ext4: Reorder fs/Makefile so that ext2 root fs's are mounted using ext2
[safe/jmp/linux-2.6] / fs / ext4 / extents.c
index 8593e59..e2eab19 100644 (file)
@@ -32,7 +32,6 @@
 #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/slab.h>
 #include <linux/falloc.h>
-#include <linux/ext4_fs_extents.h>
 #include <asm/uaccess.h>
+#include <linux/fiemap.h>
+#include "ext4_jbd2.h"
+#include "ext4_extents.h"
 
 
 /*
@@ -61,7 +62,7 @@ static ext4_fsblk_t ext_pblock(struct ext4_extent *ex)
  * idx_pblock:
  * combine low and high parts of a leaf physical block number into ext4_fsblk_t
  */
-static ext4_fsblk_t idx_pblock(struct ext4_extent_idx *ix)
+ext4_fsblk_t idx_pblock(struct ext4_extent_idx *ix)
 {
        ext4_fsblk_t block;
 
@@ -75,7 +76,7 @@ static ext4_fsblk_t idx_pblock(struct ext4_extent_idx *ix)
  * stores a large physical block number into an extent struct,
  * breaking it into parts
  */
-static void ext4_ext_store_pblock(struct ext4_extent *ex, ext4_fsblk_t pb)
+void ext4_ext_store_pblock(struct ext4_extent *ex, ext4_fsblk_t pb)
 {
        ex->ee_start_lo = cpu_to_le32((unsigned long) (pb & 0xffffffff));
        ex->ee_start_hi = cpu_to_le16((unsigned long) ((pb >> 31) >> 1) & 0xffff);
@@ -92,17 +93,18 @@ static void ext4_idx_store_pblock(struct ext4_extent_idx *ix, ext4_fsblk_t pb)
        ix->ei_leaf_hi = cpu_to_le16((unsigned long) ((pb >> 31) >> 1) & 0xffff);
 }
 
-static handle_t *ext4_ext_journal_restart(handle_t *handle, int needed)
+static int ext4_ext_journal_restart(handle_t *handle, int needed)
 {
        int err;
 
+       if (!ext4_handle_valid(handle))
+               return 0;
        if (handle->h_buffer_credits > needed)
-               return handle;
-       if (!ext4_journal_extend(handle, needed))
-               return handle;
-       err = ext4_journal_restart(handle, needed);
-
-       return handle;
+               return 0;
+       err = ext4_journal_extend(handle, needed);
+       if (err <= 0)
+               return err;
+       return ext4_journal_restart(handle, needed);
 }
 
 /*
@@ -134,7 +136,7 @@ static int ext4_ext_dirty(handle_t *handle, struct inode *inode,
        int err;
        if (path->p_bh) {
                /* path points to block */
-               err = ext4_journal_dirty_metadata(handle, path->p_bh);
+               err = ext4_handle_dirty_metadata(handle, inode, path->p_bh);
        } else {
                /* path points to leaf/index in inode body */
                err = ext4_mark_inode_dirty(handle, inode);
@@ -148,6 +150,7 @@ static ext4_fsblk_t ext4_ext_find_goal(struct inode *inode,
 {
        struct ext4_inode_info *ei = EXT4_I(inode);
        ext4_fsblk_t bg_start;
+       ext4_fsblk_t last_block;
        ext4_grpblk_t colour;
        int depth;
 
@@ -169,20 +172,28 @@ static ext4_fsblk_t ext4_ext_find_goal(struct inode *inode,
        /* OK. use inode's group */
        bg_start = (ei->i_block_group * EXT4_BLOCKS_PER_GROUP(inode->i_sb)) +
                le32_to_cpu(EXT4_SB(inode->i_sb)->s_es->s_first_data_block);
-       colour = (current->pid % 16) *
+       last_block = ext4_blocks_count(EXT4_SB(inode->i_sb)->s_es) - 1;
+
+       if (bg_start + EXT4_BLOCKS_PER_GROUP(inode->i_sb) <= last_block)
+               colour = (current->pid % 16) *
                        (EXT4_BLOCKS_PER_GROUP(inode->i_sb) / 16);
+       else
+               colour = (current->pid % 16) * ((last_block - bg_start) / 16);
        return bg_start + colour + block;
 }
 
+/*
+ * Allocation for a meta data block
+ */
 static ext4_fsblk_t
-ext4_ext_new_block(handle_t *handle, struct inode *inode,
+ext4_ext_new_meta_block(handle_t *handle, struct inode *inode,
                        struct ext4_ext_path *path,
                        struct ext4_extent *ex, int *err)
 {
        ext4_fsblk_t goal, newblock;
 
        goal = ext4_ext_find_goal(inode, path, le32_to_cpu(ex->ee_block));
-       newblock = ext4_new_block(handle, inode, goal, err);
+       newblock = ext4_new_meta_blocks(handle, inode, goal, NULL, err);
        return newblock;
 }
 
@@ -240,6 +251,36 @@ static int ext4_ext_space_root_idx(struct inode *inode)
        return size;
 }
 
+/*
+ * Calculate the number of metadata blocks needed
+ * to allocate @blocks
+ * Worse case is one block per extent
+ */
+int ext4_ext_calc_metadata_amount(struct inode *inode, int blocks)
+{
+       int lcap, icap, rcap, leafs, idxs, num;
+       int newextents = blocks;
+
+       rcap = ext4_ext_space_root_idx(inode);
+       lcap = ext4_ext_space_block(inode);
+       icap = ext4_ext_space_block_idx(inode);
+
+       /* number of new leaf blocks needed */
+       num = leafs = (newextents + lcap - 1) / lcap;
+
+       /*
+        * Worse case, we need separate index block(s)
+        * to link all new leaf blocks
+        */
+       idxs = (leafs + icap - 1) / icap;
+       do {
+               num += idxs;
+               idxs = (idxs + icap - 1) / icap;
+       } while (idxs > rcap);
+
+       return num;
+}
+
 static int
 ext4_ext_max_entries(struct inode *inode, int depth)
 {
@@ -302,7 +343,7 @@ corrupted:
 }
 
 #define ext4_ext_check_header(inode, eh, depth)        \
-       __ext4_ext_check_header(__FUNCTION__, inode, eh, depth)
+       __ext4_ext_check_header(__func__, inode, eh, depth)
 
 #ifdef EXT_DEBUG
 static void ext4_ext_show_path(struct inode *inode, struct ext4_ext_path *path)
@@ -345,11 +386,11 @@ static void ext4_ext_show_leaf(struct inode *inode, struct ext4_ext_path *path)
        ext_debug("\n");
 }
 #else
-#define ext4_ext_show_path(inode,path)
-#define ext4_ext_show_leaf(inode,path)
+#define ext4_ext_show_path(inode, path)
+#define ext4_ext_show_leaf(inode, path)
 #endif
 
-static void ext4_ext_drop_refs(struct ext4_ext_path *path)
+void ext4_ext_drop_refs(struct ext4_ext_path *path)
 {
        int depth = path->p_depth;
        int i;
@@ -402,9 +443,10 @@ ext4_ext_binsearch_idx(struct inode *inode,
                for (k = 0; k < le16_to_cpu(eh->eh_entries); k++, ix++) {
                  if (k != 0 &&
                      le32_to_cpu(ix->ei_block) <= le32_to_cpu(ix[-1].ei_block)) {
-                               printk("k=%d, ix=0x%p, first=0x%p\n", k,
-                                       ix, EXT_FIRST_INDEX(eh));
-                               printk("%u <= %u\n",
+                               printk(KERN_DEBUG "k=%d, ix=0x%p, "
+                                      "first=0x%p\n", k,
+                                      ix, EXT_FIRST_INDEX(eh));
+                               printk(KERN_DEBUG "%u <= %u\n",
                                       le32_to_cpu(ix->ei_block),
                                       le32_to_cpu(ix[-1].ei_block));
                        }
@@ -518,6 +560,7 @@ ext4_ext_find_extent(struct inode *inode, ext4_lblk_t block,
                alloc = 1;
        }
        path[0].p_hdr = eh;
+       path[0].p_bh = NULL;
 
        i = depth;
        /* walk through the tree */
@@ -546,12 +589,14 @@ ext4_ext_find_extent(struct inode *inode, ext4_lblk_t block,
        }
 
        path[ppos].p_depth = i;
-       path[ppos].p_hdr = eh;
        path[ppos].p_ext = NULL;
        path[ppos].p_idx = NULL;
 
        /* find extent */
        ext4_ext_binsearch(inode, path + ppos, block);
+       /* if not an empty leaf */
+       if (path[ppos].p_ext)
+               path[ppos].p_block = ext_pblock(path[ppos].p_ext);
 
        ext4_ext_show_path(inode, path);
 
@@ -608,7 +653,7 @@ static int ext4_ext_insert_index(handle_t *handle, struct inode *inode,
 
        ix->ei_block = cpu_to_le32(logical);
        ext4_idx_store_pblock(ix, ptr);
-       curp->p_hdr->eh_entries = cpu_to_le16(le16_to_cpu(curp->p_hdr->eh_entries)+1);
+       le16_add_cpu(&curp->p_hdr->eh_entries, 1);
 
        BUG_ON(le16_to_cpu(curp->p_hdr->eh_entries)
                             > le16_to_cpu(curp->p_hdr->eh_max));
@@ -682,7 +727,8 @@ static int ext4_ext_split(handle_t *handle, struct inode *inode,
        /* allocate all needed blocks */
        ext_debug("allocate %d blocks for indexes/leaf\n", depth - at);
        for (a = 0; a < depth - at; a++) {
-               newblock = ext4_ext_new_block(handle, inode, path, newext, &err);
+               newblock = ext4_ext_new_meta_block(handle, inode, path,
+                                                  newext, &err);
                if (newblock == 0)
                        goto cleanup;
                ablocks[a] = newblock;
@@ -730,13 +776,13 @@ static int ext4_ext_split(handle_t *handle, struct inode *inode,
        }
        if (m) {
                memmove(ex, path[depth].p_ext-m, sizeof(struct ext4_extent)*m);
-               neh->eh_entries = cpu_to_le16(le16_to_cpu(neh->eh_entries)+m);
+               le16_add_cpu(&neh->eh_entries, m);
        }
 
        set_buffer_uptodate(bh);
        unlock_buffer(bh);
 
-       err = ext4_journal_dirty_metadata(handle, bh);
+       err = ext4_handle_dirty_metadata(handle, inode, bh);
        if (err)
                goto cleanup;
        brelse(bh);
@@ -747,8 +793,7 @@ static int ext4_ext_split(handle_t *handle, struct inode *inode,
                err = ext4_ext_get_access(handle, inode, path + depth);
                if (err)
                        goto cleanup;
-               path[depth].p_hdr->eh_entries =
-                    cpu_to_le16(le16_to_cpu(path[depth].p_hdr->eh_entries)-m);
+               le16_add_cpu(&path[depth].p_hdr->eh_entries, -m);
                err = ext4_ext_dirty(handle, inode, path + depth);
                if (err)
                        goto cleanup;
@@ -811,13 +856,12 @@ static int ext4_ext_split(handle_t *handle, struct inode *inode,
                if (m) {
                        memmove(++fidx, path[i].p_idx - m,
                                sizeof(struct ext4_extent_idx) * m);
-                       neh->eh_entries =
-                               cpu_to_le16(le16_to_cpu(neh->eh_entries) + m);
+                       le16_add_cpu(&neh->eh_entries, m);
                }
                set_buffer_uptodate(bh);
                unlock_buffer(bh);
 
-               err = ext4_journal_dirty_metadata(handle, bh);
+               err = ext4_handle_dirty_metadata(handle, inode, bh);
                if (err)
                        goto cleanup;
                brelse(bh);
@@ -828,7 +872,7 @@ static int ext4_ext_split(handle_t *handle, struct inode *inode,
                        err = ext4_ext_get_access(handle, inode, path + i);
                        if (err)
                                goto cleanup;
-                       path[i].p_hdr->eh_entries = cpu_to_le16(le16_to_cpu(path[i].p_hdr->eh_entries)-m);
+                       le16_add_cpu(&path[i].p_hdr->eh_entries, -m);
                        err = ext4_ext_dirty(handle, inode, path + i);
                        if (err)
                                goto cleanup;
@@ -853,7 +897,7 @@ cleanup:
                for (i = 0; i < depth; i++) {
                        if (!ablocks[i])
                                continue;
-                       ext4_free_blocks(handle, inode, ablocks[i], 1);
+                       ext4_free_blocks(handle, inode, ablocks[i], 1, 1);
                }
        }
        kfree(ablocks);
@@ -880,7 +924,7 @@ static int ext4_ext_grow_indepth(handle_t *handle, struct inode *inode,
        ext4_fsblk_t newblock;
        int err = 0;
 
-       newblock = ext4_ext_new_block(handle, inode, path, newext, &err);
+       newblock = ext4_ext_new_meta_block(handle, inode, path, newext, &err);
        if (newblock == 0)
                return err;
 
@@ -913,7 +957,7 @@ static int ext4_ext_grow_indepth(handle_t *handle, struct inode *inode,
        set_buffer_uptodate(bh);
        unlock_buffer(bh);
 
-       err = ext4_journal_dirty_metadata(handle, bh);
+       err = ext4_handle_dirty_metadata(handle, inode, bh);
        if (err)
                goto out;
 
@@ -977,6 +1021,8 @@ repeat:
                /* if we found index with free entry, then use that
                 * entry: create all needed subtree and add new leaf */
                err = ext4_ext_split(handle, inode, path, newext, i);
+               if (err)
+                       goto out;
 
                /* refill path */
                ext4_ext_drop_refs(path);
@@ -1017,6 +1063,147 @@ out:
 }
 
 /*
+ * search the closest allocated block to the left for *logical
+ * and returns it at @logical + it's physical address at @phys
+ * if *logical is the smallest allocated block, the function
+ * returns 0 at @phys
+ * return value contains 0 (success) or error code
+ */
+int
+ext4_ext_search_left(struct inode *inode, struct ext4_ext_path *path,
+                       ext4_lblk_t *logical, ext4_fsblk_t *phys)
+{
+       struct ext4_extent_idx *ix;
+       struct ext4_extent *ex;
+       int depth, ee_len;
+
+       BUG_ON(path == NULL);
+       depth = path->p_depth;
+       *phys = 0;
+
+       if (depth == 0 && path->p_ext == NULL)
+               return 0;
+
+       /* usually extent in the path covers blocks smaller
+        * then *logical, but it can be that extent is the
+        * first one in the file */
+
+       ex = path[depth].p_ext;
+       ee_len = ext4_ext_get_actual_len(ex);
+       if (*logical < le32_to_cpu(ex->ee_block)) {
+               BUG_ON(EXT_FIRST_EXTENT(path[depth].p_hdr) != ex);
+               while (--depth >= 0) {
+                       ix = path[depth].p_idx;
+                       BUG_ON(ix != EXT_FIRST_INDEX(path[depth].p_hdr));
+               }
+               return 0;
+       }
+
+       BUG_ON(*logical < (le32_to_cpu(ex->ee_block) + ee_len));
+
+       *logical = le32_to_cpu(ex->ee_block) + ee_len - 1;
+       *phys = ext_pblock(ex) + ee_len - 1;
+       return 0;
+}
+
+/*
+ * search the closest allocated block to the right for *logical
+ * and returns it at @logical + it's physical address at @phys
+ * if *logical is the smallest allocated block, the function
+ * returns 0 at @phys
+ * return value contains 0 (success) or error code
+ */
+int
+ext4_ext_search_right(struct inode *inode, struct ext4_ext_path *path,
+                       ext4_lblk_t *logical, ext4_fsblk_t *phys)
+{
+       struct buffer_head *bh = NULL;
+       struct ext4_extent_header *eh;
+       struct ext4_extent_idx *ix;
+       struct ext4_extent *ex;
+       ext4_fsblk_t block;
+       int depth, ee_len;
+
+       BUG_ON(path == NULL);
+       depth = path->p_depth;
+       *phys = 0;
+
+       if (depth == 0 && path->p_ext == NULL)
+               return 0;
+
+       /* usually extent in the path covers blocks smaller
+        * then *logical, but it can be that extent is the
+        * first one in the file */
+
+       ex = path[depth].p_ext;
+       ee_len = ext4_ext_get_actual_len(ex);
+       if (*logical < le32_to_cpu(ex->ee_block)) {
+               BUG_ON(EXT_FIRST_EXTENT(path[depth].p_hdr) != ex);
+               while (--depth >= 0) {
+                       ix = path[depth].p_idx;
+                       BUG_ON(ix != EXT_FIRST_INDEX(path[depth].p_hdr));
+               }
+               *logical = le32_to_cpu(ex->ee_block);
+               *phys = ext_pblock(ex);
+               return 0;
+       }
+
+       BUG_ON(*logical < (le32_to_cpu(ex->ee_block) + ee_len));
+
+       if (ex != EXT_LAST_EXTENT(path[depth].p_hdr)) {
+               /* next allocated block in this leaf */
+               ex++;
+               *logical = le32_to_cpu(ex->ee_block);
+               *phys = ext_pblock(ex);
+               return 0;
+       }
+
+       /* go up and search for index to the right */
+       while (--depth >= 0) {
+               ix = path[depth].p_idx;
+               if (ix != EXT_LAST_INDEX(path[depth].p_hdr))
+                       goto got_index;
+       }
+
+       /* we've gone up to the root and found no index to the right */
+       return 0;
+
+got_index:
+       /* we've found index to the right, let's
+        * follow it and find the closest allocated
+        * block to the right */
+       ix++;
+       block = idx_pblock(ix);
+       while (++depth < path->p_depth) {
+               bh = sb_bread(inode->i_sb, block);
+               if (bh == NULL)
+                       return -EIO;
+               eh = ext_block_hdr(bh);
+               if (ext4_ext_check_header(inode, eh, depth)) {
+                       put_bh(bh);
+                       return -EIO;
+               }
+               ix = EXT_FIRST_INDEX(eh);
+               block = idx_pblock(ix);
+               put_bh(bh);
+       }
+
+       bh = sb_bread(inode->i_sb, block);
+       if (bh == NULL)
+               return -EIO;
+       eh = ext_block_hdr(bh);
+       if (ext4_ext_check_header(inode, eh, path->p_depth - depth)) {
+               put_bh(bh);
+               return -EIO;
+       }
+       ex = EXT_FIRST_EXTENT(eh);
+       *logical = le32_to_cpu(ex->ee_block);
+       *phys = ext_pblock(ex);
+       put_bh(bh);
+       return 0;
+}
+
+/*
  * ext4_ext_next_allocated_block:
  * returns allocated block in subsequent extent or EXT_MAX_BLOCK.
  * NOTE: it considers block number from index entry as
@@ -1174,7 +1361,7 @@ ext4_can_extents_be_merged(struct inode *inode, struct ext4_extent *ex1,
        if (ext1_ee_len + ext2_ee_len > max_len)
                return 0;
 #ifdef AGGRESSIVE_TEST
-       if (le16_to_cpu(ex1->ee_len) >= 4)
+       if (ext1_ee_len >= 4)
                return 0;
 #endif
 
@@ -1219,7 +1406,7 @@ int ext4_ext_try_to_merge(struct inode *inode,
                                * sizeof(struct ext4_extent);
                        memmove(ex + 1, ex + 2, len);
                }
-               eh->eh_entries = cpu_to_le16(le16_to_cpu(eh->eh_entries) - 1);
+               le16_add_cpu(&eh->eh_entries, -1);
                merge_done = 1;
                WARN_ON(eh->eh_entries == 0);
                if (!eh->eh_entries)
@@ -1255,7 +1442,7 @@ unsigned int ext4_ext_check_overlap(struct inode *inode,
 
        /*
         * get the next allocated block if the extent in the path
-        * is before the requested block(s) 
+        * is before the requested block(s)
         */
        if (b2 < b1) {
                b2 = ext4_ext_next_allocated_block(path);
@@ -1289,7 +1476,7 @@ int ext4_ext_insert_extent(handle_t *handle, struct inode *inode,
                                struct ext4_ext_path *path,
                                struct ext4_extent *newext)
 {
-       struct ext4_extent_header * eh;
+       struct ext4_extent_header *eh;
        struct ext4_extent *ex, *fex;
        struct ext4_extent *nearex; /* nearest extent */
        struct ext4_ext_path *npath = NULL;
@@ -1410,7 +1597,7 @@ has_space:
                path[depth].p_ext = nearex;
        }
 
-       eh->eh_entries = cpu_to_le16(le16_to_cpu(eh->eh_entries)+1);
+       le16_add_cpu(&eh->eh_entries, 1);
        nearex = path[depth].p_ext;
        nearex->ee_block = newext->ee_block;
        ext4_ext_store_pblock(nearex, ext_pblock(newext));
@@ -1434,11 +1621,117 @@ cleanup:
                ext4_ext_drop_refs(npath);
                kfree(npath);
        }
-       ext4_ext_tree_changed(inode);
        ext4_ext_invalidate_cache(inode);
        return err;
 }
 
+int ext4_ext_walk_space(struct inode *inode, ext4_lblk_t block,
+                       ext4_lblk_t num, ext_prepare_callback func,
+                       void *cbdata)
+{
+       struct ext4_ext_path *path = NULL;
+       struct ext4_ext_cache cbex;
+       struct ext4_extent *ex;
+       ext4_lblk_t next, start = 0, end = 0;
+       ext4_lblk_t last = block + num;
+       int depth, exists, err = 0;
+
+       BUG_ON(func == NULL);
+       BUG_ON(inode == NULL);
+
+       while (block < last && block != EXT_MAX_BLOCK) {
+               num = last - block;
+               /* find extent for this block */
+               path = ext4_ext_find_extent(inode, block, path);
+               if (IS_ERR(path)) {
+                       err = PTR_ERR(path);
+                       path = NULL;
+                       break;
+               }
+
+               depth = ext_depth(inode);
+               BUG_ON(path[depth].p_hdr == NULL);
+               ex = path[depth].p_ext;
+               next = ext4_ext_next_allocated_block(path);
+
+               exists = 0;
+               if (!ex) {
+                       /* there is no extent yet, so try to allocate
+                        * all requested space */
+                       start = block;
+                       end = block + num;
+               } else if (le32_to_cpu(ex->ee_block) > block) {
+                       /* need to allocate space before found extent */
+                       start = block;
+                       end = le32_to_cpu(ex->ee_block);
+                       if (block + num < end)
+                               end = block + num;
+               } else if (block >= le32_to_cpu(ex->ee_block)
+                                       + ext4_ext_get_actual_len(ex)) {
+                       /* need to allocate space after found extent */
+                       start = block;
+                       end = block + num;
+                       if (end >= next)
+                               end = next;
+               } else if (block >= le32_to_cpu(ex->ee_block)) {
+                       /*
+                        * some part of requested space is covered
+                        * by found extent
+                        */
+                       start = block;
+                       end = le32_to_cpu(ex->ee_block)
+                               + ext4_ext_get_actual_len(ex);
+                       if (block + num < end)
+                               end = block + num;
+                       exists = 1;
+               } else {
+                       BUG();
+               }
+               BUG_ON(end <= start);
+
+               if (!exists) {
+                       cbex.ec_block = start;
+                       cbex.ec_len = end - start;
+                       cbex.ec_start = 0;
+                       cbex.ec_type = EXT4_EXT_CACHE_GAP;
+               } else {
+                       cbex.ec_block = le32_to_cpu(ex->ee_block);
+                       cbex.ec_len = ext4_ext_get_actual_len(ex);
+                       cbex.ec_start = ext_pblock(ex);
+                       cbex.ec_type = EXT4_EXT_CACHE_EXTENT;
+               }
+
+               BUG_ON(cbex.ec_len == 0);
+               err = func(inode, path, &cbex, ex, cbdata);
+               ext4_ext_drop_refs(path);
+
+               if (err < 0)
+                       break;
+
+               if (err == EXT_REPEAT)
+                       continue;
+               else if (err == EXT_BREAK) {
+                       err = 0;
+                       break;
+               }
+
+               if (ext_depth(inode) != depth) {
+                       /* depth was changed. we have to realloc path */
+                       kfree(path);
+                       path = NULL;
+               }
+
+               block = cbex.ec_block + cbex.ec_len;
+       }
+
+       if (path) {
+               ext4_ext_drop_refs(path);
+               kfree(path);
+       }
+
+       return err;
+}
+
 static void
 ext4_ext_put_in_cache(struct inode *inode, ext4_lblk_t block,
                        __u32 len, ext4_fsblk_t start, int type)
@@ -1549,66 +1842,73 @@ static int ext4_ext_rm_idx(handle_t *handle, struct inode *inode,
        err = ext4_ext_get_access(handle, inode, path);
        if (err)
                return err;
-       path->p_hdr->eh_entries = cpu_to_le16(le16_to_cpu(path->p_hdr->eh_entries)-1);
+       le16_add_cpu(&path->p_hdr->eh_entries, -1);
        err = ext4_ext_dirty(handle, inode, path);
        if (err)
                return err;
        ext_debug("index is empty, remove it, free block %llu\n", leaf);
        bh = sb_find_get_block(inode->i_sb, leaf);
        ext4_forget(handle, 1, inode, bh, leaf);
-       ext4_free_blocks(handle, inode, leaf, 1);
+       ext4_free_blocks(handle, inode, leaf, 1, 1);
        return err;
 }
 
 /*
- * ext4_ext_calc_credits_for_insert:
- * This routine returns max. credits that the extent tree can consume.
- * It should be OK for low-performance paths like ->writepage()
- * To allow many writing processes to fit into a single transaction,
- * the caller should calculate credits under truncate_mutex and
- * pass the actual path.
+ * ext4_ext_calc_credits_for_single_extent:
+ * This routine returns max. credits that needed to insert an extent
+ * to the extent tree.
+ * When pass the actual path, the caller should calculate credits
+ * under i_data_sem.
  */
-int ext4_ext_calc_credits_for_insert(struct inode *inode,
+int ext4_ext_calc_credits_for_single_extent(struct inode *inode, int nrblocks,
                                                struct ext4_ext_path *path)
 {
-       int depth, needed;
-
        if (path) {
+               int depth = ext_depth(inode);
+               int ret = 0;
+
                /* probably there is space in leaf? */
-               depth = ext_depth(inode);
                if (le16_to_cpu(path[depth].p_hdr->eh_entries)
-                               < le16_to_cpu(path[depth].p_hdr->eh_max))
-                       return 1;
-       }
-
-       /*
-        * given 32-bit logical block (4294967296 blocks), max. tree
-        * can be 4 levels in depth -- 4 * 340^4 == 53453440000.
-        * Let's also add one more level for imbalance.
-        */
-       depth = 5;
+                               < le16_to_cpu(path[depth].p_hdr->eh_max)) {
 
-       /* allocation of new data block(s) */
-       needed = 2;
+                       /*
+                        *  There are some space in the leaf tree, no
+                        *  need to account for leaf block credit
+                        *
+                        *  bitmaps and block group descriptor blocks
+                        *  and other metadat blocks still need to be
+                        *  accounted.
+                        */
+                       /* 1 bitmap, 1 block group descriptor */
+                       ret = 2 + EXT4_META_TRANS_BLOCKS(inode->i_sb);
+               }
+       }
 
-       /*
-        * tree can be full, so it would need to grow in depth:
-        * we need one credit to modify old root, credits for
-        * new root will be added in split accounting
-        */
-       needed += 1;
+       return ext4_chunk_trans_blocks(inode, nrblocks);
+}
 
-       /*
-        * Index split can happen, we would need:
-        *    allocate intermediate indexes (bitmap + group)
-        *  + change two blocks at each level, but root (already included)
-        */
-       needed += (depth * 2) + (depth * 2);
+/*
+ * How many index/leaf blocks need to change/allocate to modify nrblocks?
+ *
+ * if nrblocks are fit in a single extent (chunk flag is 1), then
+ * in the worse case, each tree level index/leaf need to be changed
+ * if the tree split due to insert a new extent, then the old tree
+ * index/leaf need to be updated too
+ *
+ * If the nrblocks are discontiguous, they could cause
+ * the whole tree split more than once, but this is really rare.
+ */
+int ext4_ext_index_trans_blocks(struct inode *inode, int nrblocks, int chunk)
+{
+       int index;
+       int depth = ext_depth(inode);
 
-       /* any allocation modifies superblock */
-       needed += 1;
+       if (chunk)
+               index = depth * 2;
+       else
+               index = depth * 3;
 
-       return needed;
+       return index;
 }
 
 static int ext4_remove_blocks(handle_t *handle, struct inode *inode,
@@ -1617,8 +1917,10 @@ static int ext4_remove_blocks(handle_t *handle, struct inode *inode,
 {
        struct buffer_head *bh;
        unsigned short ee_len =  ext4_ext_get_actual_len(ex);
-       int i;
+       int i, metadata = 0;
 
+       if (S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode))
+               metadata = 1;
 #ifdef EXTENTS_STATS
        {
                struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
@@ -1647,7 +1949,7 @@ static int ext4_remove_blocks(handle_t *handle, struct inode *inode,
                        bh = sb_find_get_block(inode->i_sb, start + i);
                        ext4_forget(handle, 0, inode, bh, start + i);
                }
-               ext4_free_blocks(handle, inode, start, num);
+               ext4_free_blocks(handle, inode, start, num, metadata);
        } else if (from == le32_to_cpu(ex->ee_block)
                   && to <= le32_to_cpu(ex->ee_block) + ee_len - 1) {
                printk(KERN_INFO "strange request: removal %u-%u from %u:%u\n",
@@ -1722,22 +2024,22 @@ ext4_ext_rm_leaf(handle_t *handle, struct inode *inode,
                        BUG_ON(b != ex_ee_block + ex_ee_len - 1);
                }
 
-               /* at present, extent can't cross block group: */
-               /* leaf + bitmap + group desc + sb + inode */
-               credits = 5;
+               /*
+                * 3 for leaf, sb, and inode plus 2 (bmap and group
+                * descriptor) for each block group; assume two block
+                * groups plus ex_ee_len/blocks_per_block_group for
+                * the worst case
+                */
+               credits = 7 + 2*(ex_ee_len/EXT4_BLOCKS_PER_GROUP(inode->i_sb));
                if (ex == EXT_FIRST_EXTENT(eh)) {
                        correct_index = 1;
                        credits += (ext_depth(inode)) + 1;
                }
-#ifdef CONFIG_QUOTA
                credits += 2 * EXT4_QUOTA_TRANS_BLOCKS(inode->i_sb);
-#endif
 
-               handle = ext4_ext_journal_restart(handle, credits);
-               if (IS_ERR(handle)) {
-                       err = PTR_ERR(handle);
+               err = ext4_ext_journal_restart(handle, credits);
+               if (err)
                        goto out;
-               }
 
                err = ext4_ext_get_access(handle, inode, path + depth);
                if (err)
@@ -1750,7 +2052,7 @@ ext4_ext_rm_leaf(handle_t *handle, struct inode *inode,
                if (num == 0) {
                        /* this extent is removed; mark slot entirely unused */
                        ext4_ext_store_pblock(ex, 0);
-                       eh->eh_entries = cpu_to_le16(le16_to_cpu(eh->eh_entries)-1);
+                       le16_add_cpu(&eh->eh_entries, -1);
                }
 
                ex->ee_block = cpu_to_le32(block);
@@ -1827,7 +2129,7 @@ static int ext4_ext_remove_space(struct inode *inode, ext4_lblk_t start)
         * We start scanning from right side, freeing all the blocks
         * after i_size and walking into the tree depth-wise.
         */
-       path = kzalloc(sizeof(struct ext4_ext_path) * (depth + 1), GFP_KERNEL);
+       path = kzalloc(sizeof(struct ext4_ext_path) * (depth + 1), GFP_NOFS);
        if (path == NULL) {
                ext4_journal_stop(handle);
                return -ENOMEM;
@@ -1929,7 +2231,6 @@ static int ext4_ext_remove_space(struct inode *inode, ext4_lblk_t start)
                }
        }
 out:
-       ext4_ext_tree_changed(inode);
        ext4_ext_drop_refs(path);
        kfree(path);
        ext4_journal_stop(handle);
@@ -1946,8 +2247,8 @@ void ext4_ext_init(struct super_block *sb)
         * possible initialization would be here
         */
 
-       if (test_opt(sb, EXTENTS)) {
-               printk("EXT4-fs: file extents enabled");
+       if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_EXTENTS)) {
+               printk(KERN_INFO "EXT4-fs: file extents enabled");
 #ifdef AGGRESSIVE_TEST
                printk(", aggressive tests");
 #endif
@@ -1971,7 +2272,7 @@ void ext4_ext_init(struct super_block *sb)
  */
 void ext4_ext_release(struct super_block *sb)
 {
-       if (!test_opt(sb, EXTENTS))
+       if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_EXTENTS))
                return;
 
 #ifdef EXTENTS_STATS
@@ -1986,6 +2287,82 @@ void ext4_ext_release(struct super_block *sb)
 #endif
 }
 
+static void bi_complete(struct bio *bio, int error)
+{
+       complete((struct completion *)bio->bi_private);
+}
+
+/* FIXME!! we need to try to merge to left or right after zero-out  */
+static int ext4_ext_zeroout(struct inode *inode, struct ext4_extent *ex)
+{
+       int ret = -EIO;
+       struct bio *bio;
+       int blkbits, blocksize;
+       sector_t ee_pblock;
+       struct completion event;
+       unsigned int ee_len, len, done, offset;
+
+
+       blkbits   = inode->i_blkbits;
+       blocksize = inode->i_sb->s_blocksize;
+       ee_len    = ext4_ext_get_actual_len(ex);
+       ee_pblock = ext_pblock(ex);
+
+       /* convert ee_pblock to 512 byte sectors */
+       ee_pblock = ee_pblock << (blkbits - 9);
+
+       while (ee_len > 0) {
+
+               if (ee_len > BIO_MAX_PAGES)
+                       len = BIO_MAX_PAGES;
+               else
+                       len = ee_len;
+
+               bio = bio_alloc(GFP_NOIO, len);
+               if (!bio)
+                       return -ENOMEM;
+               bio->bi_sector = ee_pblock;
+               bio->bi_bdev   = inode->i_sb->s_bdev;
+
+               done = 0;
+               offset = 0;
+               while (done < len) {
+                       ret = bio_add_page(bio, ZERO_PAGE(0),
+                                                       blocksize, offset);
+                       if (ret != blocksize) {
+                               /*
+                                * We can't add any more pages because of
+                                * hardware limitations.  Start a new bio.
+                                */
+                               break;
+                       }
+                       done++;
+                       offset += blocksize;
+                       if (offset >= PAGE_CACHE_SIZE)
+                               offset = 0;
+               }
+
+               init_completion(&event);
+               bio->bi_private = &event;
+               bio->bi_end_io = bi_complete;
+               submit_bio(WRITE, bio);
+               wait_for_completion(&event);
+
+               if (test_bit(BIO_UPTODATE, &bio->bi_flags))
+                       ret = 0;
+               else {
+                       ret = -EIO;
+                       break;
+               }
+               bio_put(bio);
+               ee_len    -= done;
+               ee_pblock += done  << (blkbits - 9);
+       }
+       return ret;
+}
+
+#define EXT4_EXT_ZERO_LEN 7
+
 /*
  * This function is called by ext4_ext_get_blocks() if someone tries to write
  * to an uninitialized extent. It may result in splitting the uninitialized
@@ -2000,9 +2377,9 @@ static int ext4_ext_convert_to_initialized(handle_t *handle,
                                                struct inode *inode,
                                                struct ext4_ext_path *path,
                                                ext4_lblk_t iblock,
-                                               unsigned long max_blocks)
+                                               unsigned int max_blocks)
 {
-       struct ext4_extent *ex, newex;
+       struct ext4_extent *ex, newex, orig_ex;
        struct ext4_extent *ex1 = NULL;
        struct ext4_extent *ex2 = NULL;
        struct ext4_extent *ex3 = NULL;
@@ -2021,6 +2398,26 @@ static int ext4_ext_convert_to_initialized(handle_t *handle,
        allocated = ee_len - (iblock - ee_block);
        newblock = iblock - ee_block + ext_pblock(ex);
        ex2 = ex;
+       orig_ex.ee_block = ex->ee_block;
+       orig_ex.ee_len   = cpu_to_le16(ee_len);
+       ext4_ext_store_pblock(&orig_ex, ext_pblock(ex));
+
+       err = ext4_ext_get_access(handle, inode, path + depth);
+       if (err)
+               goto out;
+       /* If extent has less than 2*EXT4_EXT_ZERO_LEN zerout directly */
+       if (ee_len <= 2*EXT4_EXT_ZERO_LEN) {
+               err =  ext4_ext_zeroout(inode, &orig_ex);
+               if (err)
+                       goto fix_extent_len;
+               /* update the extent length and mark as initialized */
+               ex->ee_block = orig_ex.ee_block;
+               ex->ee_len   = orig_ex.ee_len;
+               ext4_ext_store_pblock(ex, ext_pblock(&orig_ex));
+               ext4_ext_dirty(handle, inode, path + depth);
+               /* zeroed the full extent */
+               return allocated;
+       }
 
        /* ex1: ee_block to iblock - 1 : uninitialized */
        if (iblock > ee_block) {
@@ -2039,33 +2436,144 @@ static int ext4_ext_convert_to_initialized(handle_t *handle,
        /* ex3: to ee_block + ee_len : uninitialised */
        if (allocated > max_blocks) {
                unsigned int newdepth;
+               /* If extent has less than EXT4_EXT_ZERO_LEN zerout directly */
+               if (allocated <= EXT4_EXT_ZERO_LEN) {
+                       /*
+                        * iblock == ee_block is handled by the zerouout
+                        * at the beginning.
+                        * Mark first half uninitialized.
+                        * Mark second half initialized and zero out the
+                        * initialized extent
+                        */
+                       ex->ee_block = orig_ex.ee_block;
+                       ex->ee_len   = cpu_to_le16(ee_len - allocated);
+                       ext4_ext_mark_uninitialized(ex);
+                       ext4_ext_store_pblock(ex, ext_pblock(&orig_ex));
+                       ext4_ext_dirty(handle, inode, path + depth);
+
+                       ex3 = &newex;
+                       ex3->ee_block = cpu_to_le32(iblock);
+                       ext4_ext_store_pblock(ex3, newblock);
+                       ex3->ee_len = cpu_to_le16(allocated);
+                       err = ext4_ext_insert_extent(handle, inode, path, ex3);
+                       if (err == -ENOSPC) {
+                               err =  ext4_ext_zeroout(inode, &orig_ex);
+                               if (err)
+                                       goto fix_extent_len;
+                               ex->ee_block = orig_ex.ee_block;
+                               ex->ee_len   = orig_ex.ee_len;
+                               ext4_ext_store_pblock(ex, ext_pblock(&orig_ex));
+                               ext4_ext_dirty(handle, inode, path + depth);
+                               /* blocks available from iblock */
+                               return allocated;
+
+                       } else if (err)
+                               goto fix_extent_len;
+
+                       /*
+                        * We need to zero out the second half because
+                        * an fallocate request can update file size and
+                        * converting the second half to initialized extent
+                        * implies that we can leak some junk data to user
+                        * space.
+                        */
+                       err =  ext4_ext_zeroout(inode, ex3);
+                       if (err) {
+                               /*
+                                * We should actually mark the
+                                * second half as uninit and return error
+                                * Insert would have changed the extent
+                                */
+                               depth = ext_depth(inode);
+                               ext4_ext_drop_refs(path);
+                               path = ext4_ext_find_extent(inode,
+                                                               iblock, path);
+                               if (IS_ERR(path)) {
+                                       err = PTR_ERR(path);
+                                       return err;
+                               }
+                               /* get the second half extent details */
+                               ex = path[depth].p_ext;
+                               err = ext4_ext_get_access(handle, inode,
+                                                               path + depth);
+                               if (err)
+                                       return err;
+                               ext4_ext_mark_uninitialized(ex);
+                               ext4_ext_dirty(handle, inode, path + depth);
+                               return err;
+                       }
+
+                       /* zeroed the second half */
+                       return allocated;
+               }
                ex3 = &newex;
                ex3->ee_block = cpu_to_le32(iblock + max_blocks);
                ext4_ext_store_pblock(ex3, newblock + max_blocks);
                ex3->ee_len = cpu_to_le16(allocated - max_blocks);
                ext4_ext_mark_uninitialized(ex3);
                err = ext4_ext_insert_extent(handle, inode, path, ex3);
-               if (err)
-                       goto out;
+               if (err == -ENOSPC) {
+                       err =  ext4_ext_zeroout(inode, &orig_ex);
+                       if (err)
+                               goto fix_extent_len;
+                       /* update the extent length and mark as initialized */
+                       ex->ee_block = orig_ex.ee_block;
+                       ex->ee_len   = orig_ex.ee_len;
+                       ext4_ext_store_pblock(ex, ext_pblock(&orig_ex));
+                       ext4_ext_dirty(handle, inode, path + depth);
+                       /* zeroed the full extent */
+                       /* blocks available from iblock */
+                       return allocated;
+
+               } else if (err)
+                       goto fix_extent_len;
                /*
                 * The depth, and hence eh & ex might change
                 * as part of the insert above.
                 */
                newdepth = ext_depth(inode);
-               if (newdepth != depth) {
-                       depth = newdepth;
-                       path = ext4_ext_find_extent(inode, iblock, NULL);
-                       if (IS_ERR(path)) {
-                               err = PTR_ERR(path);
-                               path = NULL;
-                               goto out;
-                       }
-                       eh = path[depth].p_hdr;
-                       ex = path[depth].p_ext;
-                       if (ex2 != &newex)
-                               ex2 = ex;
+               /*
+                * update the extent length after successful insert of the
+                * split extent
+                */
+               orig_ex.ee_len = cpu_to_le16(ee_len -
+                                               ext4_ext_get_actual_len(ex3));
+               depth = newdepth;
+               ext4_ext_drop_refs(path);
+               path = ext4_ext_find_extent(inode, iblock, path);
+               if (IS_ERR(path)) {
+                       err = PTR_ERR(path);
+                       goto out;
                }
+               eh = path[depth].p_hdr;
+               ex = path[depth].p_ext;
+               if (ex2 != &newex)
+                       ex2 = ex;
+
+               err = ext4_ext_get_access(handle, inode, path + depth);
+               if (err)
+                       goto out;
+
                allocated = max_blocks;
+
+               /* If extent has less than EXT4_EXT_ZERO_LEN and we are trying
+                * to insert a extent in the middle zerout directly
+                * otherwise give the extent a chance to merge to left
+                */
+               if (le16_to_cpu(orig_ex.ee_len) <= EXT4_EXT_ZERO_LEN &&
+                                                       iblock != ee_block) {
+                       err =  ext4_ext_zeroout(inode, &orig_ex);
+                       if (err)
+                               goto fix_extent_len;
+                       /* update the extent length and mark as initialized */
+                       ex->ee_block = orig_ex.ee_block;
+                       ex->ee_len   = orig_ex.ee_len;
+                       ext4_ext_store_pblock(ex, ext_pblock(&orig_ex));
+                       ext4_ext_dirty(handle, inode, path + depth);
+                       /* zero out the first half */
+                       /* blocks available from iblock */
+                       return allocated;
+               }
        }
        /*
         * If there was a change of depth as part of the
@@ -2084,9 +2592,6 @@ static int ext4_ext_convert_to_initialized(handle_t *handle,
        ex2->ee_len = cpu_to_le16(allocated);
        if (ex2 != ex)
                goto insert;
-       err = ext4_ext_get_access(handle, inode, path + depth);
-       if (err)
-               goto out;
        /*
         * New (initialized) extent starts from the first block
         * in the current extent. i.e., ex2 == ex
@@ -2125,31 +2630,71 @@ static int ext4_ext_convert_to_initialized(handle_t *handle,
        goto out;
 insert:
        err = ext4_ext_insert_extent(handle, inode, path, &newex);
+       if (err == -ENOSPC) {
+               err =  ext4_ext_zeroout(inode, &orig_ex);
+               if (err)
+                       goto fix_extent_len;
+               /* update the extent length and mark as initialized */
+               ex->ee_block = orig_ex.ee_block;
+               ex->ee_len   = orig_ex.ee_len;
+               ext4_ext_store_pblock(ex, ext_pblock(&orig_ex));
+               ext4_ext_dirty(handle, inode, path + depth);
+               /* zero out the first half */
+               return allocated;
+       } else if (err)
+               goto fix_extent_len;
 out:
        return err ? err : allocated;
+
+fix_extent_len:
+       ex->ee_block = orig_ex.ee_block;
+       ex->ee_len   = orig_ex.ee_len;
+       ext4_ext_store_pblock(ex, ext_pblock(&orig_ex));
+       ext4_ext_mark_uninitialized(ex);
+       ext4_ext_dirty(handle, inode, path + depth);
+       return err;
 }
 
+/*
+ * Block allocation/map/preallocation routine for extents based files
+ *
+ *
+ * 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)
+ *
+ * return > 0, number of of blocks already mapped/allocated
+ *          if create == 0 and these are pre-allocated blocks
+ *             buffer head is unmapped
+ *          otherwise blocks are mapped
+ *
+ * return = 0, if plain look up failed (blocks have not been allocated)
+ *          buffer head is unmapped
+ *
+ * return < 0, error case.
+ */
 int ext4_ext_get_blocks(handle_t *handle, struct inode *inode,
                        ext4_lblk_t iblock,
-                       unsigned long max_blocks, struct buffer_head *bh_result,
+                       unsigned int max_blocks, struct buffer_head *bh_result,
                        int create, int extend_disksize)
 {
        struct ext4_ext_path *path = NULL;
        struct ext4_extent_header *eh;
        struct ext4_extent newex, *ex;
-       ext4_fsblk_t goal, newblock;
-       int err = 0, depth, ret;
-       unsigned long allocated = 0;
+       ext4_fsblk_t newblock;
+       int err = 0, depth, ret, cache_type;
+       unsigned int allocated = 0;
+       struct ext4_allocation_request ar;
+       loff_t disksize;
 
        __clear_bit(BH_New, &bh_result->b_state);
-       ext_debug("blocks %u/%lu requested for inode %u\n",
+       ext_debug("blocks %u/%u requested for inode %u\n",
                        iblock, max_blocks, inode->i_ino);
-       mutex_lock(&EXT4_I(inode)->truncate_mutex);
 
        /* check in cache */
-       goal = ext4_ext_in_cache(inode, iblock, &newex);
-       if (goal) {
-               if (goal == EXT4_EXT_CACHE_GAP) {
+       cache_type = ext4_ext_in_cache(inode, iblock, &newex);
+       if (cache_type) {
+               if (cache_type == EXT4_EXT_CACHE_GAP) {
                        if (!create) {
                                /*
                                 * block isn't allocated yet and
@@ -2158,13 +2703,13 @@ int ext4_ext_get_blocks(handle_t *handle, struct inode *inode,
                                goto out2;
                        }
                        /* we should allocate requested block */
-               } else if (goal == EXT4_EXT_CACHE_EXTENT) {
+               } else if (cache_type == EXT4_EXT_CACHE_EXTENT) {
                        /* block is already allocated */
                        newblock = iblock
                                   - le32_to_cpu(newex.ee_block)
                                   + ext_pblock(&newex);
                        /* number of remaining blocks in the extent */
-                       allocated = le16_to_cpu(newex.ee_len) -
+                       allocated = ext4_ext_get_actual_len(&newex) -
                                        (iblock - le32_to_cpu(newex.ee_block));
                        goto out;
                } else {
@@ -2218,15 +2763,27 @@ int ext4_ext_get_blocks(handle_t *handle, struct inode *inode,
                        }
                        if (create == EXT4_CREATE_UNINITIALIZED_EXT)
                                goto out;
-                       if (!create)
+                       if (!create) {
+                               /*
+                                * We have blocks reserved already.  We
+                                * return allocated blocks so that delalloc
+                                * won't do block reservation for us.  But
+                                * the buffer head will be unmapped so that
+                                * a read from the block returns 0s.
+                                */
+                               if (allocated > max_blocks)
+                                       allocated = max_blocks;
+                               set_buffer_unwritten(bh_result);
                                goto out2;
+                       }
 
                        ret = ext4_ext_convert_to_initialized(handle, inode,
                                                                path, iblock,
                                                                max_blocks);
-                       if (ret <= 0)
+                       if (ret <= 0) {
+                               err = ret;
                                goto out2;
-                       else
+                       else
                                allocated = ret;
                        goto outnew;
                }
@@ -2245,14 +2802,18 @@ int ext4_ext_get_blocks(handle_t *handle, struct inode *inode,
                goto out2;
        }
        /*
-        * 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) && (!EXT4_I(inode)->i_block_alloc_info))
-               ext4_init_block_alloc_info(inode);
 
-       /* allocate new block */
-       goal = ext4_ext_find_goal(inode, path, iblock);
+       /* find neighbour allocated blocks */
+       ar.lleft = iblock;
+       err = ext4_ext_search_left(inode, path, &ar.lleft, &ar.pleft);
+       if (err)
+               goto out2;
+       ar.lright = iblock;
+       err = ext4_ext_search_right(inode, path, &ar.lright, &ar.pright);
+       if (err)
+               goto out2;
 
        /*
         * See if request is beyond maximum number of blocks we can have in
@@ -2272,35 +2833,55 @@ int ext4_ext_get_blocks(handle_t *handle, struct inode *inode,
        newex.ee_len = cpu_to_le16(max_blocks);
        err = ext4_ext_check_overlap(inode, &newex, path);
        if (err)
-               allocated = le16_to_cpu(newex.ee_len);
+               allocated = ext4_ext_get_actual_len(&newex);
        else
                allocated = max_blocks;
-       newblock = ext4_new_blocks(handle, inode, goal, &allocated, &err);
+
+       /* allocate new block */
+       ar.inode = inode;
+       ar.goal = ext4_ext_find_goal(inode, path, iblock);
+       ar.logical = iblock;
+       ar.len = allocated;
+       if (S_ISREG(inode->i_mode))
+               ar.flags = EXT4_MB_HINT_DATA;
+       else
+               /* disable in-core preallocation for non-regular files */
+               ar.flags = 0;
+       newblock = ext4_mb_new_blocks(handle, &ar, &err);
        if (!newblock)
                goto out2;
        ext_debug("allocate new block: goal %llu, found %llu/%lu\n",
-                       goal, newblock, allocated);
+                 ar.goal, newblock, allocated);
 
        /* try to insert new extent into found leaf and return */
        ext4_ext_store_pblock(&newex, newblock);
-       newex.ee_len = cpu_to_le16(allocated);
+       newex.ee_len = cpu_to_le16(ar.len);
        if (create == EXT4_CREATE_UNINITIALIZED_EXT)  /* Mark uninitialized */
                ext4_ext_mark_uninitialized(&newex);
        err = ext4_ext_insert_extent(handle, inode, path, &newex);
        if (err) {
                /* free data blocks we just allocated */
+               /* not a good idea to call discard here directly,
+                * but otherwise we'd need to call it every free() */
+               ext4_discard_preallocations(inode);
                ext4_free_blocks(handle, inode, ext_pblock(&newex),
-                                       le16_to_cpu(newex.ee_len));
+                                       ext4_ext_get_actual_len(&newex), 0);
                goto out2;
        }
 
-       if (extend_disksize && inode->i_size > EXT4_I(inode)->i_disksize)
-               EXT4_I(inode)->i_disksize = inode->i_size;
-
        /* previous routine could use block we allocated */
        newblock = ext_pblock(&newex);
+       allocated = ext4_ext_get_actual_len(&newex);
 outnew:
-       __set_bit(BH_New, &bh_result->b_state);
+       if (extend_disksize) {
+               disksize = ((loff_t) iblock + ar.len) << inode->i_blkbits;
+               if (disksize > i_size_read(inode))
+                       disksize = i_size_read(inode);
+               if (disksize > EXT4_I(inode)->i_disksize)
+                       EXT4_I(inode)->i_disksize = disksize;
+       }
+
+       set_buffer_new(bh_result);
 
        /* Cache only when it is _not_ an uninitialized extent */
        if (create != EXT4_CREATE_UNINITIALIZED_EXT)
@@ -2310,7 +2891,7 @@ out:
        if (allocated > max_blocks)
                allocated = max_blocks;
        ext4_ext_show_leaf(inode, path);
-       __set_bit(BH_Mapped, &bh_result->b_state);
+       set_buffer_mapped(bh_result);
        bh_result->b_bdev = inode->i_sb->s_bdev;
        bh_result->b_blocknr = newblock;
 out2:
@@ -2318,12 +2899,10 @@ out2:
                ext4_ext_drop_refs(path);
                kfree(path);
        }
-       mutex_unlock(&EXT4_I(inode)->truncate_mutex);
-
        return err ? err : allocated;
 }
 
-void ext4_ext_truncate(struct inode * inode, struct page *page)
+void ext4_ext_truncate(struct inode *inode)
 {
        struct address_space *mapping = inode->i_mapping;
        struct super_block *sb = inode->i_sb;
@@ -2334,31 +2913,27 @@ void ext4_ext_truncate(struct inode * inode, struct page *page)
        /*
         * probably first extent we're gonna free will be last in block
         */
-       err = ext4_writepage_trans_blocks(inode) + 3;
+       err = ext4_writepage_trans_blocks(inode);
        handle = ext4_journal_start(inode, err);
-       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;
-       }
 
-       if (page)
-               ext4_block_truncate_page(handle, page, mapping, inode->i_size);
+       if (inode->i_size & (sb->s_blocksize - 1))
+               ext4_block_truncate_page(handle, mapping, inode->i_size);
 
-       mutex_lock(&EXT4_I(inode)->truncate_mutex);
+       if (ext4_orphan_add(handle, inode))
+               goto out_stop;
+
+       down_write(&EXT4_I(inode)->i_data_sem);
        ext4_ext_invalidate_cache(inode);
 
+       ext4_discard_preallocations(inode);
+
        /*
         * TODO: optimization is possible here.
         * Probably we need not scan at all,
         * because page truncation is enough.
         */
-       if (ext4_orphan_add(handle, inode))
-               goto out_stop;
 
        /* we have to know where to truncate from in crash case */
        EXT4_I(inode)->i_disksize = inode->i_size;
@@ -2372,9 +2947,10 @@ void ext4_ext_truncate(struct inode * inode, struct page *page)
         * transaction synchronous.
         */
        if (IS_SYNC(inode))
-               handle->h_sync = 1;
+               ext4_handle_sync(handle);
 
 out_stop:
+       up_write(&EXT4_I(inode)->i_data_sem);
        /*
         * If this was a simple ftruncate() and the file will remain alive,
         * then we need to clear up the orphan record which we created above.
@@ -2385,29 +2961,32 @@ out_stop:
        if (inode->i_nlink)
                ext4_orphan_del(handle, inode);
 
-       mutex_unlock(&EXT4_I(inode)->truncate_mutex);
+       inode->i_mtime = inode->i_ctime = ext4_current_time(inode);
+       ext4_mark_inode_dirty(handle, inode);
        ext4_journal_stop(handle);
 }
 
-/*
- * ext4_ext_writepage_trans_blocks:
- * calculate max number of blocks we could modify
- * in order to allocate new block for an inode
- */
-int ext4_ext_writepage_trans_blocks(struct inode *inode, int num)
+static void ext4_falloc_update_inode(struct inode *inode,
+                               int mode, loff_t new_size, int update_ctime)
 {
-       int needed;
-
-       needed = ext4_ext_calc_credits_for_insert(inode, NULL);
-
-       /* caller wants to allocate num blocks, but note it includes sb */
-       needed = needed * num - (num - 1);
+       struct timespec now;
 
-#ifdef CONFIG_QUOTA
-       needed += 2 * EXT4_QUOTA_TRANS_BLOCKS(inode->i_sb);
-#endif
+       if (update_ctime) {
+               now = current_fs_time(inode->i_sb);
+               if (!timespec_equal(&inode->i_ctime, &now))
+                       inode->i_ctime = now;
+       }
+       /*
+        * Update only when preallocation was requested beyond
+        * the file size.
+        */
+       if (!(mode & FALLOC_FL_KEEP_SIZE)) {
+               if (new_size > i_size_read(inode))
+                       i_size_write(inode, new_size);
+               if (new_size > EXT4_I(inode)->i_disksize)
+                       ext4_update_i_disksize(inode, new_size);
+       }
 
-       return needed;
 }
 
 /*
@@ -2421,8 +3000,8 @@ long ext4_fallocate(struct inode *inode, int mode, loff_t offset, loff_t len)
 {
        handle_t *handle;
        ext4_lblk_t block;
-       unsigned long max_blocks;
-       ext4_fsblk_t nblocks = 0;
+       loff_t new_size;
+       unsigned int max_blocks;
        int ret = 0;
        int ret2 = 0;
        int retries = 0;
@@ -2441,14 +3020,17 @@ long ext4_fallocate(struct inode *inode, int mode, loff_t offset, loff_t len)
                return -ENODEV;
 
        block = offset >> blkbits;
+       /*
+        * We can't just convert len to max_blocks because
+        * If blocksize = 4096 offset = 3072 and len = 2048
+        */
        max_blocks = (EXT4_BLOCK_ALIGN(len + offset, blkbits) >> blkbits)
-                       - block;
-
+                                                       - block;
        /*
-        * credits to insert 1 extent into extent tree + buffers to be able to
-        * modify 1 super block, 1 block bitmap and 1 group descriptor.
+        * credits to insert 1 extent into extent tree
         */
-       credits = EXT4_DATA_TRANS_BLOCKS(inode->i_sb) + 3;
+       credits = ext4_chunk_trans_blocks(inode, max_blocks);
+       mutex_lock(&inode->i_mutex);
 retry:
        while (ret >= 0 && ret < max_blocks) {
                block = block + ret;
@@ -2458,79 +3040,180 @@ retry:
                        ret = PTR_ERR(handle);
                        break;
                }
-
-               ret = ext4_ext_get_blocks(handle, inode, block,
+               ret = ext4_get_blocks_wrap(handle, inode, block,
                                          max_blocks, &map_bh,
-                                         EXT4_CREATE_UNINITIALIZED_EXT, 0);
-               WARN_ON(ret <= 0);
+                                         EXT4_CREATE_UNINITIALIZED_EXT, 0, 0);
                if (ret <= 0) {
-                       ext4_error(inode->i_sb, "ext4_fallocate",
-                                   "ext4_ext_get_blocks returned error: "
-                                   "inode#%lu, block=%u, max_blocks=%lu",
+#ifdef EXT4FS_DEBUG
+                       WARN_ON(ret <= 0);
+                       printk(KERN_ERR "%s: ext4_ext_get_blocks "
+                                   "returned error inode#%lu, block=%u, "
+                                   "max_blocks=%u", __func__,
                                    inode->i_ino, block, max_blocks);
-                       ret = -EIO;
+#endif
                        ext4_mark_inode_dirty(handle, inode);
                        ret2 = ext4_journal_stop(handle);
                        break;
                }
-               if (ret > 0) {
-                       /* check wrap through sign-bit/zero here */
-                       if ((block + ret) < 0 || (block + ret) < block) {
-                               ret = -EIO;
-                               ext4_mark_inode_dirty(handle, inode);
-                               ret2 = ext4_journal_stop(handle);
-                               break;
-                       }
-                       if (buffer_new(&map_bh) && ((block + ret) >
-                           (EXT4_BLOCK_ALIGN(i_size_read(inode), blkbits)
-                           >> blkbits)))
-                                       nblocks = nblocks + ret;
-               }
-
-               /* Update ctime if new blocks get allocated */
-               if (nblocks) {
-                       struct timespec now;
-
-                       now = current_fs_time(inode->i_sb);
-                       if (!timespec_equal(&inode->i_ctime, &now))
-                               inode->i_ctime = now;
-               }
+               if ((block + ret) >= (EXT4_BLOCK_ALIGN(offset + len,
+                                               blkbits) >> blkbits))
+                       new_size = offset + len;
+               else
+                       new_size = (block + ret) << blkbits;
 
+               ext4_falloc_update_inode(inode, mode, new_size,
+                                               buffer_new(&map_bh));
                ext4_mark_inode_dirty(handle, inode);
                ret2 = ext4_journal_stop(handle);
                if (ret2)
                        break;
        }
-
-       if (ret == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries))
+       if (ret == -ENOSPC &&
+                       ext4_should_retry_alloc(inode->i_sb, &retries)) {
+               ret = 0;
                goto retry;
+       }
+       mutex_unlock(&inode->i_mutex);
+       return ret > 0 ? ret2 : ret;
+}
+
+/*
+ * Callback function called for each extent to gather FIEMAP information.
+ */
+static int ext4_ext_fiemap_cb(struct inode *inode, struct ext4_ext_path *path,
+                      struct ext4_ext_cache *newex, struct ext4_extent *ex,
+                      void *data)
+{
+       struct fiemap_extent_info *fieinfo = data;
+       unsigned long blksize_bits = inode->i_sb->s_blocksize_bits;
+       __u64   logical;
+       __u64   physical;
+       __u64   length;
+       __u32   flags = 0;
+       int     error;
+
+       logical =  (__u64)newex->ec_block << blksize_bits;
+
+       if (newex->ec_type == EXT4_EXT_CACHE_GAP) {
+               pgoff_t offset;
+               struct page *page;
+               struct buffer_head *bh = NULL;
+
+               offset = logical >> PAGE_SHIFT;
+               page = find_get_page(inode->i_mapping, offset);
+               if (!page || !page_has_buffers(page))
+                       return EXT_CONTINUE;
+
+               bh = page_buffers(page);
+
+               if (!bh)
+                       return EXT_CONTINUE;
+
+               if (buffer_delay(bh)) {
+                       flags |= FIEMAP_EXTENT_DELALLOC;
+                       page_cache_release(page);
+               } else {
+                       page_cache_release(page);
+                       return EXT_CONTINUE;
+               }
+       }
+
+       physical = (__u64)newex->ec_start << blksize_bits;
+       length =   (__u64)newex->ec_len << blksize_bits;
+
+       if (ex && ext4_ext_is_uninitialized(ex))
+               flags |= FIEMAP_EXTENT_UNWRITTEN;
 
        /*
-        * Time to update the file size.
-        * Update only when preallocation was requested beyond the file size.
+        * If this extent reaches EXT_MAX_BLOCK, it must be last.
+        *
+        * Or if ext4_ext_next_allocated_block is EXT_MAX_BLOCK,
+        * this also indicates no more allocated blocks.
+        *
+        * XXX this might miss a single-block extent at EXT_MAX_BLOCK
         */
-       if (!(mode & FALLOC_FL_KEEP_SIZE) &&
-           (offset + len) > i_size_read(inode)) {
-               if (ret > 0) {
-                       /*
-                        * if no error, we assume preallocation succeeded
-                        * completely
-                        */
-                       mutex_lock(&inode->i_mutex);
-                       i_size_write(inode, offset + len);
-                       EXT4_I(inode)->i_disksize = i_size_read(inode);
-                       mutex_unlock(&inode->i_mutex);
-               } else if (ret < 0 && nblocks) {
-                       /* Handle partial allocation scenario */
-                       loff_t newsize;
-
-                       mutex_lock(&inode->i_mutex);
-                       newsize  = (nblocks << blkbits) + i_size_read(inode);
-                       i_size_write(inode, EXT4_BLOCK_ALIGN(newsize, blkbits));
-                       EXT4_I(inode)->i_disksize = i_size_read(inode);
-                       mutex_unlock(&inode->i_mutex);
-               }
+       if (logical + length - 1 == EXT_MAX_BLOCK ||
+           ext4_ext_next_allocated_block(path) == EXT_MAX_BLOCK)
+               flags |= FIEMAP_EXTENT_LAST;
+
+       error = fiemap_fill_next_extent(fieinfo, logical, physical,
+                                       length, flags);
+       if (error < 0)
+               return error;
+       if (error == 1)
+               return EXT_BREAK;
+
+       return EXT_CONTINUE;
+}
+
+/* fiemap flags we can handle specified here */
+#define EXT4_FIEMAP_FLAGS      (FIEMAP_FLAG_SYNC|FIEMAP_FLAG_XATTR)
+
+static int ext4_xattr_fiemap(struct inode *inode,
+                               struct fiemap_extent_info *fieinfo)
+{
+       __u64 physical = 0;
+       __u64 length;
+       __u32 flags = FIEMAP_EXTENