));
+ ar.inode = inode;
+ ar.goal = goal;
+ ar.len = target;
+ ar.logical = iblock;
+ if (S_ISREG(inode->i_mode))
+ /* enable in-core preallocation only for regular files */
+ ar.flags = EXT4_MB_HINT_DATA;
+
+ current_block = ext4_mb_new_blocks(handle, &ar, err);
+ BUG_ON(current_block + ar.len > EXT4_MAX_BLOCK_FILE_PHYS);
+
+ if (*err && (target == blks)) {
+ /*
+ * if the allocation failed and we didn't allocate
+ * any blocks before
+ */
+ goto failed_out;
+ }
+ if (!*err) {
+ if (target == blks) {
+ /*
+ * save the new block number
+ * for the first direct block
+ */
+ new_blocks[index] = current_block;
+ }
+ blk_allocated += ar.len;
+ }
+allocated:
/* total number of blocks allocated for direct blocks */
- ret = count;
+ ret = blk_allocated;
*err = 0;
return ret;
failed_out:
- for (i = 0; i <index; i++)
+ for (i = 0; i < index; i++)
ext4_free_blocks(handle, inode, new_blocks[i], 1, 0);
return ret;
}
* as described above and return 0.
*/
static int ext4_alloc_branch(handle_t *handle, struct inode *inode,
- int indirect_blks, int *blks, ext4_fsblk_t goal,
- ext4_lblk_t *offsets, Indirect *branch)
+ ext4_lblk_t iblock, int indirect_blks,
+ int *blks, ext4_fsblk_t goal,
+ ext4_lblk_t *offsets, Indirect *branch)
{
int blocksize = inode->i_sb->s_blocksize;
int i, n = 0;
ext4_fsblk_t new_blocks[4];
ext4_fsblk_t current_block;
- num = ext4_alloc_blocks(handle, inode, goal, indirect_blks,
+ num = ext4_alloc_blocks(handle, inode, iblock, goal, indirect_blks,
*blks, new_blocks, &err);
if (err)
return err;
BUFFER_TRACE(bh, "call get_create_access");
err = ext4_journal_get_create_access(handle, bh);
if (err) {
+ /* Don't brelse(bh) here; it's done in
+ * ext4_journal_forget() below */
unlock_buffer(bh);
- brelse(bh);
goto failed;
}
branch[n].p = (__le32 *) bh->b_data + offsets[n];
branch[n].key = cpu_to_le32(new_blocks[n]);
*branch[n].p = branch[n].key;
- if ( n == indirect_blks) {
+ if (n == indirect_blks) {
current_block = new_blocks[n];
/*
* End of chain, update the last new metablock of
* the chain to point to the new allocated
* data blocks numbers
*/
- for (i=1; i < num; i++)
+ for (i = 1; i < num; i++)
*(branch[n].p + i) = cpu_to_le32(++current_block);
}
BUFFER_TRACE(bh, "marking uptodate");
set_buffer_uptodate(bh);
unlock_buffer(bh);
- BUFFER_TRACE(bh, "call ext4_journal_dirty_metadata");
- err = ext4_journal_dirty_metadata(handle, bh);
+ BUFFER_TRACE(bh, "call ext4_handle_dirty_metadata");
+ err = ext4_handle_dirty_metadata(handle, inode, bh);
if (err)
goto failed;
}
BUFFER_TRACE(branch[i].bh, "call jbd2_journal_forget");
ext4_journal_forget(handle, branch[i].bh);
}
- for (i = 0; i <indirect_blks; i++)
+ for (i = 0; i < indirect_blks; i++)
ext4_free_blocks(handle, inode, new_blocks[i], 1, 0);
ext4_free_blocks(handle, inode, new_blocks[i], num, 0);
* chain to new block and return 0.
*/
static int ext4_splice_branch(handle_t *handle, struct inode *inode,
- ext4_lblk_t block, Indirect *where, int num, int blks)
+ ext4_lblk_t block, Indirect *where, int num,
+ int blks)
{
int i;
int err = 0;
- struct ext4_block_alloc_info *block_i;
ext4_fsblk_t current_block;
- block_i = EXT4_I(inode)->i_block_alloc_info;
/*
* If we're splicing into a [td]indirect block (as opposed to the
* inode) then we need to get write access to the [td]indirect block
if (num == 0 && blks > 1) {
current_block = le32_to_cpu(where->key) + 1;
for (i = 1; i < blks; i++)
- *(where->p + i ) = cpu_to_le32(current_block++);
- }
-
- /*
- * update the most recently allocated logical & physical block
- * in i_block_alloc_info, to assist find the proper goal block for next
- * allocation
- */
- if (block_i) {
- block_i->last_alloc_logical_block = block + blks - 1;
- block_i->last_alloc_physical_block =
- le32_to_cpu(where[num].key) + blks - 1;
+ *(where->p + i) = cpu_to_le32(current_block++);
}
/* We are done with atomic stuff, now do the rest of housekeeping */
-
- inode->i_ctime = ext4_current_time(inode);
- ext4_mark_inode_dirty(handle, inode);
-
/* had we spliced it onto indirect block? */
if (where->bh) {
/*
* generic_commit_write->__mark_inode_dirty->ext4_dirty_inode.
*/
jbd_debug(5, "splicing indirect only\n");
- BUFFER_TRACE(where->bh, "call ext4_journal_dirty_metadata");
- err = ext4_journal_dirty_metadata(handle, where->bh);
+ BUFFER_TRACE(where->bh, "call ext4_handle_dirty_metadata");
+ err = ext4_handle_dirty_metadata(handle, inode, where->bh);
if (err)
goto err_out;
} else {
/*
* OK, we spliced it into the inode itself on a direct block.
- * Inode was dirtied above.
*/
+ ext4_mark_inode_dirty(handle, inode);
jbd_debug(5, "splicing direct\n");
}
return err;
}
/*
+ * The ext4_ind_get_blocks() function handles non-extents inodes
+ * (i.e., using the traditional indirect/double-indirect i_blocks
+ * scheme) for ext4_get_blocks().
+ *
* Allocation strategy is simple: if we have to allocate something, we will
* have to go the whole way to leaf. So let's do it before attaching anything
* to tree, set linkage between the newborn blocks, write them if sync is
* return = 0, if plain lookup failed.
* return < 0, error case.
*
- *
- * Need to be called with
- * down_read(&EXT4_I(inode)->i_data_sem) if not allocating file system block
- * (ie, create is zero). Otherwise down_write(&EXT4_I(inode)->i_data_sem)
+ * The ext4_ind_get_blocks() function should be called with
+ * down_write(&EXT4_I(inode)->i_data_sem) if allocating filesystem
+ * blocks (i.e., flags has EXT4_GET_BLOCKS_CREATE set) or
+ * down_read(&EXT4_I(inode)->i_data_sem) if not allocating file system
+ * blocks.
*/
-int ext4_get_blocks_handle(handle_t *handle, struct inode *inode,
- ext4_lblk_t iblock, unsigned long maxblocks,
- struct buffer_head *bh_result,
- int create, int extend_disksize)
+static int ext4_ind_get_blocks(handle_t *handle, struct inode *inode,
+ ext4_lblk_t iblock, unsigned int maxblocks,
+ struct buffer_head *bh_result,
+ int flags)
{
int err = -EIO;
ext4_lblk_t offsets[4];
int indirect_blks;
int blocks_to_boundary = 0;
int depth;
- struct ext4_inode_info *ei = EXT4_I(inode);
int count = 0;
ext4_fsblk_t first_block = 0;
-
J_ASSERT(!(EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL));
- J_ASSERT(handle != NULL || create == 0);
+ J_ASSERT(handle != NULL || (flags & EXT4_GET_BLOCKS_CREATE) == 0);
depth = ext4_block_to_path(inode, iblock, offsets,
- &blocks_to_boundary);
+ &blocks_to_boundary);
if (depth == 0)
goto out;
}
/* Next simple case - plain lookup or failed read of indirect block */
- if (!create || err == -EIO)
+ if ((flags & EXT4_GET_BLOCKS_CREATE) == 0 || err == -EIO)
goto cleanup;
/*
- * Okay, we need to do block allocation. Lazily initialize the block
- * allocation info here if necessary
+ * Okay, we need to do block allocation.
*/
- if (S_ISREG(inode->i_mode) && (!ei->i_block_alloc_info))
- ext4_init_block_alloc_info(inode);
-
goal = ext4_find_goal(inode, iblock, partial);
/* the number of blocks need to allocate for [d,t]indirect blocks */
/*
* Block out ext4_truncate while we alter the tree
*/
- err = ext4_alloc_branch(handle, inode, indirect_blks, &count, goal,
+ err = ext4_alloc_branch(handle, inode, iblock, indirect_blks,
+ &count, goal,
offsets + (partial - chain), partial);
/*
*/
if (!err)
err = ext4_splice_branch(handle, inode, iblock,
- partial, indirect_blks, count);
- /*
- * i_disksize growing is protected by i_data_sem. Don't forget to
- * protect it if you're about to implement concurrent
- * ext4_get_block() -bzzz
- */
- if (!err && extend_disksize && inode->i_size > ei->i_disksize)
- ei->i_disksize = inode->i_size;
- if (err)
+ partial, indirect_blks, count);
+ else
goto cleanup;
set_buffer_new(bh_result);
return err;
}
-/* Maximum number of blocks we map for direct IO at once. */
-#define DIO_MAX_BLOCKS 4096
+qsize_t ext4_get_reserved_space(struct inode *inode)
+{
+ unsigned long long total;
+
+ spin_lock(&EXT4_I(inode)->i_block_reservation_lock);
+ total = EXT4_I(inode)->i_reserved_data_blocks +
+ EXT4_I(inode)->i_reserved_meta_blocks;
+ spin_unlock(&EXT4_I(inode)->i_block_reservation_lock);
+
+ return total;
+}
/*
- * Number of credits we need for writing DIO_MAX_BLOCKS:
- * We need sb + group descriptor + bitmap + inode -> 4
- * For B blocks with A block pointers per block we need:
- * 1 (triple ind.) + (B/A/A + 2) (doubly ind.) + (B/A + 2) (indirect).
- * If we plug in 4096 for B and 256 for A (for 1KB block size), we get 25.
+ * Calculate the number of metadata blocks need to reserve
+ * to allocate @blocks for non extent file based file
*/
-#define DIO_CREDITS 25
+static int ext4_indirect_calc_metadata_amount(struct inode *inode, int blocks)
+{
+ int icap = EXT4_ADDR_PER_BLOCK(inode->i_sb);
+ int ind_blks, dind_blks, tind_blks;
+
+ /* number of new indirect blocks needed */
+ ind_blks = (blocks + icap - 1) / icap;
+ dind_blks = (ind_blks + icap - 1) / icap;
+
+ tind_blks = 1;
+
+ return ind_blks + dind_blks + tind_blks;
+}
/*
+ * Calculate the number of metadata blocks need to reserve
+ * to allocate given number of blocks
+ */
+static int ext4_calc_metadata_amount(struct inode *inode, int blocks)
+{
+ if (!blocks)
+ return 0;
+
+ if (EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL)
+ return ext4_ext_calc_metadata_amount(inode, blocks);
+
+ return ext4_indirect_calc_metadata_amount(inode, blocks);
+}
+
+static void ext4_da_update_reserve_space(struct inode *inode, int used)
+{
+ struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
+ int total, mdb, mdb_free;
+
+ spin_lock(&EXT4_I(inode)->i_block_reservation_lock);
+ /* recalculate the number of metablocks still need to be reserved */
+ total = EXT4_I(inode)->i_reserved_data_blocks - used;
+ mdb = ext4_calc_metadata_amount(inode, total);
+
+ /* figure out how many metablocks to release */
+ BUG_ON(mdb > EXT4_I(inode)->i_reserved_meta_blocks);
+ mdb_free = EXT4_I(inode)->i_reserved_meta_blocks - mdb;
+
+ if (mdb_free) {
+ /* Account for allocated meta_blocks */
+ mdb_free -= EXT4_I(inode)->i_allocated_meta_blocks;
+
+ /* update fs dirty blocks counter */
+ percpu_counter_sub(&sbi->s_dirtyblocks_counter, mdb_free);
+ EXT4_I(inode)->i_allocated_meta_blocks = 0;
+ EXT4_I(inode)->i_reserved_meta_blocks = mdb;
+ }
+
+ /* update per-inode reservations */
+ BUG_ON(used > EXT4_I(inode)->i_reserved_data_blocks);
+ EXT4_I(inode)->i_reserved_data_blocks -= used;
+ spin_unlock(&EXT4_I(inode)->i_block_reservation_lock);
+
+ /*
+ * free those over-booking quota for metadata blocks
+ */
+ if (mdb_free)
+ vfs_dq_release_reservation_block(inode, mdb_free);
+
+ /*
+ * If we have done all the pending block allocations and if
+ * there aren't any writers on the inode, we can discard the
+ * inode's preallocations.
+ */
+ if (!total && (atomic_read(&inode->i_writecount) == 0))
+ ext4_discard_preallocations(inode);
+}
+
+static int check_block_validity(struct inode *inode, const char *msg,
+ sector_t logical, sector_t phys, int len)
+{
+ if (!ext4_data_block_valid(EXT4_SB(inode->i_sb), phys, len)) {
+ ext4_error(inode->i_sb, msg,
+ "inode #%lu logical block %llu mapped to %llu "
+ "(size %d)", inode->i_ino,
+ (unsigned long long) logical,
+ (unsigned long long) phys, len);
+ return -EIO;
+ }
+ return 0;
+}
+
+/*
+ * Return the number of contiguous dirty pages in a given inode
+ * starting at page frame idx.
+ */
+static pgoff_t ext4_num_dirty_pages(struct inode *inode, pgoff_t idx,
+ unsigned int max_pages)
+{
+ struct address_space *mapping = inode->i_mapping;
+ pgoff_t index;
+ struct pagevec pvec;
+ pgoff_t num = 0;
+ int i, nr_pages, done = 0;
+
+ if (max_pages == 0)
+ return 0;
+ pagevec_init(&pvec, 0);
+ while (!done) {
+ index = idx;
+ nr_pages = pagevec_lookup_tag(&pvec, mapping, &index,
+ PAGECACHE_TAG_DIRTY,
+ (pgoff_t)PAGEVEC_SIZE);
+ if (nr_pages == 0)
+ break;
+ for (i = 0; i < nr_pages; i++) {
+ struct page *page = pvec.pages[i];
+ struct buffer_head *bh, *head;
+
+ lock_page(page);
+ if (unlikely(page->mapping != mapping) ||
+ !PageDirty(page) ||
+ PageWriteback(page) ||
+ page->index != idx) {
+ done = 1;
+ unlock_page(page);
+ break;
+ }
+ if (page_has_buffers(page)) {
+ bh = head = page_buffers(page);
+ do {
+ if (!buffer_delay(bh) &&
+ !buffer_unwritten(bh))
+ done = 1;
+ bh = bh->b_this_page;
+ } while (!done && (bh != head));
+ }
+ unlock_page(page);
+ if (done)
+ break;
+ idx++;
+ num++;
+ if (num >= max_pages)
+ break;
+ }
+ pagevec_release(&pvec);
+ }
+ return num;
+}
+
+/*
+ * The ext4_get_blocks() function tries to look up the requested blocks,
+ * and returns if the blocks are already mapped.
*
- *
- * ext4_ext4 get_block() wrapper function
- * It will do a look up first, and returns if the blocks already mapped.
* Otherwise it takes the write lock of the i_data_sem and allocate blocks
* and store the allocated blocks in the result buffer head and mark it
* mapped.
*
* If file type is extents based, it will call ext4_ext_get_blocks(),
- * Otherwise, call with ext4_get_blocks_handle() to handle indirect mapping
+ * Otherwise, call with ext4_ind_get_blocks() to handle indirect mapping
* based files
*
* On success, it returns the number of blocks being mapped or allocate.
*
* It returns the error in case of allocation failure.
*/
-int ext4_get_blocks_wrap(handle_t *handle, struct inode *inode, sector_t block,
- unsigned long max_blocks, struct buffer_head *bh,
- int create, int extend_disksize)
+int ext4_get_blocks(handle_t *handle, struct inode *inode, sector_t block,
+ unsigned int max_blocks, struct buffer_head *bh,
+ int flags)
{
int retval;
clear_buffer_mapped(bh);
+ clear_buffer_unwritten(bh);
+ ext_debug("ext4_get_blocks(): inode %lu, flag %d, max_blocks %u,"
+ "logical block %lu\n", inode->i_ino, flags, max_blocks,
+ (unsigned long)block);
/*
- * Try to see if we can get the block without requesting
- * for new file system block.
+ * Try to see if we can get the block without requesting a new
+ * file system block.
*/
down_read((&EXT4_I(inode)->i_data_sem));
if (EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL) {
retval = ext4_ext_get_blocks(handle, inode, block, max_blocks,
- bh, 0, 0);
+ bh, 0);
} else {
- retval = ext4_get_blocks_handle(handle,
- inode, block, max_blocks, bh, 0, 0);
+ retval = ext4_ind_get_blocks(handle, inode, block, max_blocks,
+ bh, 0);
}
up_read((&EXT4_I(inode)->i_data_sem));
+ if (retval > 0 && buffer_mapped(bh)) {
+ int ret = check_block_validity(inode, "file system corruption",
+ block, bh->b_blocknr, retval);
+ if (ret != 0)
+ return ret;
+ }
+
/* If it is only a block(s) look up */
- if (!create)
+ if ((flags & EXT4_GET_BLOCKS_CREATE) == 0)
return retval;
/*
return retval;
/*
+ * When we call get_blocks without the create flag, the
+ * BH_Unwritten flag could have gotten set if the blocks
+ * requested were part of a uninitialized extent. We need to
+ * clear this flag now that we are committed to convert all or
+ * part of the uninitialized extent to be an initialized
+ * extent. This is because we need to avoid the combination
+ * of BH_Unwritten and BH_Mapped flags being simultaneously
+ * set on the buffer_head.
+ */
+ clear_buffer_unwritten(bh);
+
+ /*
* New blocks allocate and/or writing to uninitialized extent
* will possibly result in updating i_data, so we take
* the write lock of i_data_sem, and call get_blocks()
* with create == 1 flag.
*/
down_write((&EXT4_I(inode)->i_data_sem));
+
+ /*
+ * if the caller is from delayed allocation writeout path
+ * we have already reserved fs blocks for allocation
+ * let the underlying get_block() function know to
+ * avoid double accounting
+ */
+ if (flags & EXT4_GET_BLOCKS_DELALLOC_RESERVE)
+ EXT4_I(inode)->i_delalloc_reserved_flag = 1;
/*
* We need to check for EXT4 here because migrate
* could have changed the inode type in between
*/
if (EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL) {
retval = ext4_ext_get_blocks(handle, inode, block, max_blocks,
- bh, create, extend_disksize);
+ bh, flags);
} else {
- retval = ext4_get_blocks_handle(handle, inode, block,
- max_blocks, bh, create, extend_disksize);
+ retval = ext4_ind_get_blocks(handle, inode, block,
+ max_blocks, bh, flags);
if (retval > 0 && buffer_new(bh)) {
/*
* i_data's format changing. Force the migrate
* to fail by clearing migrate flags
*/
- EXT4_I(inode)->i_flags = EXT4_I(inode)->i_flags &
- ~EXT4_EXT_MIGRATE;
+ EXT4_I(inode)->i_state &= ~EXT4_STATE_EXT_MIGRATE;
}
}
+
+ if (flags & EXT4_GET_BLOCKS_DELALLOC_RESERVE)
+ EXT4_I(inode)->i_delalloc_reserved_flag = 0;
+
+ /*
+ * Update reserved blocks/metadata blocks after successful
+ * block allocation which had been deferred till now.
+ */
+ if ((retval > 0) && (flags & EXT4_GET_BLOCKS_UPDATE_RESERVE_SPACE))
+ ext4_da_update_reserve_space(inode, retval);
+
up_write((&EXT4_I(inode)->i_data_sem));
+ if (retval > 0 && buffer_mapped(bh)) {
+ int ret = check_block_validity(inode, "file system "
+ "corruption after allocation",
+ block, bh->b_blocknr, retval);
+ if (ret != 0)
+ return ret;
+ }
return retval;
}
-static int ext4_get_block(struct inode *inode, sector_t iblock,
- struct buffer_head *bh_result, int create)
+/* Maximum number of blocks we map for direct IO at once. */
+#define DIO_MAX_BLOCKS 4096
+
+int ext4_get_block(struct inode *inode, sector_t iblock,
+ struct buffer_head *bh_result, int create)
{
handle_t *handle = ext4_journal_current_handle();
int ret = 0, started = 0;
unsigned max_blocks = bh_result->b_size >> inode->i_blkbits;
+ int dio_credits;
if (create && !handle) {
/* Direct IO write... */
if (max_blocks > DIO_MAX_BLOCKS)
max_blocks = DIO_MAX_BLOCKS;
- handle = ext4_journal_start(inode, DIO_CREDITS +
- 2 * EXT4_QUOTA_TRANS_BLOCKS(inode->i_sb));
+ dio_credits = ext4_chunk_trans_blocks(inode, max_blocks);
+ handle = ext4_journal_start(inode, dio_credits);
if (IS_ERR(handle)) {
ret = PTR_ERR(handle);
goto out;
started = 1;
}
- ret = ext4_get_blocks_wrap(handle, inode, iblock,
- max_blocks, bh_result, create, 0);
+ ret = ext4_get_blocks(handle, inode, iblock, max_blocks, bh_result,
+ create ? EXT4_GET_BLOCKS_CREATE : 0);
if (ret > 0) {
bh_result->b_size = (ret << inode->i_blkbits);
ret = 0;
{
struct buffer_head dummy;
int fatal = 0, err;
+ int flags = 0;
J_ASSERT(handle != NULL || create == 0);
dummy.b_state = 0;
dummy.b_blocknr = -1000;
buffer_trace_init(&dummy.b_history);
- err = ext4_get_blocks_wrap(handle, inode, block, 1,
- &dummy, create, 1);
+ if (create)
+ flags |= EXT4_GET_BLOCKS_CREATE;
+ err = ext4_get_blocks(handle, inode, block, 1, &dummy, flags);
/*
- * ext4_get_blocks_handle() returns number of blocks
- * mapped. 0 in case of a HOLE.
+ * ext4_get_blocks() returns number of blocks mapped. 0 in
+ * case of a HOLE.
*/
if (err > 0) {
if (err > 1)
BUFFER_TRACE(bh, "call get_create_access");
fatal = ext4_journal_get_create_access(handle, bh);
if (!fatal && !buffer_uptodate(bh)) {
- memset(bh->b_data,0,inode->i_sb->s_blocksize);
+ memset(bh->b_data, 0, inode->i_sb->s_blocksize);
set_buffer_uptodate(bh);
}
unlock_buffer(bh);
- BUFFER_TRACE(bh, "call ext4_journal_dirty_metadata");
- err = ext4_journal_dirty_metadata(handle, bh);
+ BUFFER_TRACE(bh, "call ext4_handle_dirty_metadata");
+ err = ext4_handle_dirty_metadata(handle, inode, bh);
if (!fatal)
fatal = err;
} else {
struct buffer_head *ext4_bread(handle_t *handle, struct inode *inode,
ext4_lblk_t block, int create, int *err)
{
- struct buffer_head * bh;
+ struct buffer_head *bh;
bh = ext4_getblk(handle, inode, block, create, err);
if (!bh)
return NULL;
}
-static int walk_page_buffers( handle_t *handle,
- struct buffer_head *head,
- unsigned from,
- unsigned to,
- int *partial,
- int (*fn)( handle_t *handle,
- struct buffer_head *bh))
+static int walk_page_buffers(handle_t *handle,
+ struct buffer_head *head,
+ unsigned from,
+ unsigned to,
+ int *partial,
+ int (*fn)(handle_t *handle,
+ struct buffer_head *bh))
{
struct buffer_head *bh;
unsigned block_start, block_end;
int err, ret = 0;
struct buffer_head *next;
- for ( bh = head, block_start = 0;
- ret == 0 && (bh != head || !block_start);
- block_start = block_end, bh = next)
- {
+ for (bh = head, block_start = 0;
+ ret == 0 && (bh != head || !block_start);
+ block_start = block_end, bh = next) {
next = bh->b_this_page;
block_end = block_start + blocksize;
if (block_end <= from || block_start >= to) {
* write.
*/
static int do_journal_get_write_access(handle_t *handle,
- struct buffer_head *bh)
+ struct buffer_head *bh)
{
if (!buffer_mapped(bh) || buffer_freed(bh))
return 0;
}
static int ext4_write_begin(struct file *file, struct address_space *mapping,
- loff_t pos, unsigned len, unsigned flags,
- struct page **pagep, void **fsdata)
+ loff_t pos, unsigned len, unsigned flags,
+ struct page **pagep, void **fsdata)
{
- struct inode *inode = mapping->host;
- int ret, needed_blocks = ext4_writepage_trans_blocks(inode);
+ struct inode *inode = mapping->host;
+ int ret, needed_blocks;
handle_t *handle;
int retries = 0;
- struct page *page;
- pgoff_t index;
- unsigned from, to;
+ struct page *page;
+ pgoff_t index;
+ unsigned from, to;
- index = pos >> PAGE_CACHE_SHIFT;
- from = pos & (PAGE_CACHE_SIZE - 1);
- to = from + len;
+ trace_ext4_write_begin(inode, pos, len, flags);
+ /*
+ * Reserve one block more for addition to orphan list in case
+ * we allocate blocks but write fails for some reason
+ */
+ needed_blocks = ext4_writepage_trans_blocks(inode) + 1;
+ index = pos >> PAGE_CACHE_SHIFT;
+ from = pos & (PAGE_CACHE_SIZE - 1);
+ to = from + len;
retry:
- page = __grab_cache_page(mapping, index);
- if (!page)
- return -ENOMEM;
- *pagep = page;
+ handle = ext4_journal_start(inode, needed_blocks);
+ if (IS_ERR(handle)) {
+ ret = PTR_ERR(handle);
+ goto out;
+ }
+
+ /* We cannot recurse into the filesystem as the transaction is already
+ * started */
+ flags |= AOP_FLAG_NOFS;
- handle = ext4_journal_start(inode, needed_blocks);
- if (IS_ERR(handle)) {
- unlock_page(page);
- page_cache_release(page);
- ret = PTR_ERR(handle);
- goto out;
+ page = grab_cache_page_write_begin(mapping, index, flags);
+ if (!page) {
+ ext4_journal_stop(handle);
+ ret = -ENOMEM;
+ goto out;
}
+ *pagep = page;
ret = block_write_begin(file, mapping, pos, len, flags, pagep, fsdata,
- ext4_get_block);
+ ext4_get_block);
if (!ret && ext4_should_journal_data(inode)) {
ret = walk_page_buffers(handle, page_buffers(page),
}
if (ret) {
+ unlock_page(page);
+ page_cache_release(page);
+ /*
+ * block_write_begin may have instantiated a few blocks
+ * outside i_size. Trim these off again. Don't need
+ * i_size_read because we hold i_mutex.
+ *
+ * Add inode to orphan list in case we crash before
+ * truncate finishes
+ */
+ if (pos + len > inode->i_size && ext4_can_truncate(inode))
+ ext4_orphan_add(handle, inode);
+
ext4_journal_stop(handle);
- unlock_page(page);
- page_cache_release(page);
+ if (pos + len > inode->i_size) {
+ ext4_truncate(inode);
+ /*
+ * If truncate failed early the inode might
+ * still be on the orphan list; we need to
+ * make sure the inode is removed from the
+ * orphan list in that case.
+ */
+ if (inode->i_nlink)
+ ext4_orphan_del(NULL, inode);
+ }
}
if (ret == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries))
return ret;
}
-int ext4_journal_dirty_data(handle_t *handle, struct buffer_head *bh)
-{
- int err = jbd2_journal_dirty_data(handle, bh);
- if (err)
- ext4_journal_abort_handle(__FUNCTION__, __FUNCTION__,
- bh, handle, err);
- return err;
-}
-
/* For write_end() in data=journal mode */
static int write_end_fn(handle_t *handle, struct buffer_head *bh)
{
if (!buffer_mapped(bh) || buffer_freed(bh))
return 0;
set_buffer_uptodate(bh);
- return ext4_journal_dirty_metadata(handle, bh);
+ return ext4_handle_dirty_metadata(handle, NULL, bh);
}
-/*
- * Generic write_end handler for ordered and writeback ext4 journal modes.
- * We can't use generic_write_end, because that unlocks the page and we need to
- * unlock the page after ext4_journal_stop, but ext4_journal_stop must run
- * after block_write_end.
- */
static int ext4_generic_write_end(struct file *file,
- struct address_space *mapping,
- loff_t pos, unsigned len, unsigned copied,
- struct page *page, void *fsdata)
+ struct address_space *mapping,
+ loff_t pos, unsigned len, unsigned copied,
+ struct page *page, void *fsdata)
{
- struct inode *inode = file->f_mapping->host;
+ int i_size_changed = 0;
+ struct inode *inode = mapping->host;
+ handle_t *handle = ext4_journal_current_handle();
copied = block_write_end(file, mapping, pos, len, copied, page, fsdata);
- if (pos+copied > inode->i_size) {
- i_size_write(inode, pos+copied);
- mark_inode_dirty(inode);
+ /*
+ * No need to use i_size_read() here, the i_size
+ * cannot change under us because we hold i_mutex.
+ *
+ * But it's important to update i_size while still holding page lock:
+ * page writeout could otherwise come in and zero beyond i_size.
+ */
+ if (pos + copied > inode->i_size) {
+ i_size_write(inode, pos + copied);
+ i_size_changed = 1;
+ }
+
+ if (pos + copied > EXT4_I(inode)->i_disksize) {
+ /* We need to mark inode dirty even if
+ * new_i_size is less that inode->i_size
+ * bu greater than i_disksize.(hint delalloc)
+ */
+ ext4_update_i_disksize(inode, (pos + copied));
+ i_size_changed = 1;
}
+ unlock_page(page);
+ page_cache_release(page);
+
+ /*
+ * Don't mark the inode dirty under page lock. First, it unnecessarily
+ * makes the holding time of page lock longer. Second, it forces lock
+ * ordering of page lock and transaction start for journaling
+ * filesystems.
+ */
+ if (i_size_changed)
+ ext4_mark_inode_dirty(handle, inode);
return copied;
}
* buffers are managed internally.
*/
static int ext4_ordered_write_end(struct file *file,
- struct address_space *mapping,
- loff_t pos, unsigned len, unsigned copied,
- struct page *page, void *fsdata)
+ struct address_space *mapping,
+ loff_t pos, unsigned len, unsigned copied,
+ struct page *page, void *fsdata)
{
handle_t *handle = ext4_journal_current_handle();
- struct inode *inode = file->f_mapping->host;
- unsigned from, to;
+ struct inode *inode = mapping->host;
int ret = 0, ret2;
- from = pos & (PAGE_CACHE_SIZE - 1);
- to = from + len;
-
- ret = walk_page_buffers(handle, page_buffers(page),
- from, to, NULL, ext4_journal_dirty_data);
+ trace_ext4_ordered_write_end(inode, pos, len, copied);
+ ret = ext4_jbd2_file_inode(handle, inode);
if (ret == 0) {
- /*
- * generic_write_end() will run mark_inode_dirty() if i_size
- * changes. So let's piggyback the i_disksize mark_inode_dirty
- * into that.
- */
- loff_t new_i_size;
-
- new_i_size = pos + copied;
- if (new_i_size > EXT4_I(inode)->i_disksize)
- EXT4_I(inode)->i_disksize = new_i_size;
- copied = ext4_generic_write_end(file, mapping, pos, len, copied,
+ ret2 = ext4_generic_write_end(file, mapping, pos, len, copied,
page, fsdata);
- if (copied < 0)
- ret = copied;
+ copied = ret2;
+ if (pos + len > inode->i_size && ext4_can_truncate(inode))
+ /* if we have allocated more blocks and copied
+ * less. We will have blocks allocated outside
+ * inode->i_size. So truncate them
+ */
+ ext4_orphan_add(handle, inode);
+ if (ret2 < 0)
+ ret = ret2;
}
ret2 = ext4_journal_stop(handle);
if (!ret)
ret = ret2;
- unlock_page(page);
- page_cache_release(page);
+
+ if (pos + len > inode->i_size) {
+ ext4_truncate(inode);
+ /*
+ * If truncate failed early the inode might still be
+ * on the orphan list; we need to make sure the inode
+ * is removed from the orphan list in that case.
+ */
+ if (inode->i_nlink)
+ ext4_orphan_del(NULL, inode);
+ }
+
return ret ? ret : copied;
}
static int ext4_writeback_write_end(struct file *file,
- struct address_space *mapping,
- loff_t pos, unsigned len, unsigned copied,
- struct page *page, void *fsdata)
+ struct address_space *mapping,
+ loff_t pos, unsigned len, unsigned copied,
+ struct page *page, void *fsdata)
{
handle_t *handle = ext4_journal_current_handle();
- struct inode *inode = file->f_mapping->host;
+ struct inode *inode = mapping->host;
int ret = 0, ret2;
- loff_t new_i_size;
-
- new_i_size = pos + copied;
- if (new_i_size > EXT4_I(inode)->i_disksize)
- EXT4_I(inode)->i_disksize = new_i_size;
- copied = ext4_generic_write_end(file, mapping, pos, len, copied,
+ trace_ext4_writeback_write_end(inode, pos, len, copied);
+ ret2 = ext4_generic_write_end(file, mapping, pos, len, copied,
page, fsdata);
- if (copied < 0)
- ret = copied;
+ copied = ret2;
+ if (pos + len > inode->i_size && ext4_can_truncate(inode))
+ /* if we have allocated more blocks and copied
+ * less. We will have blocks allocated outside
+ * inode->i_size. So truncate them
+ */
+ ext4_orphan_add(handle, inode);
+
+ if (ret2 < 0)
+ ret = ret2;
ret2 = ext4_journal_stop(handle);
if (!ret)
ret = ret2;
- unlock_page(page);
- page_cache_release(page);
+
+ if (pos + len > inode->i_size) {
+ ext4_truncate(inode);
+ /*
+ * If truncate failed early the inode might still be
+ * on the orphan list; we need to make sure the inode
+ * is removed from the orphan list in that case.
+ */
+ if (inode->i_nlink)
+ ext4_orphan_del(NULL, inode);
+ }
return ret ? ret : copied;
}
static int ext4_journalled_write_end(struct file *file,
- struct address_space *mapping,
- loff_t pos, unsigned len, unsigned copied,
- struct page *page, void *fsdata)
+ struct address_space *mapping,
+ loff_t pos, unsigned len, unsigned copied,
+ struct page *page, void *fsdata)
{
handle_t *handle = ext4_journal_current_handle();
struct inode *inode = mapping->host;
int ret = 0, ret2;
int partial = 0;
unsigned from, to;
+ loff_t new_i_size;
+ trace_ext4_journalled_write_end(inode, pos, len, copied);
from = pos & (PAGE_CACHE_SIZE - 1);
to = from + len;
to, &partial, write_end_fn);
if (!partial)
SetPageUptodate(page);
- if (pos+copied > inode->i_size)
+ new_i_size = pos + copied;
+ if (new_i_size > inode->i_size)
i_size_write(inode, pos+copied);
EXT4_I(inode)->i_state |= EXT4_STATE_JDATA;
- if (inode->i_size > EXT4_I(inode)->i_disksize) {
- EXT4_I(inode)->i_disksize = inode->i_size;
+ if (new_i_size > EXT4_I(inode)->i_disksize) {
+ ext4_update_i_disksize(inode, new_i_size);
ret2 = ext4_mark_inode_dirty(handle, inode);
if (!ret)
ret = ret2;
}
+ unlock_page(page);
+ page_cache_release(page);
+ if (pos + len > inode->i_size && ext4_can_truncate(inode))
+ /* if we have allocated more blocks and copied
+ * less. We will have blocks allocated outside
+ * inode->i_size. So truncate them
+ */
+ ext4_orphan_add(handle, inode);
+
ret2 = ext4_journal_stop(handle);
if (!ret)
ret = ret2;
- unlock_page(page);
- page_cache_release(page);
+ if (pos + len > inode->i_size) {
+ ext4_truncate(inode);
+ /*
+ * If truncate failed early the inode might still be
+ * on the orphan list; we need to make sure the inode
+ * is removed from the orphan list in that case.
+ */
+ if (inode->i_nlink)
+ ext4_orphan_del(NULL, inode);
+ }
return ret ? ret : copied;
}
+static int ext4_da_reserve_space(struct inode *inode, int nrblocks)
+{
+ int retries = 0;
+ struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
+ unsigned long md_needed, mdblocks, total = 0;
+
+ /*
+ * recalculate the amount of metadata blocks to reserve
+ * in order to allocate nrblocks
+ * worse case is one extent per block
+ */
+repeat:
+ spin_lock(&EXT4_I(inode)->i_block_reservation_lock);
+ total = EXT4_I(inode)->i_reserved_data_blocks + nrblocks;
+ mdblocks = ext4_calc_metadata_amount(inode, total);
+ BUG_ON(mdblocks < EXT4_I(inode)->i_reserved_meta_blocks);
+
+ md_needed = mdblocks - EXT4_I(inode)->i_reserved_meta_blocks;
+ total = md_needed + nrblocks;
+
+ /*
+ * Make quota reservation here to prevent quota overflow
+ * later. Real quota accounting is done at pages writeout
+ * time.
+ */
+ if (vfs_dq_reserve_block(inode, total)) {
+ spin_unlock(&EXT4_I(inode)->i_block_reservation_lock);
+ return -EDQUOT;
+ }
+
+ if (ext4_claim_free_blocks(sbi, total)) {
+ spin_unlock(&EXT4_I(inode)->i_block_reservation_lock);
+ vfs_dq_release_reservation_block(inode, total);
+ if (ext4_should_retry_alloc(inode->i_sb, &retries)) {
+ yield();
+ goto repeat;
+ }
+ return -ENOSPC;
+ }
+ EXT4_I(inode)->i_reserved_data_blocks += nrblocks;
+ EXT4_I(inode)->i_reserved_meta_blocks = mdblocks;
+
+ spin_unlock(&EXT4_I(inode)->i_block_reservation_lock);
+ return 0; /* success */
+}
+
+static void ext4_da_release_space(struct inode *inode, int to_free)
+{
+ struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
+ int total, mdb, mdb_free, release;
+
+ if (!to_free)
+ return; /* Nothing to release, exit */
+
+ spin_lock(&EXT4_I(inode)->i_block_reservation_lock);
+
+ if (!EXT4_I(inode)->i_reserved_data_blocks) {
+ /*
+ * if there is no reserved blocks, but we try to free some
+ * then the counter is messed up somewhere.
+ * but since this function is called from invalidate
+ * page, it's harmless to return without any action
+ */
+ printk(KERN_INFO "ext4 delalloc try to release %d reserved "
+ "blocks for inode %lu, but there is no reserved "
+ "data blocks\n", to_free, inode->i_ino);
+ spin_unlock(&EXT4_I(inode)->i_block_reservation_lock);
+ return;
+ }
+
+ /* recalculate the number of metablocks still need to be reserved */
+ total = EXT4_I(inode)->i_reserved_data_blocks - to_free;
+ mdb = ext4_calc_metadata_amount(inode, total);
+
+ /* figure out how many metablocks to release */
+ BUG_ON(mdb > EXT4_I(inode)->i_reserved_meta_blocks);
+ mdb_free = EXT4_I(inode)->i_reserved_meta_blocks - mdb;
+
+ release = to_free + mdb_free;
+
+ /* update fs dirty blocks counter for truncate case */
+ percpu_counter_sub(&sbi->s_dirtyblocks_counter, release);
+
+ /* update per-inode reservations */
+ BUG_ON(to_free > EXT4_I(inode)->i_reserved_data_blocks);
+ EXT4_I(inode)->i_reserved_data_blocks -= to_free;
+
+ BUG_ON(mdb > EXT4_I(inode)->i_reserved_meta_blocks);
+ EXT4_I(inode)->i_reserved_meta_blocks = mdb;
+ spin_unlock(&EXT4_I(inode)->i_block_reservation_lock);
+
+ vfs_dq_release_reservation_block(inode, release);
+}
+
+static void ext4_da_page_release_reservation(struct page *page,
+ unsigned long offset)
+{
+ int to_release = 0;
+ struct buffer_head *head, *bh;
+ unsigned int curr_off = 0;
+
+ head = page_buffers(page);
+ bh = head;
+ do {
+ unsigned int next_off = curr_off + bh->b_size;
+
+ if ((offset <= curr_off) && (buffer_delay(bh))) {
+ to_release++;
+ clear_buffer_delay(bh);
+ }
+ curr_off = next_off;
+ } while ((bh = bh->b_this_page) != head);
+ ext4_da_release_space(page->mapping->host, to_release);
+}
+
/*
- * bmap() is special. It gets used by applications such as lilo and by
- * the swapper to find the on-disk block of a specific piece of data.
+ * Delayed allocation stuff
+ */
+
+/*
+ * mpage_da_submit_io - walks through extent of pages and try to write
+ * them with writepage() call back
*
- * Naturally, this is dangerous if the block concerned is still in the
- * journal. If somebody makes a swapfile on an ext4 data-journaling
- * filesystem and enables swap, then they may get a nasty shock when the
- * data getting swapped to that swapfile suddenly gets overwritten by
- * the original zero's written out previously to the journal and
- * awaiting writeback in the kernel's buffer cache.
+ * @mpd->inode: inode
+ * @mpd->first_page: first page of the extent
+ * @mpd->next_page: page after the last page of the extent
*
- * So, if we see any bmap calls here on a modified, data-journaled file,
- * take extra steps to flush any blocks which might be in the cache.
+ * By the time mpage_da_submit_io() is called we expect all blocks
+ * to be allocated. this may be wrong if allocation failed.
+ *
+ * As pages are already locked by write_cache_pages(), we can't use it
*/
-static sector_t ext4_bmap(struct address_space *mapping, sector_t block)
+static int mpage_da_submit_io(struct mpage_da_data *mpd)
{
- struct inode *inode = mapping->host;
- journal_t *journal;
- int err;
+ long pages_skipped;
+ struct pagevec pvec;
+ unsigned long index, end;
+ int ret = 0, err, nr_pages, i;
+ struct inode *inode = mpd->inode;
+ struct address_space *mapping = inode->i_mapping;
+
+ BUG_ON(mpd->next_page <= mpd->first_page);
+ /*
+ * We need to start from the first_page to the next_page - 1
+ * to make sure we also write the mapped dirty buffer_heads.
+ * If we look at mpd->b_blocknr we would only be looking
+ * at the currently mapped buffer_heads.
+ */
+ index = mpd->first_page;
+ end = mpd->next_page - 1;
+
+ pagevec_init(&pvec, 0);
+ while (index <= end) {
+ nr_pages = pagevec_lookup(&pvec, mapping, index, PAGEVEC_SIZE);
+ if (nr_pages == 0)
+ break;
+ for (i = 0; i < nr_pages; i++) {
+ struct page *page = pvec.pages[i];
+
+ index = page->index;
+ if (index > end)
+ break;
+ index++;
+
+ BUG_ON(!PageLocked(page));
+ BUG_ON(PageWriteback(page));
+
+ pages_skipped = mpd->wbc->pages_skipped;
+ err = mapping->a_ops->writepage(page, mpd->wbc);
+ if (!err && (pages_skipped == mpd->wbc->pages_skipped))
+ /*
+ * have successfully written the page
+ * without skipping the same
+ */
+ mpd->pages_written++;
+ /*
+ * In error case, we have to continue because
+ * remaining pages are still locked
+ * XXX: unlock and re-dirty them?
+ */
+ if (ret == 0)
+ ret = err;
+ }
+ pagevec_release(&pvec);
+ }
+ return ret;
+}
+
+/*
+ * mpage_put_bnr_to_bhs - walk blocks and assign them actual numbers
+ *
+ * @mpd->inode - inode to walk through
+ * @exbh->b_blocknr - first block on a disk
+ * @exbh->b_size - amount of space in bytes
+ * @logical - first logical block to start assignment with
+ *
+ * the function goes through all passed space and put actual disk
+ * block numbers into buffer heads, dropping BH_Delay and BH_Unwritten
+ */
+static void mpage_put_bnr_to_bhs(struct mpage_da_data *mpd, sector_t logical,
+ struct buffer_head *exbh)
+{
+ struct inode *inode = mpd->inode;
+ struct address_space *mapping = inode->i_mapping;
+ int blocks = exbh->b_size >> inode->i_blkbits;
+ sector_t pblock = exbh->b_blocknr, cur_logical;
+ struct buffer_head *head, *bh;
+ pgoff_t index, end;
+ struct pagevec pvec;
+ int nr_pages, i;
+
+ index = logical >> (PAGE_CACHE_SHIFT - inode->i_blkbits);
+ end = (logical + blocks - 1) >> (PAGE_CACHE_SHIFT - inode->i_blkbits);
+ cur_logical = index << (PAGE_CACHE_SHIFT - inode->i_blkbits);
+
+ pagevec_init(&pvec, 0);
+
+ while (index <= end) {
+ /* XXX: optimize tail */
+ nr_pages = pagevec_lookup(&pvec, mapping, index, PAGEVEC_SIZE);
+ if (nr_pages == 0)
+ break;
+ for (i = 0; i < nr_pages; i++) {
+ struct page *page = pvec.pages[i];
+
+ index = page->index;
+ if (index > end)
+ break;
+ index++;
+
+ BUG_ON(!PageLocked(page));
+ BUG_ON(PageWriteback(page));
+ BUG_ON(!page_has_buffers(page));
+
+ bh = page_buffers(page);
+ head = bh;
+
+ /* skip blocks out of the range */
+ do {
+ if (cur_logical >= logical)
+ break;
+ cur_logical++;
+ } while ((bh = bh->b_this_page) != head);
+
+ do {
+ if (cur_logical >= logical + blocks)
+ break;
+
+ if (buffer_delay(bh) ||
+ buffer_unwritten(bh)) {
+
+ BUG_ON(bh->b_bdev != inode->i_sb->s_bdev);
+
+ if (buffer_delay(bh)) {
+ clear_buffer_delay(bh);
+ bh->b_blocknr = pblock;
+ } else {
+ /*
+ * unwritten already should have
+ * blocknr assigned. Verify that
+ */
+ clear_buffer_unwritten(bh);
+ BUG_ON(bh->b_blocknr != pblock);
+ }
+
+ } else if (buffer_mapped(bh))
+ BUG_ON(bh->b_blocknr != pblock);
+
+ cur_logical++;
+ pblock++;
+ } while ((bh = bh->b_this_page) != head);
+ }
+ pagevec_release(&pvec);
+ }
+}
+
+
+/*
+ * __unmap_underlying_blocks - just a helper function to unmap
+ * set of blocks described by @bh
+ */
+static inline void __unmap_underlying_blocks(struct inode *inode,
+ struct buffer_head *bh)
+{
+ struct block_device *bdev = inode->i_sb->s_bdev;
+ int blocks, i;
+
+ blocks = bh->b_size >> inode->i_blkbits;
+ for (i = 0; i < blocks; i++)
+ unmap_underlying_metadata(bdev, bh->b_blocknr + i);
+}
+
+static void ext4_da_block_invalidatepages(struct mpage_da_data *mpd,
+ sector_t logical, long blk_cnt)
+{
+ int nr_pages, i;
+ pgoff_t index, end;
+ struct pagevec pvec;
+ struct inode *inode = mpd->inode;
+ struct address_space *mapping = inode->i_mapping;
- if (EXT4_I(inode)->i_state & EXT4_STATE_JDATA) {
+ index = logical >> (PAGE_CACHE_SHIFT - inode->i_blkbits);
+ end = (logical + blk_cnt - 1) >>
+ (PAGE_CACHE_SHIFT - inode->i_blkbits);
+ while (index <= end) {
+ nr_pages = pagevec_lookup(&pvec, mapping, index, PAGEVEC_SIZE);
+ if (nr_pages == 0)
+ break;
+ for (i = 0; i < nr_pages; i++) {
+ struct page *page = pvec.pages[i];
+ index = page->index;
+ if (index > end)
+ break;
+ index++;
+
+ BUG_ON(!PageLocked(page));
+ BUG_ON(PageWriteback(page));
+ block_invalidatepage(page, 0);
+ ClearPageUptodate(page);
+ unlock_page(page);
+ }
+ }
+ return;
+}
+
+static void ext4_print_free_blocks(struct inode *inode)
+{
+ struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
+ printk(KERN_CRIT "Total free blocks count %lld\n",
+ ext4_count_free_blocks(inode->i_sb));
+ printk(KERN_CRIT "Free/Dirty block details\n");
+ printk(KERN_CRIT "free_blocks=%lld\n",
+ (long long) percpu_counter_sum(&sbi->s_freeblocks_counter));
+ printk(KERN_CRIT "dirty_blocks=%lld\n",
+ (long long) percpu_counter_sum(&sbi->s_dirtyblocks_counter));
+ printk(KERN_CRIT "Block reservation details\n");
+ printk(KERN_CRIT "i_reserved_data_blocks=%u\n",
+ EXT4_I(inode)->i_reserved_data_blocks);
+ printk(KERN_CRIT "i_reserved_meta_blocks=%u\n",
+ EXT4_I(inode)->i_reserved_meta_blocks);
+ return;
+}
+
+/*
+ * mpage_da_map_blocks - go through given space
+ *
+ * @mpd - bh describing space
+ *
+ * The function skips space we know is already mapped to disk blocks.
+ *
+ */
+static int mpage_da_map_blocks(struct mpage_da_data *mpd)
+{
+ int err, blks, get_blocks_flags;
+ struct buffer_head new;
+ sector_t next = mpd->b_blocknr;
+ unsigned max_blocks = mpd->b_size >> mpd->inode->i_blkbits;
+ loff_t disksize = EXT4_I(mpd->inode)->i_disksize;
+ handle_t *handle = NULL;
+
+ /*
+ * We consider only non-mapped and non-allocated blocks
+ */
+ if ((mpd->b_state & (1 << BH_Mapped)) &&
+ !(mpd->b_state & (1 << BH_Delay)) &&
+ !(mpd->b_state & (1 << BH_Unwritten)))
+ return 0;
+
+ /*
+ * If we didn't accumulate anything to write simply return
+ */
+ if (!mpd->b_size)
+ return 0;
+
+ handle = ext4_journal_current_handle();
+ BUG_ON(!handle);
+
+ /*
+ * Call ext4_get_blocks() to allocate any delayed allocation
+ * blocks, or to convert an uninitialized extent to be
+ * initialized (in the case where we have written into
+ * one or more preallocated blocks).
+ *
+ * We pass in the magic EXT4_GET_BLOCKS_DELALLOC_RESERVE to
+ * indicate that we are on the delayed allocation path. This
+ * affects functions in many different parts of the allocation
+ * call path. This flag exists primarily because we don't
+ * want to change *many* call functions, so ext4_get_blocks()
+ * will set the magic i_delalloc_reserved_flag once the
+ * inode's allocation semaphore is taken.
+ *
+ * If the blocks in questions were delalloc blocks, set
+ * EXT4_GET_BLOCKS_DELALLOC_RESERVE so the delalloc accounting
+ * variables are updated after the blocks have been allocated.
+ */
+ new.b_state = 0;
+ get_blocks_flags = (EXT4_GET_BLOCKS_CREATE |
+ EXT4_GET_BLOCKS_DELALLOC_RESERVE);
+ if (mpd->b_state & (1 << BH_Delay))
+ get_blocks_flags |= EXT4_GET_BLOCKS_UPDATE_RESERVE_SPACE;
+ blks = ext4_get_blocks(handle, mpd->inode, next, max_blocks,
+ &new, get_blocks_flags);
+ if (blks < 0) {
+ err = blks;
/*
- * This is a REALLY heavyweight approach, but the use of
- * bmap on dirty files is expected to be extremely rare:
- * only if we run lilo or swapon on a freshly made file
- * do we expect this to happen.
- *
- * (bmap requires CAP_SYS_RAWIO so this does not
- * represent an unprivileged user DOS attack --- we'd be
- * in trouble if mortal users could trigger this path at
- * will.)
- *
- * NB. EXT4_STATE_JDATA is not set on files other than
- * regular files. If somebody wants to bmap a directory
- * or symlink and gets confused because the buffer
- * hasn't yet been flushed to disk, they deserve
- * everything they get.
+ * If get block returns with error we simply
+ * return. Later writepage will redirty the page and
+ * writepages will find the dirty page again
*/
+ if (err == -EAGAIN)
+ return 0;
- EXT4_I(inode)->i_state &= ~EXT4_STATE_JDATA;
- journal = EXT4_JOURNAL(inode);
- jbd2_journal_lock_updates(journal);
- err = jbd2_journal_flush(journal);
- jbd2_journal_unlock_updates(journal);
+ if (err == -ENOSPC &&
+ ext4_count_free_blocks(mpd->inode->i_sb)) {
+ mpd->retval = err;
+ return 0;
+ }
+
+ /*
+ * get block failure will cause us to loop in
+ * writepages, because a_ops->writepage won't be able
+ * to make progress. The page will be redirtied by
+ * writepage and writepages will again try to write
+ * the same.
+ */
+ ext4_msg(mpd->inode->i_sb, KERN_CRIT,
+ "delayed block allocation failed for inode %lu at "
+ "logical offset %llu with max blocks %zd with "
+ "error %d\n", mpd->inode->i_ino,
+ (unsigned long long) next,
+ mpd->b_size >> mpd->inode->i_blkbits, err);
+ printk(KERN_CRIT "This should not happen!! "
+ "Data will be lost\n");
+ if (err == -ENOSPC) {
+ ext4_print_free_blocks(mpd->inode);
+ }
+ /* invalidate all the pages */
+ ext4_da_block_invalidatepages(mpd, next,
+ mpd->b_size >> mpd->inode->i_blkbits);
+ return err;
+ }
+ BUG_ON(blks == 0);
+ new.b_size = (blks << mpd->inode->i_blkbits);
+
+ if (buffer_new(&new))
+ __unmap_underlying_blocks(mpd->inode, &new);
+
+ /*
+ * If blocks are delayed marked, we need to
+ * put actual blocknr and drop delayed bit
+ */
+ if ((mpd->b_state & (1 << BH_Delay)) ||
+ (mpd->b_state & (1 << BH_Unwritten)))
+ mpage_put_bnr_to_bhs(mpd, next, &new);
+
+ if (ext4_should_order_data(mpd->inode)) {
+ err = ext4_jbd2_file_inode(handle, mpd->inode);
if (err)
- return 0;
+ return err;
+ }
+
+ /*
+ * Update on-disk size along with block allocation.
+ */
+ disksize = ((loff_t) next + blks) << mpd->inode->i_blkbits;
+ if (disksize > i_size_read(mpd->inode))
+ disksize = i_size_read(mpd->inode);
+ if (disksize > EXT4_I(mpd->inode)->i_disksize) {
+ ext4_update_i_disksize(mpd->inode, disksize);
+ return ext4_mark_inode_dirty(handle, mpd->inode);
+ }
+
+ return 0;
+}
+
+#define BH_FLAGS ((1 << BH_Uptodate) | (1 << BH_Mapped) | \
+ (1 << BH_Delay) | (1 << BH_Unwritten))
+
+/*
+ * mpage_add_bh_to_extent - try to add one more block to extent of blocks
+ *
+ * @mpd->lbh - extent of blocks
+ * @logical - logical number of the block in the file
+ * @bh - bh of the block (used to access block's state)
+ *
+ * the function is used to collect contig. blocks in same state
+ */
+static void mpage_add_bh_to_extent(struct mpage_da_data *mpd,
+ sector_t logical, size_t b_size,
+ unsigned long b_state)
+{
+ sector_t next;
+ int nrblocks = mpd->b_size >> mpd->inode->i_blkbits;
+
+ /* check if thereserved journal credits might overflow */
+ if (!(EXT4_I(mpd->inode)->i_flags & EXT4_EXTENTS_FL)) {
+ if (nrblocks >= EXT4_MAX_TRANS_DATA) {
+ /*
+ * With non-extent format we are limited by the journal
+ * credit available. Total credit needed to insert
+ * nrblocks contiguous blocks is dependent on the
+ * nrblocks. So limit nrblocks.
+ */
+ goto flush_it;
+ } else if ((nrblocks + (b_size >> mpd->inode->i_blkbits)) >
+ EXT4_MAX_TRANS_DATA) {
+ /*
+ * Adding the new buffer_head would make it cross the
+ * allowed limit for which we have journal credit
+ * reserved. So limit the new bh->b_size
+ */
+ b_size = (EXT4_MAX_TRANS_DATA - nrblocks) <<
+ mpd->inode->i_blkbits;
+ /* we will do mpage_da_submit_io in the next loop */
+ }
+ }
+ /*
+ * First block in the extent
+ */
+ if (mpd->b_size == 0) {
+ mpd->b_blocknr = logical;
+ mpd->b_size = b_size;
+ mpd->b_state = b_state & BH_FLAGS;
+ return;
+ }
+
+ next = mpd->b_blocknr + nrblocks;
+ /*
+ * Can we merge the block to our big extent?
+ */
+ if (logical == next && (b_state & BH_FLAGS) == mpd->b_state) {
+ mpd->b_size += b_size;
+ return;
+ }
+
+flush_it:
+ /*
+ * We couldn't merge the block to our extent, so we
+ * need to flush current extent and start new one
+ */
+ if (mpage_da_map_blocks(mpd) == 0)
+ mpage_da_submit_io(mpd);
+ mpd->io_done = 1;
+ return;
+}
+
+static int ext4_bh_delay_or_unwritten(handle_t *handle, struct buffer_head *bh)
+{
+ return (buffer_delay(bh) || buffer_unwritten(bh)) && buffer_dirty(bh);
+}
+
+/*
+ * __mpage_da_writepage - finds extent of pages and blocks
+ *
+ * @page: page to consider
+ * @wbc: not used, we just follow rules
+ * @data: context
+ *
+ * The function finds extents of pages and scan them for all blocks.
+ */
+static int __mpage_da_writepage(struct page *page,
+ struct writeback_control *wbc, void *data)
+{
+ struct mpage_da_data *mpd = data;
+ struct inode *inode = mpd->inode;
+ struct buffer_head *bh, *head;
+ sector_t logical;
+
+ if (mpd->io_done) {
+ /*
+ * Rest of the page in the page_vec
+ * redirty then and skip then. We will
+ * try to write them again after
+ * starting a new transaction
+ */
+ redirty_page_for_writepage(wbc, page);
+ unlock_page(page);
+ return MPAGE_DA_EXTENT_TAIL;
+ }
+ /*
+ * Can we merge this page to current extent?
+ */
+ if (mpd->next_page != page->index) {
+ /*
+ * Nope, we can't. So, we map non-allocated blocks
+ * and start IO on them using writepage()
+ */
+ if (mpd->next_page != mpd->first_page) {
+ if (mpage_da_map_blocks(mpd) == 0)
+ mpage_da_submit_io(mpd);
+ /*
+ * skip rest of the page in the page_vec
+ */
+ mpd->io_done = 1;
+ redirty_page_for_writepage(wbc, page);
+ unlock_page(page);
+ return MPAGE_DA_EXTENT_TAIL;
+ }
+
+ /*
+ * Start next extent of pages ...
+ */
+ mpd->first_page = page->index;
+
+ /*
+ * ... and blocks
+ */
+ mpd->b_size = 0;
+ mpd->b_state = 0;
+ mpd->b_blocknr = 0;
}
- return generic_block_bmap(mapping,block,ext4_get_block);
+ mpd->next_page = page->index + 1;
+ logical = (sector_t) page->index <<
+ (PAGE_CACHE_SHIFT - inode->i_blkbits);
+
+ if (!page_has_buffers(page)) {
+ mpage_add_bh_to_extent(mpd, logical, PAGE_CACHE_SIZE,
+ (1 << BH_Dirty) | (1 << BH_Uptodate));
+ if (mpd->io_done)
+ return MPAGE_DA_EXTENT_TAIL;
+ } else {
+ /*
+ * Page with regular buffer heads, just add all dirty ones
+ */
+ head = page_buffers(page);
+ bh = head;
+ do {
+ BUG_ON(buffer_locked(bh));
+ /*
+ * We need to try to allocate
+ * unmapped blocks in the same page.
+ * Otherwise we won't make progress
+ * with the page in ext4_writepage
+ */
+ if (ext4_bh_delay_or_unwritten(NULL, bh)) {
+ mpage_add_bh_to_extent(mpd, logical,
+ bh->b_size,
+ bh->b_state);
+ if (mpd->io_done)
+ return MPAGE_DA_EXTENT_TAIL;
+ } else if (buffer_dirty(bh) && (buffer_mapped(bh))) {
+ /*
+ * mapped dirty buffer. We need to update
+ * the b_state because we look at
+ * b_state in mpage_da_map_blocks. We don't
+ * update b_size because if we find an
+ * unmapped buffer_head later we need to
+ * use the b_state flag of that buffer_head.
+ */
+ if (mpd->b_size == 0)
+ mpd->b_state = bh->b_state & BH_FLAGS;
+ }
+ logical++;
+ } while ((bh = bh->b_this_page) != head);
+ }
+
+ return 0;
+}
+
+/*
+ * This is a special get_blocks_t callback which is used by
+ * ext4_da_write_begin(). It will either return mapped block or
+ * reserve space for a single block.
+ *
+ * For delayed buffer_head we have BH_Mapped, BH_New, BH_Delay set.
+ * We also have b_blocknr = -1 and b_bdev initialized properly
+ *
+ * For unwritten buffer_head we have BH_Mapped, BH_New, BH_Unwritten set.
+ * We also have b_blocknr = physicalblock mapping unwritten extent and b_bdev
+ * initialized properly.
+ */
+static int ext4_da_get_block_prep(struct inode *inode, sector_t iblock,
+ struct buffer_head *bh_result, int create)
+{
+ int ret = 0;
+ sector_t invalid_block = ~((sector_t) 0xffff);
+
+ if (invalid_block < ext4_blocks_count(EXT4_SB(inode->i_sb)->s_es))
+ invalid_block = ~0;
+
+ BUG_ON(create == 0);
+ BUG_ON(bh_result->b_size != inode->i_sb->s_blocksize);
+
+ /*
+ * first, we need to know whether the block is allocated already
+ * preallocated blocks are unmapped but should treated
+ * the same as allocated blocks.
+ */
+ ret = ext4_get_blocks(NULL, inode, iblock, 1, bh_result, 0);
+ if ((ret == 0) && !buffer_delay(bh_result)) {
+ /* the block isn't (pre)allocated yet, let's reserve space */
+ /*
+ * XXX: __block_prepare_write() unmaps passed block,
+ * is it OK?
+ */
+ ret = ext4_da_reserve_space(inode, 1);
+ if (ret)
+ /* not enough space to reserve */
+ return ret;
+
+ map_bh(bh_result, inode->i_sb, invalid_block);
+ set_buffer_new(bh_result);
+ set_buffer_delay(bh_result);
+ } else if (ret > 0) {
+ bh_result->b_size = (ret << inode->i_blkbits);
+ if (buffer_unwritten(bh_result)) {
+ /* A delayed write to unwritten bh should
+ * be marked new and mapped. Mapped ensures
+ * that we don't do get_block multiple times
+ * when we write to the same offset and new
+ * ensures that we do proper zero out for
+ * partial write.
+ */
+ set_buffer_new(bh_result);
+ set_buffer_mapped(bh_result);
+ }
+ ret = 0;
+ }
+
+ return ret;
+}
+
+/*
+ * This function is used as a standard get_block_t calback function
+ * when there is no desire to allocate any blocks. It is used as a
+ * callback function for block_prepare_write(), nobh_writepage(), and
+ * block_write_full_page(). These functions should only try to map a
+ * single block at a time.
+ *
+ * Since this function doesn't do block allocations even if the caller
+ * requests it by passing in create=1, it is critically important that
+ * any caller checks to make sure that any buffer heads are returned
+ * by this function are either all already mapped or marked for
+ * delayed allocation before calling nobh_writepage() or
+ * block_write_full_page(). Otherwise, b_blocknr could be left
+ * unitialized, and the page write functions will be taken by
+ * surprise.
+ */
+static int noalloc_get_block_write(struct inode *inode, sector_t iblock,
+ struct buffer_head *bh_result, int create)
+{
+ int ret = 0;
+ unsigned max_blocks = bh_result->b_size >> inode->i_blkbits;
+
+ BUG_ON(bh_result->b_size != inode->i_sb->s_blocksize);
+
+ /*
+ * we don't want to do block allocation in writepage
+ * so call get_block_wrap with create = 0
+ */
+ ret = ext4_get_blocks(NULL, inode, iblock, max_blocks, bh_result, 0);
+ if (ret > 0) {
+ bh_result->b_size = (ret << inode->i_blkbits);
+ ret = 0;
+ }
+ return ret;
}
static int bget_one(handle_t *handle, struct buffer_head *bh)
return 0;
}
-static int jbd2_journal_dirty_data_fn(handle_t *handle, struct buffer_head *bh)
+static int __ext4_journalled_writepage(struct page *page,
+ struct writeback_control *wbc,
+ unsigned int len)
{
- if (buffer_mapped(bh))
- return ext4_journal_dirty_data(handle, bh);
- return 0;
+ struct address_space *mapping = page->mapping;
+ struct inode *inode = mapping->host;
+ struct buffer_head *page_bufs;
+ handle_t *handle = NULL;
+ int ret = 0;
+ int err;
+
+ page_bufs = page_buffers(page);
+ BUG_ON(!page_bufs);
+ walk_page_buffers(handle, page_bufs, 0, len, NULL, bget_one);
+ /* As soon as we unlock the page, it can go away, but we have
+ * references to buffers so we are safe */
+ unlock_page(page);
+
+ handle = ext4_journal_start(inode, ext4_writepage_trans_blocks(inode));
+ if (IS_ERR(handle)) {
+ ret = PTR_ERR(handle);
+ goto out;
+ }
+
+ ret = walk_page_buffers(handle, page_bufs, 0, len, NULL,
+ do_journal_get_write_access);
+
+ err = walk_page_buffers(handle, page_bufs, 0, len, NULL,
+ write_end_fn);
+ if (ret == 0)
+ ret = err;
+ err = ext4_journal_stop(handle);
+ if (!ret)
+ ret = err;
+
+ walk_page_buffers(handle, page_bufs, 0, len, NULL, bput_one);
+ EXT4_I(inode)->i_state |= EXT4_STATE_JDATA;
+out:
+ return ret;
}
/*
- * Note that we always start a transaction even if we're not journalling
- * data. This is to preserve ordering: any hole instantiation within
- * __block_write_full_page -> ext4_get_block() should be journalled
- * along with the data so we don't crash and then get metadata which
- * refers to old data.
- *
- * In all journalling modes block_write_full_page() will start the I/O.
- *
- * Problem:
- *
- * ext4_writepage() -> kmalloc() -> __alloc_pages() -> page_launder() ->
- * ext4_writepage()
- *
- * Similar for:
+ * Note that we don't need to start a transaction unless we're journaling data
+ * because we should have holes filled from ext4_page_mkwrite(). We even don't
+ * need to file the inode to the transaction's list in ordered mode because if
+ * we are writing back data added by write(), the inode is already there and if
+ * we are writing back data modified via mmap(), noone guarantees in which
+ * transaction the data will hit the disk. In case we are journaling data, we
+ * cannot start transaction directly because transaction start ranks above page
+ * lock so we have to do some magic.
*
- * ext4_file_write() -> generic_file_write() -> __alloc_pages() -> ...
+ * This function can get called via...
+ * - ext4_da_writepages after taking page lock (have journal handle)
+ * - journal_submit_inode_data_buffers (no journal handle)
+ * - shrink_page_list via pdflush (no journal handle)
+ * - grab_page_cache when doing write_begin (have journal handle)
*
- * Same applies to ext4_get_block(). We will deadlock on various things like
- * lock_journal and i_data_sem
+ * We don't do any block allocation in this function. If we have page with
+ * multiple blocks we need to write those buffer_heads that are mapped. This
+ * is important for mmaped based write. So if we do with blocksize 1K
+ * truncate(f, 1024);
+ * a = mmap(f, 0, 4096);
+ * a[0] = 'a';
+ * truncate(f, 4096);
+ * we have in the page first buffer_head mapped via page_mkwrite call back
+ * but other bufer_heads would be unmapped but dirty(dirty done via the
+ * do_wp_page). So writepage should write the first block. If we modify
+ * the mmap area beyond 1024 we will again get a page_fault and the
+ * page_mkwrite callback will do the block allocation and mark the
+ * buffer_heads mapped.
*
- * Setting PF_MEMALLOC here doesn't work - too many internal memory
- * allocations fail.
+ * We redirty the page if we have any buffer_heads that is either delay or
+ * unwritten in the page.
*
- * 16May01: If we're reentered then journal_current_handle() will be
- * non-zero. We simply *return*.
+ * We can get recursively called as show below.
*
- * 1 July 2001: @@@ FIXME:
- * In journalled data mode, a data buffer may be metadata against the
- * current transaction. But the same file is part of a shared mapping
- * and someone does a writepage() on it.
- *
- * We will move the buffer onto the async_data list, but *after* it has
- * been dirtied. So there's a small window where we have dirty data on
- * BJ_Metadata.
- *
- * Note that this only applies to the last partial page in the file. The
- * bit which block_write_full_page() uses prepare/commit for. (That's
- * broken code anyway: it's wrong for msync()).
- *
- * It's a rare case: affects the final partial page, for journalled data
- * where the file is subject to bith write() and writepage() in the same
- * transction. To fix it we'll need a custom block_write_full_page().
- * We'll probably need that anyway for journalling writepage() output.
- *
- * We don't honour synchronous mounts for writepage(). That would be
- * disastrous. Any write() or metadata operation will sync the fs for
- * us.
+ * ext4_writepage() -> kmalloc() -> __alloc_pages() -> page_launder() ->
+ * ext4_writepage()
*
- * AKPM2: if all the page's buffers are mapped to disk and !data=journal,
- * we don't need to open a transaction here.
+ * But since we don't do any block allocation we should not deadlock.
+ * Page also have the dirty flag cleared so we don't get recurive page_lock.
*/
-static int ext4_ordered_writepage(struct page *page,
- struct writeback_control *wbc)
+static int ext4_writepage(struct page *page,
+ struct writeback_control *wbc)
{
- struct inode *inode = page->mapping->host;
+ int ret = 0;
+ loff_t size;
+ unsigned int len;
struct buffer_head *page_bufs;
+ struct inode *inode = page->mapping->host;
+
+ trace_ext4_writepage(inode, page);
+ size = i_size_read(inode);
+ if (page->index == size >> PAGE_CACHE_SHIFT)
+ len = size & ~PAGE_CACHE_MASK;
+ else
+ len = PAGE_CACHE_SIZE;
+
+ if (page_has_buffers(page)) {
+ page_bufs = page_buffers(page);
+ if (walk_page_buffers(NULL, page_bufs, 0, len, NULL,
+ ext4_bh_delay_or_unwritten)) {
+ /*
+ * We don't want to do block allocation
+ * So redirty the page and return
+ * We may reach here when we do a journal commit
+ * via journal_submit_inode_data_buffers.
+ * If we don't have mapping block we just ignore
+ * them. We can also reach here via shrink_page_list
+ */
+ redirty_page_for_writepage(wbc, page);
+ unlock_page(page);
+ return 0;
+ }
+ } else {
+ /*
+ * The test for page_has_buffers() is subtle:
+ * We know the page is dirty but it lost buffers. That means
+ * that at some moment in time after write_begin()/write_end()
+ * has been called all buffers have been clean and thus they
+ * must have been written at least once. So they are all
+ * mapped and we can happily proceed with mapping them
+ * and writing the page.
+ *
+ * Try to initialize the buffer_heads and check whether
+ * all are mapped and non delay. We don't want to
+ * do block allocation here.
+ */
+ ret = block_prepare_write(page, 0, len,
+ noalloc_get_block_write);
+ if (!ret) {
+ page_bufs = page_buffers(page);
+ /* check whether all are mapped and non delay */
+ if (walk_page_buffers(NULL, page_bufs, 0, len, NULL,
+ ext4_bh_delay_or_unwritten)) {
+ redirty_page_for_writepage(wbc, page);
+ unlock_page(page);
+ return 0;
+ }
+ } else {
+ /*
+ * We can't do block allocation here
+ * so just redity the page and unlock
+ * and return
+ */
+ redirty_page_for_writepage(wbc, page);
+ unlock_page(page);
+ return 0;
+ }
+ /* now mark the buffer_heads as dirty and uptodate */
+ block_commit_write(page, 0, len);
+ }
+
+ if (PageChecked(page) && ext4_should_journal_data(inode)) {
+ /*
+ * It's mmapped pagecache. Add buffers and journal it. There
+ * doesn't seem much point in redirtying the page here.
+ */
+ ClearPageChecked(page);
+ return __ext4_journalled_writepage(page, wbc, len);
+ }
+
+ if (test_opt(inode->i_sb, NOBH) && ext4_should_writeback_data(inode))
+ ret = nobh_writepage(page, noalloc_get_block_write, wbc);
+ else
+ ret = block_write_full_page(page, noalloc_get_block_write,
+ wbc);
+
+ return ret;
+}
+
+/*
+ * This is called via ext4_da_writepages() to
+ * calulate the total number of credits to reserve to fit
+ * a single extent allocation into a single transaction,
+ * ext4_da_writpeages() will loop calling this before
+ * the block allocation.
+ */
+
+static int ext4_da_writepages_trans_blocks(struct inode *inode)
+{
+ int max_blocks = EXT4_I(inode)->i_reserved_data_blocks;
+
+ /*
+ * With non-extent format the journal credit needed to
+ * insert nrblocks contiguous block is dependent on
+ * number of contiguous block. So we will limit
+ * number of contiguous block to a sane value
+ */
+ if (!(inode->i_flags & EXT4_EXTENTS_FL) &&
+ (max_blocks > EXT4_MAX_TRANS_DATA))
+ max_blocks = EXT4_MAX_TRANS_DATA;
+
+ return ext4_chunk_trans_blocks(inode, max_blocks);
+}
+
+static int ext4_da_writepages(struct address_space *mapping,
+ struct writeback_control *wbc)
+{
+ pgoff_t index;
+ int range_whole = 0;
handle_t *handle = NULL;
- int ret = 0;
- int err;
+ struct mpage_da_data mpd;
+ struct inode *inode = mapping->host;
+ int no_nrwrite_index_update;
+ int pages_written = 0;
+ long pages_skipped;
+ unsigned int max_pages;
+ int range_cyclic, cycled = 1, io_done = 0;
+ int needed_blocks, ret = 0;
+ long desired_nr_to_write, nr_to_writebump = 0;
+ loff_t range_start = wbc->range_start;
+ struct ext4_sb_info *sbi = EXT4_SB(mapping->host->i_sb);
+
+ trace_ext4_da_writepages(inode, wbc);
- J_ASSERT(PageLocked(page));
+ /*
+ * No pages to write? This is mainly a kludge to avoid starting
+ * a transaction for special inodes like journal inode on last iput()
+ * because that could violate lock ordering on umount
+ */
+ if (!mapping->nrpages || !mapping_tagged(mapping, PAGECACHE_TAG_DIRTY))
+ return 0;
/*
- * We give up here if we're reentered, because it might be for a
- * different filesystem.
+ * If the filesystem has aborted, it is read-only, so return
+ * right away instead of dumping stack traces later on that
+ * will obscure the real source of the problem. We test
+ * EXT4_MF_FS_ABORTED instead of sb->s_flag's MS_RDONLY because
+ * the latter could be true if the filesystem is mounted
+ * read-only, and in that case, ext4_da_writepages should
+ * *never* be called, so if that ever happens, we would want
+ * the stack trace.
*/
- if (ext4_journal_current_handle())
- goto out_fail;
+ if (unlikely(sbi->s_mount_flags & EXT4_MF_FS_ABORTED))
+ return -EROFS;
- handle = ext4_journal_start(inode, ext4_writepage_trans_blocks(inode));
+ if (wbc->range_start == 0 && wbc->range_end == LLONG_MAX)
+ range_whole = 1;
+
+ range_cyclic = wbc->range_cyclic;
+ if (wbc->range_cyclic) {
+ index = mapping->writeback_index;
+ if (index)
+ cycled = 0;
+ wbc->range_start = index << PAGE_CACHE_SHIFT;
+ wbc->range_end = LLONG_MAX;
+ wbc->range_cyclic = 0;
+ } else
+ index = wbc->range_start >> PAGE_CACHE_SHIFT;
+
+ /*
+ * This works around two forms of stupidity. The first is in
+ * the writeback code, which caps the maximum number of pages
+ * written to be 1024 pages. This is wrong on multiple
+ * levels; different architectues have a different page size,
+ * which changes the maximum amount of data which gets
+ * written. Secondly, 4 megabytes is way too small. XFS
+ * forces this value to be 16 megabytes by multiplying
+ * nr_to_write parameter by four, and then relies on its
+ * allocator to allocate larger extents to make them
+ * contiguous. Unfortunately this brings us to the second
+ * stupidity, which is that ext4's mballoc code only allocates
+ * at most 2048 blocks. So we force contiguous writes up to
+ * the number of dirty blocks in the inode, or
+ * sbi->max_writeback_mb_bump whichever is smaller.
+ */
+ max_pages = sbi->s_max_writeback_mb_bump << (20 - PAGE_CACHE_SHIFT);
+ if (!range_cyclic && range_whole)
+ desired_nr_to_write = wbc->nr_to_write * 8;
+ else
+ desired_nr_to_write = ext4_num_dirty_pages(inode, index,
+ max_pages);
+ if (desired_nr_to_write > max_pages)
+ desired_nr_to_write = max_pages;
+
+ if (wbc->nr_to_write < desired_nr_to_write) {
+ nr_to_writebump = desired_nr_to_write - wbc->nr_to_write;
+ wbc->nr_to_write = desired_nr_to_write;
+ }
+
+ mpd.wbc = wbc;
+ mpd.inode = mapping->host;
+
+ /*
+ * we don't want write_cache_pages to update
+ * nr_to_write and writeback_index
+ */
+ no_nrwrite_index_update = wbc->no_nrwrite_index_update;
+ wbc->no_nrwrite_index_update = 1;
+ pages_skipped = wbc->pages_skipped;
+
+retry:
+ while (!ret && wbc->nr_to_write > 0) {
+
+ /*
+ * we insert one extent at a time. So we need
+ * credit needed for single extent allocation.
+ * journalled mode is currently not supported
+ * by delalloc
+ */
+ BUG_ON(ext4_should_journal_data(inode));
+ needed_blocks = ext4_da_writepages_trans_blocks(inode);
+
+ /* start a new transaction*/
+ handle = ext4_journal_start(inode, needed_blocks);
+ if (IS_ERR(handle)) {
+ ret = PTR_ERR(handle);
+ ext4_msg(inode->i_sb, KERN_CRIT, "%s: jbd2_start: "
+ "%ld pages, ino %lu; err %d\n", __func__,
+ wbc->nr_to_write, inode->i_ino, ret);
+ goto out_writepages;
+ }
+
+ /*
+ * Now call __mpage_da_writepage to find the next
+ * contiguous region of logical blocks that need
+ * blocks to be allocated by ext4. We don't actually
+ * submit the blocks for I/O here, even though
+ * write_cache_pages thinks it will, and will set the
+ * pages as clean for write before calling
+ * __mpage_da_writepage().
+ */
+ mpd.b_size = 0;
+ mpd.b_state = 0;
+ mpd.b_blocknr = 0;
+ mpd.first_page = 0;
+ mpd.next_page = 0;
+ mpd.io_done = 0;
+ mpd.pages_written = 0;
+ mpd.retval = 0;
+ ret = write_cache_pages(mapping, wbc, __mpage_da_writepage,
+ &mpd);
+ /*
+ * If we have a contiguous extent of pages and we
+ * haven't done the I/O yet, map the blocks and submit
+ * them for I/O.
+ */
+ if (!mpd.io_done && mpd.next_page != mpd.first_page) {
+ if (mpage_da_map_blocks(&mpd) == 0)
+ mpage_da_submit_io(&mpd);
+ mpd.io_done = 1;
+ ret = MPAGE_DA_EXTENT_TAIL;
+ }
+ trace_ext4_da_write_pages(inode, &mpd);
+ wbc->nr_to_write -= mpd.pages_written;
+
+ ext4_journal_stop(handle);
+ if ((mpd.retval == -ENOSPC) && sbi->s_journal) {
+ /* commit the transaction which would
+ * free blocks released in the transaction
+ * and try again
+ */
+ jbd2_journal_force_commit_nested(sbi->s_journal);
+ wbc->pages_skipped = pages_skipped;
+ ret = 0;
+ } else if (ret == MPAGE_DA_EXTENT_TAIL) {
+ /*
+ * got one extent now try with
+ * rest of the pages
+ */
+ pages_written += mpd.pages_written;
+ wbc->pages_skipped = pages_skipped;
+ ret = 0;
+ io_done = 1;
+ } else if (wbc->nr_to_write)
+ /*
+ * There is no more writeout needed
+ * or we requested for a noblocking writeout
+ * and we found the device congested
+ */
+ break;
+ }
+ if (!io_done && !cycled) {
+ cycled = 1;
+ index = 0;
+ wbc->range_start = index << PAGE_CACHE_SHIFT;
+ wbc->range_end = mapping->writeback_index - 1;
+ goto retry;
+ }
+ if (pages_skipped != wbc->pages_skipped)
+ ext4_msg(inode->i_sb, KERN_CRIT,
+ "This should not happen leaving %s "
+ "with nr_to_write = %ld ret = %d\n",
+ __func__, wbc->nr_to_write, ret);
+
+ /* Update index */
+ index += pages_written;
+ wbc->range_cyclic = range_cyclic;
+ if (wbc->range_cyclic || (range_whole && wbc->nr_to_write > 0))
+ /*
+ * set the writeback_index so that range_cyclic
+ * mode will write it back later
+ */
+ mapping->writeback_index = index;
+
+out_writepages:
+ if (!no_nrwrite_index_update)
+ wbc->no_nrwrite_index_update = 0;
+ if (wbc->nr_to_write > nr_to_writebump)
+ wbc->nr_to_write -= nr_to_writebump;
+ wbc->range_start = range_start;
+ trace_ext4_da_writepages_result(inode, wbc, ret, pages_written);
+ return ret;
+}
+
+#define FALL_BACK_TO_NONDELALLOC 1
+static int ext4_nonda_switch(struct super_block *sb)
+{
+ s64 free_blocks, dirty_blocks;
+ struct ext4_sb_info *sbi = EXT4_SB(sb);
+
+ /*
+ * switch to non delalloc mode if we are running low
+ * on free block. The free block accounting via percpu
+ * counters can get slightly wrong with percpu_counter_batch getting
+ * accumulated on each CPU without updating global counters
+ * Delalloc need an accurate free block accounting. So switch
+ * to non delalloc when we are near to error range.
+ */
+ free_blocks = percpu_counter_read_positive(&sbi->s_freeblocks_counter);
+ dirty_blocks = percpu_counter_read_positive(&sbi->s_dirtyblocks_counter);
+ if (2 * free_blocks < 3 * dirty_blocks ||
+ free_blocks < (dirty_blocks + EXT4_FREEBLOCKS_WATERMARK)) {
+ /*
+ * free block count is less that 150% of dirty blocks
+ * or free blocks is less that watermark
+ */
+ return 1;
+ }
+ return 0;
+}
+
+static int ext4_da_write_begin(struct file *file, struct address_space *mapping,
+ loff_t pos, unsigned len, unsigned flags,
+ struct page **pagep, void **fsdata)
+{
+ int ret, retries = 0;
+ struct page *page;
+ pgoff_t index;
+ unsigned from, to;
+ struct inode *inode = mapping->host;
+ handle_t *handle;
+
+ index = pos >> PAGE_CACHE_SHIFT;
+ from = pos & (PAGE_CACHE_SIZE - 1);
+ to = from + len;
+
+ if (ext4_nonda_switch(inode->i_sb)) {
+ *fsdata = (void *)FALL_BACK_TO_NONDELALLOC;
+ return ext4_write_begin(file, mapping, pos,
+ len, flags, pagep, fsdata);
+ }
+ *fsdata = (void *)0;
+ trace_ext4_da_write_begin(inode, pos, len, flags);
+retry:
+ /*
+ * With delayed allocation, we don't log the i_disksize update
+ * if there is delayed block allocation. But we still need
+ * to journalling the i_disksize update if writes to the end
+ * of file which has an already mapped buffer.
+ */
+ handle = ext4_journal_start(inode, 1);
if (IS_ERR(handle)) {
ret = PTR_ERR(handle);
- goto out_fail;
+ goto out;
+ }
+ /* We cannot recurse into the filesystem as the transaction is already
+ * started */
+ flags |= AOP_FLAG_NOFS;
+
+ page = grab_cache_page_write_begin(mapping, index, flags);
+ if (!page) {
+ ext4_journal_stop(handle);
+ ret = -ENOMEM;
+ goto out;
}
+ *pagep = page;
+
+ ret = block_write_begin(file, mapping, pos, len, flags, pagep, fsdata,
+ ext4_da_get_block_prep);
+ if (ret < 0) {
+ unlock_page(page);
+ ext4_journal_stop(handle);
+ page_cache_release(page);
+ /*
+ * block_write_begin may have instantiated a few blocks
+ * outside i_size. Trim these off again. Don't need
+ * i_size_read because we hold i_mutex.
+ */
+ if (pos + len > inode->i_size)
+ ext4_truncate(inode);
+ }
+
+ if (ret == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries))
+ goto retry;
+out:
+ return ret;
+}
+
+/*
+ * Check if we should update i_disksize
+ * when write to the end of file but not require block allocation
+ */
+static int ext4_da_should_update_i_disksize(struct page *page,
+ unsigned long offset)
+{
+ struct buffer_head *bh;
+ struct inode *inode = page->mapping->host;
+ unsigned int idx;
+ int i;
+
+ bh = page_buffers(page);
+ idx = offset >> inode->i_blkbits;
+
+ for (i = 0; i < idx; i++)
+ bh = bh->b_this_page;
- if (!page_has_buffers(page)) {
- create_empty_buffers(page, inode->i_sb->s_blocksize,
- (1 << BH_Dirty)|(1 << BH_Uptodate));
+ if (!buffer_mapped(bh) || (buffer_delay(bh)) || buffer_unwritten(bh))
+ return 0;
+ return 1;
+}
+
+static int ext4_da_write_end(struct file *file,
+ struct address_space *mapping,
+ loff_t pos, unsigned len, unsigned copied,
+ struct page *page, void *fsdata)
+{
+ struct inode *inode = mapping->host;
+ int ret = 0, ret2;
+ handle_t *handle = ext4_journal_current_handle();
+ loff_t new_i_size;
+ unsigned long start, end;
+ int write_mode = (int)(unsigned long)fsdata;
+
+ if (write_mode == FALL_BACK_TO_NONDELALLOC) {
+ if (ext4_should_order_data(inode)) {
+ return ext4_ordered_write_end(file, mapping, pos,
+ len, copied, page, fsdata);
+ } else if (ext4_should_writeback_data(inode)) {
+ return ext4_writeback_write_end(file, mapping, pos,
+ len, copied, page, fsdata);
+ } else {
+ BUG();
+ }
}
- page_bufs = page_buffers(page);
- walk_page_buffers(handle, page_bufs, 0,
- PAGE_CACHE_SIZE, NULL, bget_one);
- ret = block_write_full_page(page, ext4_get_block, wbc);
+ trace_ext4_da_write_end(inode, pos, len, copied);
+ start = pos & (PAGE_CACHE_SIZE - 1);
+ end = start + copied - 1;
/*
- * The page can become unlocked at any point now, and
- * truncate can then come in and change things. So we
- * can't touch *page from now on. But *page_bufs is
- * safe due to elevated refcount.
+ * generic_write_end() will run mark_inode_dirty() if i_size
+ * changes. So let's piggyback the i_disksize mark_inode_dirty
+ * into that.
*/
- /*
- * And attach them to the current transaction. But only if
- * block_write_full_page() succeeded. Otherwise they are unmapped,
- * and generally junk.
- */
- if (ret == 0) {
- err = walk_page_buffers(handle, page_bufs, 0, PAGE_CACHE_SIZE,
- NULL, jbd2_journal_dirty_data_fn);
- if (!ret)
- ret = err;
+ new_i_size = pos + copied;
+ if (new_i_size > EXT4_I(inode)->i_disksize) {
+ if (ext4_da_should_update_i_disksize(page, end)) {
+ down_write(&EXT4_I(inode)->i_data_sem);
+ if (new_i_size > EXT4_I(inode)->i_disksize) {
+ /*
+ * Updating i_disksize when extending file
+ * without needing block allocation
+ */
+ if (ext4_should_order_data(inode))
+ ret = ext4_jbd2_file_inode(handle,
+ inode);
+
+ EXT4_I(inode)->i_disksize = new_i_size;
+ }
+ up_write(&EXT4_I(inode)->i_data_sem);
+ /* We need to mark inode dirty even if
+ * new_i_size is less that inode->i_size
+ * bu greater than i_disksize.(hint delalloc)
+ */
+ ext4_mark_inode_dirty(handle, inode);
+ }
}
- walk_page_buffers(handle, page_bufs, 0,
- PAGE_CACHE_SIZE, NULL, bput_one);
- err = ext4_journal_stop(handle);
+ ret2 = generic_write_end(file, mapping, pos, len, copied,
+ page, fsdata);
+ copied = ret2;
+ if (ret2 < 0)
+ ret = ret2;
+ ret2 = ext4_journal_stop(handle);
if (!ret)
- ret = err;
- return ret;
+ ret = ret2;
-out_fail:
- redirty_page_for_writepage(wbc, page);
- unlock_page(page);
- return ret;
+ return ret ? ret : copied;
}
-static int ext4_writeback_writepage(struct page *page,
- struct writeback_control *wbc)
+static void ext4_da_invalidatepage(struct page *page, unsigned long offset)
{
- struct inode *inode = page->mapping->host;
- handle_t *handle = NULL;
- int ret = 0;
- int err;
+ /*
+ * Drop reserved blocks
+ */
+ BUG_ON(!PageLocked(page));
+ if (!page_has_buffers(page))
+ goto out;
- if (ext4_journal_current_handle())
- goto out_fail;
+ ext4_da_page_release_reservation(page, offset);
- handle = ext4_journal_start(inode, ext4_writepage_trans_blocks(inode));
- if (IS_ERR(handle)) {
- ret = PTR_ERR(handle);
- goto out_fail;
- }
+out:
+ ext4_invalidatepage(page, offset);
- if (test_opt(inode->i_sb, NOBH) && ext4_should_writeback_data(inode))
- ret = nobh_writepage(page, ext4_get_block, wbc);
- else
- ret = block_write_full_page(page, ext4_get_block, wbc);
+ return;
+}
- err = ext4_journal_stop(handle);
- if (!ret)
- ret = err;
- return ret;
+/*
+ * Force all delayed allocation blocks to be allocated for a given inode.
+ */
+int ext4_alloc_da_blocks(struct inode *inode)
+{
+ trace_ext4_alloc_da_blocks(inode);
-out_fail:
- redirty_page_for_writepage(wbc, page);
- unlock_page(page);
- return ret;
+ if (!EXT4_I(inode)->i_reserved_data_blocks &&
+ !EXT4_I(inode)->i_reserved_meta_blocks)
+ return 0;
+
+ /*
+ * We do something simple for now. The filemap_flush() will
+ * also start triggering a write of the data blocks, which is
+ * not strictly speaking necessary (and for users of
+ * laptop_mode, not even desirable). However, to do otherwise
+ * would require replicating code paths in:
+ *
+ * ext4_da_writepages() ->
+ * write_cache_pages() ---> (via passed in callback function)
+ * __mpage_da_writepage() -->
+ * mpage_add_bh_to_extent()
+ * mpage_da_map_blocks()
+ *
+ * The problem is that write_cache_pages(), located in
+ * mm/page-writeback.c, marks pages clean in preparation for
+ * doing I/O, which is not desirable if we're not planning on
+ * doing I/O at all.
+ *
+ * We could call write_cache_pages(), and then redirty all of
+ * the pages by calling redirty_page_for_writeback() but that
+ * would be ugly in the extreme. So instead we would need to
+ * replicate parts of the code in the above functions,
+ * simplifying them becuase we wouldn't actually intend to
+ * write out the pages, but rather only collect contiguous
+ * logical block extents, call the multi-block allocator, and
+ * then update the buffer heads with the block allocations.
+ *
+ * For now, though, we'll cheat by calling filemap_flush(),
+ * which will map the blocks, and start the I/O, but not
+ * actually wait for the I/O to complete.
+ */
+ return filemap_flush(inode->i_mapping);
}
-static int ext4_journalled_writepage(struct page *page,
- struct writeback_control *wbc)
+/*
+ * bmap() is special. It gets used by applications such as lilo and by
+ * the swapper to find the on-disk block of a specific piece of data.
+ *
+ * Naturally, this is dangerous if the block concerned is still in the
+ * journal. If somebody makes a swapfile on an ext4 data-journaling
+ * filesystem and enables swap, then they may get a nasty shock when the
+ * data getting swapped to that swapfile suddenly gets overwritten by
+ * the original zero's written out previously to the journal and
+ * awaiting writeback in the kernel's buffer cache.
+ *
+ * So, if we see any bmap calls here on a modified, data-journaled file,
+ * take extra steps to flush any blocks which might be in the cache.
+ */
+static sector_t ext4_bmap(struct address_space *mapping, sector_t block)
{
- struct inode *inode = page->mapping->host;
- handle_t *handle = NULL;
- int ret = 0;
+ struct inode *inode = mapping->host;
+ journal_t *journal;
int err;
- if (ext4_journal_current_handle())
- goto no_write;
-
- handle = ext4_journal_start(inode, ext4_writepage_trans_blocks(inode));
- if (IS_ERR(handle)) {
- ret = PTR_ERR(handle);
- goto no_write;
- }
-
- if (!page_has_buffers(page) || PageChecked(page)) {
+ if (mapping_tagged(mapping, PAGECACHE_TAG_DIRTY) &&
+ test_opt(inode->i_sb, DELALLOC)) {
/*
- * It's mmapped pagecache. Add buffers and journal it. There
- * doesn't seem much point in redirtying the page here.
+ * With delalloc we want to sync the file
+ * so that we can make sure we allocate
+ * blocks for file
*/
- ClearPageChecked(page);
- ret = block_prepare_write(page, 0, PAGE_CACHE_SIZE,
- ext4_get_block);
- if (ret != 0) {
- ext4_journal_stop(handle);
- goto out_unlock;
- }
- ret = walk_page_buffers(handle, page_buffers(page), 0,
- PAGE_CACHE_SIZE, NULL, do_journal_get_write_access);
+ filemap_write_and_wait(mapping);
+ }
- err = walk_page_buffers(handle, page_buffers(page), 0,
- PAGE_CACHE_SIZE, NULL, write_end_fn);
- if (ret == 0)
- ret = err;
- EXT4_I(inode)->i_state |= EXT4_STATE_JDATA;
- unlock_page(page);
- } else {
+ if (EXT4_JOURNAL(inode) && EXT4_I(inode)->i_state & EXT4_STATE_JDATA) {
/*
- * It may be a page full of checkpoint-mode buffers. We don't
- * really know unless we go poke around in the buffer_heads.
- * But block_write_full_page will do the right thing.
+ * This is a REALLY heavyweight approach, but the use of
+ * bmap on dirty files is expected to be extremely rare:
+ * only if we run lilo or swapon on a freshly made file
+ * do we expect this to happen.
+ *
+ * (bmap requires CAP_SYS_RAWIO so this does not
+ * represent an unprivileged user DOS attack --- we'd be
+ * in trouble if mortal users could trigger this path at
+ * will.)
+ *
+ * NB. EXT4_STATE_JDATA is not set on files other than
+ * regular files. If somebody wants to bmap a directory
+ * or symlink and gets confused because the buffer
+ * hasn't yet been flushed to disk, they deserve
+ * everything they get.
*/
- ret = block_write_full_page(page, ext4_get_block, wbc);
+
+ EXT4_I(inode)->i_state &= ~EXT4_STATE_JDATA;
+ journal = EXT4_JOURNAL(inode);
+ jbd2_journal_lock_updates(journal);
+ err = jbd2_journal_flush(journal);
+ jbd2_journal_unlock_updates(journal);
+
+ if (err)
+ return 0;
}
- err = ext4_journal_stop(handle);
- if (!ret)
- ret = err;
-out:
- return ret;
-no_write:
- redirty_page_for_writepage(wbc, page);
-out_unlock:
- unlock_page(page);
- goto out;
+ return generic_block_bmap(mapping, block, ext4_get_block);
}
static int ext4_readpage(struct file *file, struct page *page)
if (offset == 0)
ClearPageChecked(page);
- jbd2_journal_invalidatepage(journal, page, offset);
+ if (journal)
+ jbd2_journal_invalidatepage(journal, page, offset);
+ else
+ block_invalidatepage(page, offset);
}
static int ext4_releasepage(struct page *page, gfp_t wait)
WARN_ON(PageChecked(page));
if (!page_has_buffers(page))
return 0;
- return jbd2_journal_try_to_free_buffers(journal, page, wait);
+ if (journal)
+ return jbd2_journal_try_to_free_buffers(journal, page, wait);
+ else
+ return try_to_free_buffers(page);
}
/*
+ * O_DIRECT for ext3 (or indirect map) based files
+ *
* If the O_DIRECT write will extend the file then add this inode to the
* orphan list. So recovery will truncate it back to the original size
* if the machine crashes during the write.
* crashes then stale disk data _may_ be exposed inside the file. But current
* VFS code falls back into buffered path in that case so we are safe.
*/
-static ssize_t ext4_direct_IO(int rw, struct kiocb *iocb,
- const struct iovec *iov, loff_t offset,
- unsigned long nr_segs)
+static ssize_t ext4_ind_direct_IO(int rw, struct kiocb *iocb,
+ const struct iovec *iov, loff_t offset,
+ unsigned long nr_segs)
{
struct file *file = iocb->ki_filp;
struct inode *inode = file->f_mapping->host;
ssize_t ret;
int orphan = 0;
size_t count = iov_length(iov, nr_segs);
+ int retries = 0;
if (rw == WRITE) {
loff_t final_size = offset + count;
}
}
+retry:
ret = blockdev_direct_IO(rw, iocb, inode, inode->i_sb->s_bdev, iov,
offset, nr_segs,
ext4_get_block, NULL);
+ if (ret == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries))
+ goto retry;
if (orphan) {
int err;
ext4_mark_inode_dirty(handle, inode);
}
}
- err = ext4_journal_stop(handle);
- if (ret == 0)
- ret = err;
+ err = ext4_journal_stop(handle);
+ if (ret == 0)
+ ret = err;
+ }
+out:
+ return ret;
+}
+
+/* Maximum number of blocks we map for direct IO at once. */
+
+static int ext4_get_block_dio_write(struct inode *inode, sector_t iblock,
+ struct buffer_head *bh_result, int create)
+{
+ handle_t *handle = NULL;
+ int ret = 0;
+ unsigned max_blocks = bh_result->b_size >> inode->i_blkbits;
+ int dio_credits;
+
+ ext4_debug("ext4_get_block_dio_write: inode %lu, create flag %d\n",
+ inode->i_ino, create);
+ /*
+ * DIO VFS code passes create = 0 flag for write to
+ * the middle of file. It does this to avoid block
+ * allocation for holes, to prevent expose stale data
+ * out when there is parallel buffered read (which does
+ * not hold the i_mutex lock) while direct IO write has
+ * not completed. DIO request on holes finally falls back
+ * to buffered IO for this reason.
+ *
+ * For ext4 extent based file, since we support fallocate,
+ * new allocated extent as uninitialized, for holes, we
+ * could fallocate blocks for holes, thus parallel
+ * buffered IO read will zero out the page when read on
+ * a hole while parallel DIO write to the hole has not completed.
+ *
+ * when we come here, we know it's a direct IO write to
+ * to the middle of file (<i_size)
+ * so it's safe to override the create flag from VFS.
+ */
+ create = EXT4_GET_BLOCKS_DIO_CREATE_EXT;
+
+ if (max_blocks > DIO_MAX_BLOCKS)
+ max_blocks = DIO_MAX_BLOCKS;
+ dio_credits = ext4_chunk_trans_blocks(inode, max_blocks);
+ handle = ext4_journal_start(inode, dio_credits);
+ if (IS_ERR(handle)) {
+ ret = PTR_ERR(handle);
+ goto out;
+ }
+ ret = ext4_get_blocks(handle, inode, iblock, max_blocks, bh_result,
+ create);
+ if (ret > 0) {
+ bh_result->b_size = (ret << inode->i_blkbits);
+ ret = 0;
+ }
+ ext4_journal_stop(handle);
+out:
+ return ret;
+}
+
+static void ext4_free_io_end(ext4_io_end_t *io)
+{
+ BUG_ON(!io);
+ iput(io->inode);
+ kfree(io);
+}
+static void dump_aio_dio_list(struct inode * inode)
+{
+#ifdef EXT4_DEBUG
+ struct list_head *cur, *before, *after;
+ ext4_io_end_t *io, *io0, *io1;
+
+ if (list_empty(&EXT4_I(inode)->i_aio_dio_complete_list)){
+ ext4_debug("inode %lu aio dio list is empty\n", inode->i_ino);
+ return;
+ }
+
+ ext4_debug("Dump inode %lu aio_dio_completed_IO list \n", inode->i_ino);
+ list_for_each_entry(io, &EXT4_I(inode)->i_aio_dio_complete_list, list){
+ cur = &io->list;
+ before = cur->prev;
+ io0 = container_of(before, ext4_io_end_t, list);
+ after = cur->next;
+ io1 = container_of(after, ext4_io_end_t, list);
+
+ ext4_debug("io 0x%p from inode %lu,prev 0x%p,next 0x%p\n",
+ io, inode->i_ino, io0, io1);
+ }
+#endif
+}
+
+/*
+ * check a range of space and convert unwritten extents to written.
+ */
+static int ext4_end_aio_dio_nolock(ext4_io_end_t *io)
+{
+ struct inode *inode = io->inode;
+ loff_t offset = io->offset;
+ size_t size = io->size;
+ int ret = 0;
+
+ ext4_debug("end_aio_dio_onlock: io 0x%p from inode %lu,list->next 0x%p,"
+ "list->prev 0x%p\n",
+ io, inode->i_ino, io->list.next, io->list.prev);
+
+ if (list_empty(&io->list))
+ return ret;
+
+ if (io->flag != DIO_AIO_UNWRITTEN)
+ return ret;
+
+ if (offset + size <= i_size_read(inode))
+ ret = ext4_convert_unwritten_extents(inode, offset, size);
+
+ if (ret < 0) {
+ printk(KERN_EMERG "%s: failed to convert unwritten"
+ "extents to written extents, error is %d"
+ " io is still on inode %lu aio dio list\n",
+ __func__, ret, inode->i_ino);
+ return ret;
+ }
+
+ /* clear the DIO AIO unwritten flag */
+ io->flag = 0;
+ return ret;
+}
+/*
+ * work on completed aio dio IO, to convert unwritten extents to extents
+ */
+static void ext4_end_aio_dio_work(struct work_struct *work)
+{
+ ext4_io_end_t *io = container_of(work, ext4_io_end_t, work);
+ struct inode *inode = io->inode;
+ int ret = 0;
+
+ mutex_lock(&inode->i_mutex);
+ ret = ext4_end_aio_dio_nolock(io);
+ if (ret >= 0) {
+ if (!list_empty(&io->list))
+ list_del_init(&io->list);
+ ext4_free_io_end(io);
+ }
+ mutex_unlock(&inode->i_mutex);
+}
+/*
+ * This function is called from ext4_sync_file().
+ *
+ * When AIO DIO IO is completed, the work to convert unwritten
+ * extents to written is queued on workqueue but may not get immediately
+ * scheduled. When fsync is called, we need to ensure the
+ * conversion is complete before fsync returns.
+ * The inode keeps track of a list of completed AIO from DIO path
+ * that might needs to do the conversion. This function walks through
+ * the list and convert the related unwritten extents to written.
+ */
+int flush_aio_dio_completed_IO(struct inode *inode)
+{
+ ext4_io_end_t *io;
+ int ret = 0;
+ int ret2 = 0;
+
+ if (list_empty(&EXT4_I(inode)->i_aio_dio_complete_list))
+ return ret;
+
+ dump_aio_dio_list(inode);
+ while (!list_empty(&EXT4_I(inode)->i_aio_dio_complete_list)){
+ io = list_entry(EXT4_I(inode)->i_aio_dio_complete_list.next,
+ ext4_io_end_t, list);
+ /*
+ * Calling ext4_end_aio_dio_nolock() to convert completed
+ * IO to written.
+ *
+ * When ext4_sync_file() is called, run_queue() may already
+ * about to flush the work corresponding to this io structure.
+ * It will be upset if it founds the io structure related
+ * to the work-to-be schedule is freed.
+ *
+ * Thus we need to keep the io structure still valid here after
+ * convertion finished. The io structure has a flag to
+ * avoid double converting from both fsync and background work
+ * queue work.
+ */
+ ret = ext4_end_aio_dio_nolock(io);
+ if (ret < 0)
+ ret2 = ret;
+ else
+ list_del_init(&io->list);
+ }
+ return (ret2 < 0) ? ret2 : 0;
+}
+
+static ext4_io_end_t *ext4_init_io_end (struct inode *inode)
+{
+ ext4_io_end_t *io = NULL;
+
+ io = kmalloc(sizeof(*io), GFP_NOFS);
+
+ if (io) {
+ igrab(inode);
+ io->inode = inode;
+ io->flag = 0;
+ io->offset = 0;
+ io->size = 0;
+ io->error = 0;
+ INIT_WORK(&io->work, ext4_end_aio_dio_work);
+ INIT_LIST_HEAD(&io->list);
+ }
+
+ return io;
+}
+
+static void ext4_end_io_dio(struct kiocb *iocb, loff_t offset,
+ ssize_t size, void *private)
+{
+ ext4_io_end_t *io_end = iocb->private;
+ struct workqueue_struct *wq;
+
+ ext_debug("ext4_end_io_dio(): io_end 0x%p"
+ "for inode %lu, iocb 0x%p, offset %llu, size %llu\n",
+ iocb->private, io_end->inode->i_ino, iocb, offset,
+ size);
+ /* if not async direct IO or dio with 0 bytes write, just return */
+ if (!io_end || !size)
+ return;
+
+ /* if not aio dio with unwritten extents, just free io and return */
+ if (io_end->flag != DIO_AIO_UNWRITTEN){
+ ext4_free_io_end(io_end);
+ iocb->private = NULL;
+ return;
+ }
+
+ io_end->offset = offset;
+ io_end->size = size;
+ wq = EXT4_SB(io_end->inode->i_sb)->dio_unwritten_wq;
+
+ /* queue the work to convert unwritten extents to written */
+ queue_work(wq, &io_end->work);
+
+ /* Add the io_end to per-inode completed aio dio list*/
+ list_add_tail(&io_end->list,
+ &EXT4_I(io_end->inode)->i_aio_dio_complete_list);
+ iocb->private = NULL;
+}
+/*
+ * For ext4 extent files, ext4 will do direct-io write to holes,
+ * preallocated extents, and those write extend the file, no need to
+ * fall back to buffered IO.
+ *
+ * For holes, we fallocate those blocks, mark them as unintialized
+ * If those blocks were preallocated, we mark sure they are splited, but
+ * still keep the range to write as unintialized.
+ *
+ * The unwrritten extents will be converted to written when DIO is completed.
+ * For async direct IO, since the IO may still pending when return, we
+ * set up an end_io call back function, which will do the convertion
+ * when async direct IO completed.
+ *
+ * If the O_DIRECT write will extend the file then add this inode to the
+ * orphan list. So recovery will truncate it back to the original size
+ * if the machine crashes during the write.
+ *
+ */
+static ssize_t ext4_ext_direct_IO(int rw, struct kiocb *iocb,
+ const struct iovec *iov, loff_t offset,
+ unsigned long nr_segs)
+{
+ struct file *file = iocb->ki_filp;
+ struct inode *inode = file->f_mapping->host;
+ ssize_t ret;
+ size_t count = iov_length(iov, nr_segs);
+
+ loff_t final_size = offset + count;
+ if (rw == WRITE && final_size <= inode->i_size) {
+ /*
+ * We could direct write to holes and fallocate.
+ *
+ * Allocated blocks to fill the hole are marked as uninitialized
+ * to prevent paralel buffered read to expose the stale data
+ * before DIO complete the data IO.
+ *
+ * As to previously fallocated extents, ext4 get_block
+ * will just simply mark the buffer mapped but still
+ * keep the extents uninitialized.
+ *
+ * for non AIO case, we will convert those unwritten extents
+ * to written after return back from blockdev_direct_IO.
+ *
+ * for async DIO, the conversion needs to be defered when
+ * the IO is completed. The ext4 end_io callback function
+ * will be called to take care of the conversion work.
+ * Here for async case, we allocate an io_end structure to
+ * hook to the iocb.
+ */
+ iocb->private = NULL;
+ EXT4_I(inode)->cur_aio_dio = NULL;
+ if (!is_sync_kiocb(iocb)) {
+ iocb->private = ext4_init_io_end(inode);
+ if (!iocb->private)
+ return -ENOMEM;
+ /*
+ * we save the io structure for current async
+ * direct IO, so that later ext4_get_blocks()
+ * could flag the io structure whether there
+ * is a unwritten extents needs to be converted
+ * when IO is completed.
+ */
+ EXT4_I(inode)->cur_aio_dio = iocb->private;
+ }
+
+ ret = blockdev_direct_IO(rw, iocb, inode,
+ inode->i_sb->s_bdev, iov,
+ offset, nr_segs,
+ ext4_get_block_dio_write,
+ ext4_end_io_dio);
+ if (iocb->private)
+ EXT4_I(inode)->cur_aio_dio = NULL;
+ /*
+ * The io_end structure takes a reference to the inode,
+ * that structure needs to be destroyed and the
+ * reference to the inode need to be dropped, when IO is
+ * complete, even with 0 byte write, or failed.
+ *
+ * In the successful AIO DIO case, the io_end structure will be
+ * desctroyed and the reference to the inode will be dropped
+ * after the end_io call back function is called.
+ *
+ * In the case there is 0 byte write, or error case, since
+ * VFS direct IO won't invoke the end_io call back function,
+ * we need to free the end_io structure here.
+ */
+ if (ret != -EIOCBQUEUED && ret <= 0 && iocb->private) {
+ ext4_free_io_end(iocb->private);
+ iocb->private = NULL;
+ } else if (ret > 0)
+ /*
+ * for non AIO case, since the IO is already
+ * completed, we could do the convertion right here
+ */
+ ret = ext4_convert_unwritten_extents(inode,
+ offset, ret);
+ return ret;
}
-out:
- return ret;
+
+ /* for write the the end of file case, we fall back to old way */
+ return ext4_ind_direct_IO(rw, iocb, iov, offset, nr_segs);
+}
+
+static ssize_t ext4_direct_IO(int rw, struct kiocb *iocb,
+ const struct iovec *iov, loff_t offset,
+ unsigned long nr_segs)
+{
+ struct file *file = iocb->ki_filp;
+ struct inode *inode = file->f_mapping->host;
+
+ if (EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL)
+ return ext4_ext_direct_IO(rw, iocb, iov, offset, nr_segs);
+
+ return ext4_ind_direct_IO(rw, iocb, iov, offset, nr_segs);
}
/*
}
static const struct address_space_operations ext4_ordered_aops = {
- .readpage = ext4_readpage,
- .readpages = ext4_readpages,
- .writepage = ext4_ordered_writepage,
- .sync_page = block_sync_page,
- .write_begin = ext4_write_begin,
- .write_end = ext4_ordered_write_end,
- .bmap = ext4_bmap,
- .invalidatepage = ext4_invalidatepage,
- .releasepage = ext4_releasepage,
- .direct_IO = ext4_direct_IO,
- .migratepage = buffer_migrate_page,
+ .readpage = ext4_readpage,
+ .readpages = ext4_readpages,
+ .writepage = ext4_writepage,
+ .sync_page = block_sync_page,
+ .write_begin = ext4_write_begin,
+ .write_end = ext4_ordered_write_end,
+ .bmap = ext4_bmap,
+ .invalidatepage = ext4_invalidatepage,
+ .releasepage = ext4_releasepage,
+ .direct_IO = ext4_direct_IO,
+ .migratepage = buffer_migrate_page,
+ .is_partially_uptodate = block_is_partially_uptodate,
+ .error_remove_page = generic_error_remove_page,
};
static const struct address_space_operations ext4_writeback_aops = {
- .readpage = ext4_readpage,
- .readpages = ext4_readpages,
- .writepage = ext4_writeback_writepage,
- .sync_page = block_sync_page,
- .write_begin = ext4_write_begin,
- .write_end = ext4_writeback_write_end,
- .bmap = ext4_bmap,
- .invalidatepage = ext4_invalidatepage,
- .releasepage = ext4_releasepage,
- .direct_IO = ext4_direct_IO,
- .migratepage = buffer_migrate_page,
+ .readpage = ext4_readpage,
+ .readpages = ext4_readpages,
+ .writepage = ext4_writepage,
+ .sync_page = block_sync_page,
+ .write_begin = ext4_write_begin,
+ .write_end = ext4_writeback_write_end,
+ .bmap = ext4_bmap,
+ .invalidatepage = ext4_invalidatepage,
+ .releasepage = ext4_releasepage,
+ .direct_IO = ext4_direct_IO,
+ .migratepage = buffer_migrate_page,
+ .is_partially_uptodate = block_is_partially_uptodate,
+ .error_remove_page = generic_error_remove_page,
};
static const struct address_space_operations ext4_journalled_aops = {
- .readpage = ext4_readpage,
- .readpages = ext4_readpages,
- .writepage = ext4_journalled_writepage,
- .sync_page = block_sync_page,
- .write_begin = ext4_write_begin,
- .write_end = ext4_journalled_write_end,
- .set_page_dirty = ext4_journalled_set_page_dirty,
- .bmap = ext4_bmap,
- .invalidatepage = ext4_invalidatepage,
- .releasepage = ext4_releasepage,
+ .readpage = ext4_readpage,
+ .readpages = ext4_readpages,
+ .writepage = ext4_writepage,
+ .sync_page = block_sync_page,
+ .write_begin = ext4_write_begin,
+ .write_end = ext4_journalled_write_end,
+ .set_page_dirty = ext4_journalled_set_page_dirty,
+ .bmap = ext4_bmap,
+ .invalidatepage = ext4_invalidatepage,
+ .releasepage = ext4_releasepage,
+ .is_partially_uptodate = block_is_partially_uptodate,
+ .error_remove_page = generic_error_remove_page,
+};
+
+static const struct address_space_operations ext4_da_aops = {
+ .readpage = ext4_readpage,
+ .readpages = ext4_readpages,
+ .writepage = ext4_writepage,
+ .writepages = ext4_da_writepages,
+ .sync_page = block_sync_page,
+ .write_begin = ext4_da_write_begin,
+ .write_end = ext4_da_write_end,
+ .bmap = ext4_bmap,
+ .invalidatepage = ext4_da_invalidatepage,
+ .releasepage = ext4_releasepage,
+ .direct_IO = ext4_direct_IO,
+ .migratepage = buffer_migrate_page,
+ .is_partially_uptodate = block_is_partially_uptodate,
+ .error_remove_page = generic_error_remove_page,
};
void ext4_set_aops(struct inode *inode)
{
- if (ext4_should_order_data(inode))
+ if (ext4_should_order_data(inode) &&
+ test_opt(inode->i_sb, DELALLOC))
+ inode->i_mapping->a_ops = &ext4_da_aops;
+ else if (ext4_should_order_data(inode))
inode->i_mapping->a_ops = &ext4_ordered_aops;
+ else if (ext4_should_writeback_data(inode) &&
+ test_opt(inode->i_sb, DELALLOC))
+ inode->i_mapping->a_ops = &ext4_da_aops;
else if (ext4_should_writeback_data(inode))
inode->i_mapping->a_ops = &ext4_writeback_aops;
else
* This required during truncate. We need to physically zero the tail end
* of that block so it doesn't yield old data if the file is later grown.
*/
-int ext4_block_truncate_page(handle_t *handle, struct page *page,
+int ext4_block_truncate_page(handle_t *handle,
struct address_space *mapping, loff_t from)
{
ext4_fsblk_t index = from >> PAGE_CACHE_SHIFT;
ext4_lblk_t iblock;
struct inode *inode = mapping->host;
struct buffer_head *bh;
+ struct page *page;
int err = 0;
+ page = find_or_create_page(mapping, from >> PAGE_CACHE_SHIFT,
+ mapping_gfp_mask(mapping) & ~__GFP_FS);
+ if (!page)
+ return -EINVAL;
+
blocksize = inode->i_sb->s_blocksize;
length = blocksize - (offset & (blocksize - 1));
iblock = index << (PAGE_CACHE_SHIFT - inode->i_sb->s_blocksize_bits);
err = 0;
if (ext4_should_journal_data(inode)) {
- err = ext4_journal_dirty_metadata(handle, bh);
+ err = ext4_handle_dirty_metadata(handle, inode, bh);
} else {
if (ext4_should_order_data(inode))
- err = ext4_journal_dirty_data(handle, bh);
+ err = ext4_jbd2_file_inode(handle, inode);
mark_buffer_dirty(bh);
}
* (no partially truncated stuff there). */
static Indirect *ext4_find_shared(struct inode *inode, int depth,
- ext4_lblk_t offsets[4], Indirect chain[4], __le32 *top)
+ ext4_lblk_t offsets[4], Indirect chain[4],
+ __le32 *top)
{
Indirect *partial, *p;
int k, err;
*top = 0;
- /* Make k index the deepest non-null offest + 1 */
+ /* Make k index the deepest non-null offset + 1 */
for (k = depth; k > 1 && !offsets[k-1]; k--)
;
partial = ext4_get_branch(inode, k, offsets, chain, &err);
if (!partial->key && *partial->p)
/* Writer: end */
goto no_top;
- for (p=partial; p>chain && all_zeroes((__le32*)p->bh->b_data,p->p); p--)
+ for (p = partial; (p > chain) && all_zeroes((__le32 *) p->bh->b_data, p->p); p--)
;
/*
* OK, we've found the last block that must survive. The rest of our
}
/* Writer: end */
- while(partial > p) {
+ while (partial > p) {
brelse(partial->bh);
partial--;
}
* than `count' because there can be holes in there.
*/
static void ext4_clear_blocks(handle_t *handle, struct inode *inode,
- struct buffer_head *bh, ext4_fsblk_t block_to_free,
- unsigned long count, __le32 *first, __le32 *last)
+ struct buffer_head *bh,
+ ext4_fsblk_t block_to_free,
+ unsigned long count, __le32 *first,
+ __le32 *last)
{
__le32 *p;
if (try_to_extend_transaction(handle, inode)) {
if (bh) {
- BUFFER_TRACE(bh, "call ext4_journal_dirty_metadata");
- ext4_journal_dirty_metadata(handle, bh);
+ BUFFER_TRACE(bh, "call ext4_handle_dirty_metadata");
+ ext4_handle_dirty_metadata(handle, inode, bh);
}
ext4_mark_inode_dirty(handle, inode);
- ext4_journal_test_restart(handle, inode);
+ ext4_truncate_restart_trans(handle, inode,
+ blocks_for_truncate(inode));
if (bh) {
BUFFER_TRACE(bh, "retaking write access");
ext4_journal_get_write_access(handle, bh);
}
/*
- * Any buffers which are on the journal will be in memory. We find
- * them on the hash table so jbd2_journal_revoke() will run jbd2_journal_forget()
- * on them. We've already detached each block from the file, so
- * bforget() in jbd2_journal_forget() should be safe.
+ * Any buffers which are on the journal will be in memory. We
+ * find them on the hash table so jbd2_journal_revoke() will
+ * run jbd2_journal_forget() on them. We've already detached
+ * each block from the file, so bforget() in
+ * jbd2_journal_forget() should be safe.
*
* AKPM: turn on bforget in jbd2_journal_forget()!!!
*/
count, block_to_free_p, p);
if (this_bh) {
- BUFFER_TRACE(this_bh, "call ext4_journal_dirty_metadata");
- ext4_journal_dirty_metadata(handle, this_bh);
+ BUFFER_TRACE(this_bh, "call ext4_handle_dirty_metadata");
+
+ /*
+ * The buffer head should have an attached journal head at this
+ * point. However, if the data is corrupted and an indirect
+ * block pointed to itself, it would have been detached when
+ * the block was cleared. Check for this instead of OOPSing.
+ */
+ if ((EXT4_JOURNAL(inode) == NULL) || bh2jh(this_bh))
+ ext4_handle_dirty_metadata(handle, inode, this_bh);
+ else
+ ext4_error(inode->i_sb, __func__,
+ "circular indirect block detected, "
+ "inode=%lu, block=%llu",
+ inode->i_ino,
+ (unsigned long long) this_bh->b_blocknr);
}
}
ext4_fsblk_t nr;
__le32 *p;
- if (is_handle_aborted(handle))
+ if (ext4_handle_is_aborted(handle))
return;
if (depth--) {
/* This zaps the entire block. Bottom up. */
BUFFER_TRACE(bh, "free child branches");
ext4_free_branches(handle, inode, bh,
- (__le32*)bh->b_data,
- (__le32*)bh->b_data + addr_per_block,
- depth);
+ (__le32 *) bh->b_data,
+ (__le32 *) bh->b_data + addr_per_block,
+ depth);
/*
* We've probably journalled the indirect block several
* will merely complain about releasing a free block,
* rather than leaking blocks.
*/
- if (is_handle_aborted(handle))
+ if (ext4_handle_is_aborted(handle))
return;
if (try_to_extend_transaction(handle, inode)) {
ext4_mark_inode_dirty(handle, inode);
- ext4_journal_test_restart(handle, inode);
+ ext4_truncate_restart_trans(handle, inode,
+ blocks_for_truncate(inode));
}
ext4_free_blocks(handle, inode, nr, 1, 1);
parent_bh)){
*p = 0;
BUFFER_TRACE(parent_bh,
- "call ext4_journal_dirty_metadata");
- ext4_journal_dirty_metadata(handle,
- parent_bh);
+ "call ext4_handle_dirty_metadata");
+ ext4_handle_dirty_metadata(handle,
+ inode,
+ parent_bh);
}
}
}
}
}
+int ext4_can_truncate(struct inode *inode)
+{
+ if (IS_APPEND(inode) || IS_IMMUTABLE(inode))
+ return 0;
+ if (S_ISREG(inode->i_mode))
+ return 1;
+ if (S_ISDIR(inode->i_mode))
+ return 1;
+ if (S_ISLNK(inode->i_mode))
+ return !ext4_inode_is_fast_symlink(inode);
+ return 0;
+}
+
/*
* ext4_truncate()
*
int n;
ext4_lblk_t last_block;
unsigned blocksize = inode->i_sb->s_blocksize;
- struct page *page;
- if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
- S_ISLNK(inode->i_mode)))
- return;
- if (ext4_inode_is_fast_symlink(inode))
- return;
- if (IS_APPEND(inode) || IS_IMMUTABLE(inode))
+ if (!ext4_can_truncate(inode))
return;
- /*
- * We have to lock the EOF page here, because lock_page() nests
- * outside jbd2_journal_start().
- */
- if ((inode->i_size & (blocksize - 1)) == 0) {
- /* Block boundary? Nothing to do */
- page = NULL;
- } else {
- page = grab_cache_page(mapping,
- inode->i_size >> PAGE_CACHE_SHIFT);
- if (!page)
- return;
- }
+ if (inode->i_size == 0 && !test_opt(inode->i_sb, NO_AUTO_DA_ALLOC))
+ ei->i_state |= EXT4_STATE_DA_ALLOC_CLOSE;
if (EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL) {
- ext4_ext_truncate(inode, page);
+ ext4_ext_truncate(inode);
return;
}
handle = start_transaction(inode);
- if (IS_ERR(handle)) {
- if (page) {
- clear_highpage(page);
- flush_dcache_page(page);
- unlock_page(page);
- page_cache_release(page);
- }
+ if (IS_ERR(handle))
return; /* AKPM: return what? */
- }
last_block = (inode->i_size + blocksize-1)
>> EXT4_BLOCK_SIZE_BITS(inode->i_sb);
- if (page)
- ext4_block_truncate_page(handle, page, mapping, inode->i_size);
+ if (inode->i_size & (blocksize - 1))
+ if (ext4_block_truncate_page(handle, mapping, inode->i_size))
+ goto out_stop;
n = ext4_block_to_path(inode, last_block, offsets, NULL);
if (n == 0)
goto out_stop;
/*
+ * From here we block out all ext4_get_block() callers who want to
+ * modify the block allocation tree.
+ */
+ down_write(&ei->i_data_sem);
+
+ ext4_discard_preallocations(inode);
+
+ /*
* The orphan list entry will now protect us from any crash which
* occurs before the truncate completes, so it is now safe to propagate
* the new, shorter inode size (held for now in i_size) into the
*/
ei->i_disksize = inode->i_size;
- /*
- * From here we block out all ext4_get_block() callers who want to
- * modify the block allocation tree.
- */
- down_write(&ei->i_data_sem);
-
if (n == 1) { /* direct blocks */
ext4_free_data(handle, inode, NULL, i_data+offsets[0],
i_data + EXT4_NDIR_BLOCKS);
(__le32*)partial->bh->b_data+addr_per_block,
(chain+n-1) - partial);
BUFFER_TRACE(partial->bh, "call brelse");
- brelse (partial->bh);
+ brelse(partial->bh);
partial--;
}
do_indirects:
;
}
- ext4_discard_reservation(inode);
-
up_write(&ei->i_data_sem);
inode->i_mtime = inode->i_ctime = ext4_current_time(inode);
ext4_mark_inode_dirty(handle, inode);
* synchronous
*/
if (IS_SYNC(inode))
- handle->h_sync = 1;
+ ext4_handle_sync(handle);
out_stop:
/*
* If this was a simple ftruncate(), and the file will remain alive
ext4_journal_stop(handle);
}
-static ext4_fsblk_t ext4_get_inode_block(struct super_block *sb,
- unsigned long ino, struct ext4_iloc *iloc)
-{
- unsigned long desc, group_desc;
- ext4_group_t block_group;
- unsigned long offset;
- ext4_fsblk_t block;
- struct buffer_head *bh;
- struct ext4_group_desc * gdp;
-
- if (!ext4_valid_inum(sb, ino)) {
- /*
- * This error is already checked for in namei.c unless we are
- * looking at an NFS filehandle, in which case no error
- * report is needed
- */
- return 0;
- }
-
- block_group = (ino - 1) / EXT4_INODES_PER_GROUP(sb);
- if (block_group >= EXT4_SB(sb)->s_groups_count) {
- ext4_error(sb,"ext4_get_inode_block","group >= groups count");
- return 0;
- }
- smp_rmb();
- group_desc = block_group >> EXT4_DESC_PER_BLOCK_BITS(sb);
- desc = block_group & (EXT4_DESC_PER_BLOCK(sb) - 1);
- bh = EXT4_SB(sb)->s_group_desc[group_desc];
- if (!bh) {
- ext4_error (sb, "ext4_get_inode_block",
- "Descriptor not loaded");
- return 0;
- }
-
- gdp = (struct ext4_group_desc *)((__u8 *)bh->b_data +
- desc * EXT4_DESC_SIZE(sb));
- /*
- * Figure out the offset within the block group inode table
- */
- offset = ((ino - 1) % EXT4_INODES_PER_GROUP(sb)) *
- EXT4_INODE_SIZE(sb);
- block = ext4_inode_table(sb, gdp) +
- (offset >> EXT4_BLOCK_SIZE_BITS(sb));
-
- iloc->block_group = block_group;
- iloc->offset = offset & (EXT4_BLOCK_SIZE(sb) - 1);
- return block;
-}
-
/*
* ext4_get_inode_loc returns with an extra refcount against the inode's
* underlying buffer_head on success. If 'in_mem' is true, we have all
static int __ext4_get_inode_loc(struct inode *inode,
struct ext4_iloc *iloc, int in_mem)
{
- ext4_fsblk_t block;
- struct buffer_head *bh;
+ struct ext4_group_desc *gdp;
+ struct buffer_head *bh;
+ struct super_block *sb = inode->i_sb;
+ ext4_fsblk_t block;
+ int inodes_per_block, inode_offset;
+
+ iloc->bh = NULL;
+ if (!ext4_valid_inum(sb, inode->i_ino))
+ return -EIO;
- block = ext4_get_inode_block(inode->i_sb, inode->i_ino, iloc);
- if (!block)
+ iloc->block_group = (inode->i_ino - 1) / EXT4_INODES_PER_GROUP(sb);
+ gdp = ext4_get_group_desc(sb, iloc->block_group, NULL);
+ if (!gdp)
return -EIO;
- bh = sb_getblk(inode->i_sb, block);
+ /*
+ * Figure out the offset within the block group inode table
+ */
+ inodes_per_block = (EXT4_BLOCK_SIZE(sb) / EXT4_INODE_SIZE(sb));
+ inode_offset = ((inode->i_ino - 1) %
+ EXT4_INODES_PER_GROUP(sb));
+ block = ext4_inode_table(sb, gdp) + (inode_offset / inodes_per_block);
+ iloc->offset = (inode_offset % inodes_per_block) * EXT4_INODE_SIZE(sb);
+
+ bh = sb_getblk(sb, block);
if (!bh) {
- ext4_error (inode->i_sb, "ext4_get_inode_loc",
- "unable to read inode block - "
- "inode=%lu, block=%llu",
- inode->i_ino, block);
+ ext4_error(sb, "ext4_get_inode_loc", "unable to read "
+ "inode block - inode=%lu, block=%llu",
+ inode->i_ino, block);
return -EIO;
}
if (!buffer_uptodate(bh)) {
lock_buffer(bh);
+
+ /*
+ * If the buffer has the write error flag, we have failed
+ * to write out another inode in the same block. In this
+ * case, we don't have to read the block because we may
+ * read the old inode data successfully.
+ */
+ if (buffer_write_io_error(bh) && !buffer_uptodate(bh))
+ set_buffer_uptodate(bh);
+
if (buffer_uptodate(bh)) {
/* someone brought it uptodate while we waited */
unlock_buffer(bh);
*/
if (in_mem) {
struct buffer_head *bitmap_bh;
- struct ext4_group_desc *desc;
- int inodes_per_buffer;
- int inode_offset, i;
- ext4_group_t block_group;
- int start;
-
- block_group = (inode->i_ino - 1) /
- EXT4_INODES_PER_GROUP(inode->i_sb);
- inodes_per_buffer = bh->b_size /
- EXT4_INODE_SIZE(inode->i_sb);
- inode_offset = ((inode->i_ino - 1) %
- EXT4_INODES_PER_GROUP(inode->i_sb));
- start = inode_offset & ~(inodes_per_buffer - 1);
+ int i, start;
- /* Is the inode bitmap in cache? */
- desc = ext4_get_group_desc(inode->i_sb,
- block_group, NULL);
- if (!desc)
- goto make_io;
+ start = inode_offset & ~(inodes_per_block - 1);
- bitmap_bh = sb_getblk(inode->i_sb,
- ext4_inode_bitmap(inode->i_sb, desc));
+ /* Is the inode bitmap in cache? */
+ bitmap_bh = sb_getblk(sb, ext4_inode_bitmap(sb, gdp));
if (!bitmap_bh)
goto make_io;
brelse(bitmap_bh);
goto make_io;
}
- for (i = start; i < start + inodes_per_buffer; i++) {
+ for (i = start; i < start + inodes_per_block; i++) {
if (i == inode_offset)
continue;
if (ext4_test_bit(i, bitmap_bh->b_data))
break;
}
brelse(bitmap_bh);
- if (i == start + inodes_per_buffer) {
+ if (i == start + inodes_per_block) {
/* all other inodes are free, so skip I/O */
memset(bh->b_data, 0, bh->b_size);
set_buffer_uptodate(bh);
make_io:
/*
+ * If we need to do any I/O, try to pre-readahead extra
+ * blocks from the inode table.
+ */
+ if (EXT4_SB(sb)->s_inode_readahead_blks) {
+ ext4_fsblk_t b, end, table;
+ unsigned num;
+
+ table = ext4_inode_table(sb, gdp);
+ /* s_inode_readahead_blks is always a power of 2 */
+ b = block & ~(EXT4_SB(sb)->s_inode_readahead_blks-1);
+ if (table > b)
+ b = table;
+ end = b + EXT4_SB(sb)->s_inode_readahead_blks;
+ num = EXT4_INODES_PER_GROUP(sb);
+ if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
+ EXT4_FEATURE_RO_COMPAT_GDT_CSUM))
+ num -= ext4_itable_unused_count(sb, gdp);
+ table += num / inodes_per_block;
+ if (end > table)
+ end = table;
+ while (b <= end)
+ sb_breadahead(sb, b++);
+ }
+
+ /*
* There are other valid inodes in the buffer, this inode
* has in-inode xattrs, or we don't have this inode in memory.
* Read the block from disk.
submit_bh(READ_META, bh);
wait_on_buffer(bh);
if (!buffer_uptodate(bh)) {
- ext4_error(inode->i_sb, "ext4_get_inode_loc",
- "unable to read inode block - "
- "inode=%lu, block=%llu",
- inode->i_ino, block);
+ ext4_error(sb, __func__,
+ "unable to read inode block - inode=%lu, "
+ "block=%llu", inode->i_ino, block);
brelse(bh);
return -EIO;
}
if (flags & S_DIRSYNC)
ei->i_flags |= EXT4_DIRSYNC_FL;
}
+
static blkcnt_t ext4_inode_blocks(struct ext4_inode *raw_inode,
- struct ext4_inode_info *ei)
+ struct ext4_inode_info *ei)
{
blkcnt_t i_blocks ;
struct inode *inode = &(ei->vfs_inode);
return inode;
ei = EXT4_I(inode);
-#ifdef CONFIG_EXT4DEV_FS_POSIX_ACL
- ei->i_acl = EXT4_ACL_NOT_CACHED;
- ei->i_default_acl = EXT4_ACL_NOT_CACHED;
-#endif
- ei->i_block_alloc_info = NULL;
ret = __ext4_get_inode_loc(inode, &iloc, 0);
if (ret < 0)
inode->i_mode = le16_to_cpu(raw_inode->i_mode);
inode->i_uid = (uid_t)le16_to_cpu(raw_inode->i_uid_low);
inode->i_gid = (gid_t)le16_to_cpu(raw_inode->i_gid_low);
- if(!(test_opt (inode->i_sb, NO_UID32))) {
+ if (!(test_opt(inode->i_sb, NO_UID32))) {
inode->i_uid |= le16_to_cpu(raw_inode->i_uid_high) << 16;
inode->i_gid |= le16_to_cpu(raw_inode->i_gid_high) << 16;
}
if (inode->i_mode == 0 ||
!(EXT4_SB(inode->i_sb)->s_mount_state & EXT4_ORPHAN_FS)) {
/* this inode is deleted */
- brelse (bh);
+ brelse(bh);
ret = -ESTALE;
goto bad_inode;
}
ei->i_flags = le32_to_cpu(raw_inode->i_flags);
inode->i_blocks = ext4_inode_blocks(raw_inode, ei);
ei->i_file_acl = le32_to_cpu(raw_inode->i_file_acl_lo);
- if (EXT4_SB(inode->i_sb)->s_es->s_creator_os !=
- cpu_to_le32(EXT4_OS_HURD)) {
+ if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_64BIT))
ei->i_file_acl |=
((__u64)le16_to_cpu(raw_inode->i_file_acl_high)) << 32;
- }
inode->i_size = ext4_isize(raw_inode);
ei->i_disksize = inode->i_size;
inode->i_generation = le32_to_cpu(raw_inode->i_generation);
ei->i_block_group = iloc.block_group;
+ ei->i_last_alloc_group = ~0;
/*
* NOTE! The in-memory inode i_data array is in little-endian order
* even on big-endian machines: we do NOT byteswap the block numbers!
ei->i_extra_isize = le16_to_cpu(raw_inode->i_extra_isize);
if (EXT4_GOOD_OLD_INODE_SIZE + ei->i_extra_isize >
EXT4_INODE_SIZE(inode->i_sb)) {
- brelse (bh);
+ brelse(bh);
ret = -EIO;
goto bad_inode;
}
EXT4_GOOD_OLD_INODE_SIZE +
ei->i_extra_isize;
if (*magic == cpu_to_le32(EXT4_XATTR_MAGIC))
- ei->i_state |= EXT4_STATE_XATTR;
+ ei->i_state |= EXT4_STATE_XATTR;
}
} else
ei->i_extra_isize = 0;
(__u64)(le32_to_cpu(raw_inode->i_version_hi)) << 32;
}
+ ret = 0;
+ if (ei->i_file_acl &&
+ ((ei->i_file_acl <
+ (le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block) +
+ EXT4_SB(sb)->s_gdb_count)) ||
+ (ei->i_file_acl >= ext4_blocks_count(EXT4_SB(sb)->s_es)))) {
+ ext4_error(sb, __func__,
+ "bad extended attribute block %llu in inode #%lu",
+ ei->i_file_acl, inode->i_ino);
+ ret = -EIO;
+ goto bad_inode;
+ } else if (ei->i_flags & EXT4_EXTENTS_FL) {
+ if (S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
+ (S_ISLNK(inode->i_mode) &&
+ !ext4_inode_is_fast_symlink(inode)))
+ /* Validate extent which is part of inode */
+ ret = ext4_ext_check_inode(inode);
+ } else if (S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
+ (S_ISLNK(inode->i_mode) &&
+ !ext4_inode_is_fast_symlink(inode))) {
+ /* Validate block references which are part of inode */
+ ret = ext4_check_inode_blockref(inode);
+ }
+ if (ret) {
+ brelse(bh);
+ goto bad_inode;
+ }
+
if (S_ISREG(inode->i_mode)) {
inode->i_op = &ext4_file_inode_operations;
inode->i_fop = &ext4_file_operations;
inode->i_op = &ext4_dir_inode_operations;
inode->i_fop = &ext4_dir_operations;
} else if (S_ISLNK(inode->i_mode)) {
- if (ext4_inode_is_fast_symlink(inode))
+ if (ext4_inode_is_fast_symlink(inode)) {
inode->i_op = &ext4_fast_symlink_inode_operations;
- else {
+ nd_terminate_link(ei->i_data, inode->i_size,
+ sizeof(ei->i_data) - 1);
+ } else {
inode->i_op = &ext4_symlink_inode_operations;
ext4_set_aops(inode);
}
- } else {
+ } else if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode) ||
+ S_ISFIFO(inode->i_mode) || S_ISSOCK(inode->i_mode)) {
inode->i_op = &ext4_special_inode_operations;
if (raw_inode->i_block[0])
init_special_inode(inode, inode->i_mode,
else
init_special_inode(inode, inode->i_mode,
new_decode_dev(le32_to_cpu(raw_inode->i_block[1])));
+ } else {
+ brelse(bh);
+ ret = -EIO;
+ ext4_error(inode->i_sb, __func__,
+ "bogus i_mode (%o) for inode=%lu",
+ inode->i_mode, inode->i_ino);
+ goto bad_inode;
}
- brelse (iloc.bh);
+ brelse(iloc.bh);
ext4_set_inode_flags(inode);
unlock_new_inode(inode);
return inode;
struct inode *inode = &(ei->vfs_inode);
u64 i_blocks = inode->i_blocks;
struct super_block *sb = inode->i_sb;
- int err = 0;
if (i_blocks <= ~0U) {
/*
raw_inode->i_blocks_lo = cpu_to_le32(i_blocks);
raw_inode->i_blocks_high = 0;
ei->i_flags &= ~EXT4_HUGE_FILE_FL;
- } else if (i_blocks <= 0xffffffffffffULL) {
+ return 0;
+ }
+ if (!EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_HUGE_FILE))
+ return -EFBIG;
+
+ if (i_blocks <= 0xffffffffffffULL) {
/*
* i_blocks can be represented in a 48 bit variable
* as multiple of 512 bytes
*/
- err = ext4_update_rocompat_feature(handle, sb,
- EXT4_FEATURE_RO_COMPAT_HUGE_FILE);
- if (err)
- goto err_out;
- /* i_block is stored in the split 48 bit fields */
raw_inode->i_blocks_lo = cpu_to_le32(i_blocks);
raw_inode->i_blocks_high = cpu_to_le16(i_blocks >> 32);
ei->i_flags &= ~EXT4_HUGE_FILE_FL;
} else {
- /*
- * i_blocks should be represented in a 48 bit variable
- * as multiple of file system block size
- */
- err = ext4_update_rocompat_feature(handle, sb,
- EXT4_FEATURE_RO_COMPAT_HUGE_FILE);
- if (err)
- goto err_out;
ei->i_flags |= EXT4_HUGE_FILE_FL;
/* i_block is stored in file system block size */
i_blocks = i_blocks >> (inode->i_blkbits - 9);
raw_inode->i_blocks_lo = cpu_to_le32(i_blocks);
raw_inode->i_blocks_high = cpu_to_le16(i_blocks >> 32);
}
-err_out:
- return err;
+ return 0;
}
/*
ext4_get_inode_flags(ei);
raw_inode->i_mode = cpu_to_le16(inode->i_mode);
- if(!(test_opt(inode->i_sb, NO_UID32))) {
+ if (!(test_opt(inode->i_sb, NO_UID32))) {
raw_inode->i_uid_low = cpu_to_le16(low_16_bits(inode->i_uid));
raw_inode->i_gid_low = cpu_to_le16(low_16_bits(inode->i_gid));
/*
* Fix up interoperability with old kernels. Otherwise, old inodes get
* re-used with the upper 16 bits of the uid/gid intact
*/
- if(!ei->i_dtime) {
+ if (!ei->i_dtime) {
raw_inode->i_uid_high =
cpu_to_le16(high_16_bits(inode->i_uid));
raw_inode->i_gid_high =
if (ext4_inode_blocks_set(handle, raw_inode, ei))
goto out_brelse;
raw_inode->i_dtime = cpu_to_le32(ei->i_dtime);
- /* clear the migrate flag in the raw_inode */
- raw_inode->i_flags = cpu_to_le32(ei->i_flags & ~EXT4_EXT_MIGRATE);
+ raw_inode->i_flags = cpu_to_le32(ei->i_flags);
if (EXT4_SB(inode->i_sb)->s_es->s_creator_os !=
cpu_to_le32(EXT4_OS_HURD))
raw_inode->i_file_acl_high =
EXT4_SET_RO_COMPAT_FEATURE(sb,
EXT4_FEATURE_RO_COMPAT_LARGE_FILE);
sb->s_dirt = 1;
- handle->h_sync = 1;
- err = ext4_journal_dirty_metadata(handle,
+ ext4_handle_sync(handle);
+ err = ext4_handle_dirty_metadata(handle, inode,
EXT4_SB(sb)->s_sbh);
}
}
cpu_to_le32(new_encode_dev(inode->i_rdev));
raw_inode->i_block[2] = 0;
}
- } else for (block = 0; block < EXT4_N_BLOCKS; block++)
- raw_inode->i_block[block] = ei->i_data[block];
+ } else
+ for (block = 0; block < EXT4_N_BLOCKS; block++)
+ raw_inode->i_block[block] = ei->i_data[block];
raw_inode->i_disk_version = cpu_to_le32(inode->i_version);
if (ei->i_extra_isize) {
raw_inode->i_extra_isize = cpu_to_le16(ei->i_extra_isize);
}
-
- BUFFER_TRACE(bh, "call ext4_journal_dirty_metadata");
- rc = ext4_journal_dirty_metadata(handle, bh);
+ BUFFER_TRACE(bh, "call ext4_handle_dirty_metadata");
+ rc = ext4_handle_dirty_metadata(handle, inode, bh);
if (!err)
err = rc;
ei->i_state &= ~EXT4_STATE_NEW;
out_brelse:
- brelse (bh);
+ brelse(bh);
ext4_std_error(inode->i_sb, err);
return err;
}
*/
int ext4_write_inode(struct inode *inode, int wait)
{
+ int err;
+
if (current->flags & PF_MEMALLOC)
return 0;
- if (ext4_journal_current_handle()) {
- jbd_debug(1, "called recursively, non-PF_MEMALLOC!\n");
- dump_stack();
- return -EIO;
- }
+ if (EXT4_SB(inode->i_sb)->s_journal) {
+ if (ext4_journal_current_handle()) {
+ jbd_debug(1, "called recursively, non-PF_MEMALLOC!\n");
+ dump_stack();
+ return -EIO;
+ }
- if (!wait)
- return 0;
+ if (!wait)
+ return 0;
+
+ err = ext4_force_commit(inode->i_sb);
+ } else {
+ struct ext4_iloc iloc;
- return ext4_force_commit(inode->i_sb);
+ err = ext4_get_inode_loc(inode, &iloc);
+ if (err)
+ return err;
+ if (wait)
+ sync_dirty_buffer(iloc.bh);
+ if (buffer_req(iloc.bh) && !buffer_uptodate(iloc.bh)) {
+ ext4_error(inode->i_sb, __func__,
+ "IO error syncing inode, "
+ "inode=%lu, block=%llu",
+ inode->i_ino,
+ (unsigned long long)iloc.bh->b_blocknr);
+ err = -EIO;
+ }
+ }
+ return err;
}
/*
* be freed, so we have a strong guarantee that no future commit will
* leave these blocks visible to the user.)
*
- * Called with inode->sem down.
+ * Another thing we have to assure is that if we are in ordered mode
+ * and inode is still attached to the committing transaction, we must
+ * we start writeout of all the dirty pages which are being truncated.
+ * This way we are sure that all the data written in the previous
+ * transaction are already on disk (truncate waits for pages under
+ * writeback).
+ *
+ * Called with inode->i_mutex down.
*/
int ext4_setattr(struct dentry *dentry, struct iattr *attr)
{
error = PTR_ERR(handle);
goto err_out;
}
- error = DQUOT_TRANSFER(inode, attr) ? -EDQUOT : 0;
+ error = vfs_dq_transfer(inode, attr) ? -EDQUOT : 0;
if (error) {
ext4_journal_stop(handle);
return error;
if (!error)
error = rc;
ext4_journal_stop(handle);
+
+ if (ext4_should_order_data(inode)) {
+ error = ext4_begin_ordered_truncate(inode,
+ attr->ia_size);
+ if (error) {
+ /* Do as much error cleanup as possible */
+ handle = ext4_journal_start(inode, 3);
+ if (IS_ERR(handle)) {
+ ext4_orphan_del(NULL, inode);
+ goto err_out;
+ }
+ ext4_orphan_del(handle, inode);
+ ext4_journal_stop(handle);
+ goto err_out;
+ }
+ }
}
rc = inode_setattr(inode, attr);
return error;
}
+int ext4_getattr(struct vfsmount *mnt, struct dentry *dentry,
+ struct kstat *stat)
+{
+ struct inode *inode;
+ unsigned long delalloc_blocks;
+
+ inode = dentry->d_inode;
+ generic_fillattr(inode, stat);
+
+ /*
+ * We can't update i_blocks if the block allocation is delayed
+ * otherwise in the case of system crash before the real block
+ * allocation is done, we will have i_blocks inconsistent with
+ * on-disk file blocks.
+ * We always keep i_blocks updated together with real
+ * allocation. But to not confuse with user, stat
+ * will return the blocks that include the delayed allocation
+ * blocks for this file.
+ */
+ spin_lock(&EXT4_I(inode)->i_block_reservation_lock);
+ delalloc_blocks = EXT4_I(inode)->i_reserved_data_blocks;
+ spin_unlock(&EXT4_I(inode)->i_block_reservation_lock);
+
+ stat->blocks += (delalloc_blocks << inode->i_sb->s_blocksize_bits)>>9;
+ return 0;
+}
+
+static int ext4_indirect_trans_blocks(struct inode *inode, int nrblocks,
+ int chunk)
+{
+ int indirects;
+
+ /* if nrblocks are contiguous */
+ if (chunk) {
+ /*
+ * With N contiguous data blocks, it need at most
+ * N/EXT4_ADDR_PER_BLOCK(inode->i_sb) indirect blocks
+ * 2 dindirect blocks
+ * 1 tindirect block
+ */
+ indirects = nrblocks / EXT4_ADDR_PER_BLOCK(inode->i_sb);
+ return indirects + 3;
+ }
+ /*
+ * if nrblocks are not contiguous, worse case, each block touch
+ * a indirect block, and each indirect block touch a double indirect
+ * block, plus a triple indirect block
+ */
+ indirects = nrblocks * 2 + 1;
+ return indirects;
+}
+
+static int ext4_index_trans_blocks(struct inode *inode, int nrblocks, int chunk)
+{
+ if (!(EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL))
+ return ext4_indirect_trans_blocks(inode, nrblocks, chunk);
+ return ext4_ext_index_trans_blocks(inode, nrblocks, chunk);
+}
/*
- * How many blocks doth make a writepage()?
- *
- * With N blocks per page, it may be:
- * N data blocks
- * 2 indirect block
- * 2 dindirect
- * 1 tindirect
- * N+5 bitmap blocks (from the above)
- * N+5 group descriptor summary blocks
- * 1 inode block
- * 1 superblock.
- * 2 * EXT4_SINGLEDATA_TRANS_BLOCKS for the quote files
+ * Account for index blocks, block groups bitmaps and block group
+ * descriptor blocks if modify datablocks and index blocks
+ * worse case, the indexs blocks spread over different block groups
*
- * 3 * (N + 5) + 2 + 2 * EXT4_SINGLEDATA_TRANS_BLOCKS
+ * If datablocks are discontiguous, they are possible to spread over
+ * different block groups too. If they are contiuguous, with flexbg,
+ * they could still across block group boundary.
*
- * With ordered or writeback data it's the same, less the N data blocks.
+ * Also account for superblock, inode, quota and xattr blocks
+ */
+int ext4_meta_trans_blocks(struct inode *inode, int nrblocks, int chunk)
+{
+ ext4_group_t groups, ngroups = ext4_get_groups_count(inode->i_sb);
+ int gdpblocks;
+ int idxblocks;
+ int ret = 0;
+
+ /*
+ * How many index blocks need to touch to modify nrblocks?
+ * The "Chunk" flag indicating whether the nrblocks is
+ * physically contiguous on disk
+ *
+ * For Direct IO and fallocate, they calls get_block to allocate
+ * one single extent at a time, so they could set the "Chunk" flag
+ */
+ idxblocks = ext4_index_trans_blocks(inode, nrblocks, chunk);
+
+ ret = idxblocks;
+
+ /*
+ * Now let's see how many group bitmaps and group descriptors need
+ * to account
+ */
+ groups = idxblocks;
+ if (chunk)
+ groups += 1;
+ else
+ groups += nrblocks;
+
+ gdpblocks = groups;
+ if (groups > ngroups)
+ groups = ngroups;
+ if (groups > EXT4_SB(inode->i_sb)->s_gdb_count)
+ gdpblocks = EXT4_SB(inode->i_sb)->s_gdb_count;
+
+ /* bitmaps and block group descriptor blocks */
+ ret += groups + gdpblocks;
+
+ /* Blocks for super block, inode, quota and xattr blocks */
+ ret += EXT4_META_TRANS_BLOCKS(inode->i_sb);
+
+ return ret;
+}
+
+/*
+ * Calulate the total number of credits to reserve to fit
+ * the modification of a single pages into a single transaction,
+ * which may include multiple chunks of block allocations.
*
- * If the inode's direct blocks can hold an integral number of pages then a
- * page cannot straddle two indirect blocks, and we can only touch one indirect
- * and dindirect block, and the "5" above becomes "3".
+ * This could be called via ext4_write_begin()
*
- * This still overestimates under most circumstances. If we were to pass the
- * start and end offsets in here as well we could do block_to_path() on each
- * block and work out the exact number of indirects which are touched. Pah.
+ * We need to consider the worse case, when
+ * one new block per extent.
*/
-
int ext4_writepage_trans_blocks(struct inode *inode)
{
int bpp = ext4_journal_blocks_per_page(inode);
- int indirects = (EXT4_NDIR_BLOCKS % bpp) ? 5 : 3;
int ret;
- if (EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL)
- return ext4_ext_writepage_trans_blocks(inode, bpp);
+ ret = ext4_meta_trans_blocks(inode, bpp, 0);
+ /* Account for data blocks for journalled mode */
if (ext4_should_journal_data(inode))
- ret = 3 * (bpp + indirects) + 2;
- else
- ret = 2 * (bpp + indirects) + 2;
-
-#ifdef CONFIG_QUOTA
- /* We know that structure was already allocated during DQUOT_INIT so
- * we will be updating only the data blocks + inodes */
- ret += 2*EXT4_QUOTA_TRANS_BLOCKS(inode->i_sb);
-#endif
-
+ ret += bpp;
return ret;
}
/*
+ * Calculate the journal credits for a chunk of data modification.
+ *
+ * This is called from DIO, fallocate or whoever calling
+ * ext4_get_blocks() to map/allocate a chunk of contiguous disk blocks.
+ *
+ * journal buffers for data blocks are not included here, as DIO
+ * and fallocate do no need to journal data buffers.
+ */
+int ext4_chunk_trans_blocks(struct inode *inode, int nrblocks)
+{
+ return ext4_meta_trans_blocks(inode, nrblocks, 1);
+}
+
+/*
* The caller must have previously called ext4_reserve_inode_write().
* Give this, we know that the caller already has write access to iloc->bh.
*/
int ext4_mark_iloc_dirty(handle_t *handle,
- struct inode *inode, struct ext4_iloc *iloc)
+ struct inode *inode, struct ext4_iloc *iloc)
{
int err = 0;
ext4_reserve_inode_write(handle_t *handle, struct inode *inode,
struct ext4_iloc *iloc)
{
- int err = 0;
- if (handle) {
- err = ext4_get_inode_loc(inode, iloc);
- if (!err) {
- BUFFER_TRACE(iloc->bh, "get_write_access");
- err = ext4_journal_get_write_access(handle, iloc->bh);
- if (err) {
- brelse(iloc->bh);
- iloc->bh = NULL;
- }
+ int err;
+
+ err = ext4_get_inode_loc(inode, iloc);
+ if (!err) {
+ BUFFER_TRACE(iloc->bh, "get_write_access");
+ err = ext4_journal_get_write_access(handle, iloc->bh);
+ if (err) {
+ brelse(iloc->bh);
+ iloc->bh = NULL;
}
}
ext4_std_error(inode->i_sb, err);
might_sleep();
err = ext4_reserve_inode_write(handle, inode, &iloc);
- if (EXT4_I(inode)->i_extra_isize < sbi->s_want_extra_isize &&
+ if (ext4_handle_valid(handle) &&
+ EXT4_I(inode)->i_extra_isize < sbi->s_want_extra_isize &&
!(EXT4_I(inode)->i_state & EXT4_STATE_NO_EXPAND)) {
/*
* We need extra buffer credits since we may write into EA block
EXT4_I(inode)->i_state |= EXT4_STATE_NO_EXPAND;
if (mnt_count !=
le16_to_cpu(sbi->s_es->s_mnt_count)) {
- ext4_warning(inode->i_sb, __FUNCTION__,
+ ext4_warning(inode->i_sb, __func__,
"Unable to expand inode %lu. Delete"
" some EAs or run e2fsck.",
inode->i_ino);
* i_size has been changed by generic_commit_write() and we thus need
* to include the updated inode in the current transaction.
*
- * Also, DQUOT_ALLOC_SPACE() will always dirty the inode when blocks
+ * Also, vfs_dq_alloc_block() will always dirty the inode when blocks
* are allocated to the file.
*
* If the inode is marked synchronous, we don't honour that here - doing
*/
void ext4_dirty_inode(struct inode *inode)
{
- handle_t *current_handle = ext4_journal_current_handle();
handle_t *handle;
handle = ext4_journal_start(inode, 2);
if (IS_ERR(handle))
goto out;
- if (current_handle &&
- current_handle->h_transaction != handle->h_transaction) {
- /* This task has a transaction open against a different fs */
- printk(KERN_EMERG "%s: transactions do not match!\n",
- __FUNCTION__);
- } else {
- jbd_debug(5, "marking dirty. outer handle=%p\n",
- current_handle);
- ext4_mark_inode_dirty(handle, inode);
- }
+
+ ext4_mark_inode_dirty(handle, inode);
+
ext4_journal_stop(handle);
out:
return;
BUFFER_TRACE(iloc.bh, "get_write_access");
err = jbd2_journal_get_write_access(handle, iloc.bh);
if (!err)
- err = ext4_journal_dirty_metadata(handle,
- iloc.bh);
+ err = ext4_handle_dirty_metadata(handle,
+ inode,
+ iloc.bh);
brelse(iloc.bh);
}
}
*/
journal = EXT4_JOURNAL(inode);
+ if (!journal)
+ return 0;
if (is_journal_aborted(journal))
return -EROFS;
return PTR_ERR(handle);
err = ext4_mark_inode_dirty(handle, inode);
- handle->h_sync = 1;
+ ext4_handle_sync(handle);
ext4_journal_stop(handle);
ext4_std_error(inode->i_sb, err);
return err;
}
+
+static int ext4_bh_unmapped(handle_t *handle, struct buffer_head *bh)
+{
+ return !buffer_mapped(bh);
+}
+
+int ext4_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf)
+{
+ struct page *page = vmf->page;
+ loff_t size;
+ unsigned long len;
+ int ret = -EINVAL;
+ void *fsdata;
+ struct file *file = vma->vm_file;
+ struct inode *inode = file->f_path.dentry->d_inode;
+ struct address_space *mapping = inode->i_mapping;
+
+ /*
+ * Get i_alloc_sem to stop truncates messing with the inode. We cannot
+ * get i_mutex because we are already holding mmap_sem.
+ */
+ down_read(&inode->i_alloc_sem);
+ size = i_size_read(inode);
+ if (page->mapping != mapping || size <= page_offset(page)
+ || !PageUptodate(page)) {
+ /* page got truncated from under us? */
+ goto out_unlock;
+ }
+ ret = 0;
+ if (PageMappedToDisk(page))
+ goto out_unlock;
+
+ if (page->index == size >> PAGE_CACHE_SHIFT)
+ len = size & ~PAGE_CACHE_MASK;
+ else
+ len = PAGE_CACHE_SIZE;
+
+ lock_page(page);
+ /*
+ * return if we have all the buffers mapped. This avoid
+ * the need to call write_begin/write_end which does a
+ * journal_start/journal_stop which can block and take
+ * long time
+ */
+ if (page_has_buffers(page)) {
+ if (!walk_page_buffers(NULL, page_buffers(page), 0, len, NULL,
+ ext4_bh_unmapped)) {
+ unlock_page(page);
+ goto out_unlock;
+ }
+ }
+ unlock_page(page);
+ /*
+ * OK, we need to fill the hole... Do write_begin write_end
+ * to do block allocation/reservation.We are not holding
+ * inode.i__mutex here. That allow * parallel write_begin,
+ * write_end call. lock_page prevent this from happening
+ * on the same page though
+ */
+ ret = mapping->a_ops->write_begin(file, mapping, page_offset(page),
+ len, AOP_FLAG_UNINTERRUPTIBLE, &page, &fsdata);
+ if (ret < 0)
+ goto out_unlock;
+ ret = mapping->a_ops->write_end(file, mapping, page_offset(page),
+ len, len, page, fsdata);
+ if (ret < 0)
+ goto out_unlock;
+ ret = 0;
+out_unlock:
+ if (ret)
+ ret = VM_FAULT_SIGBUS;
+ up_read(&inode->i_alloc_sem);
+ return ret;
+}
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff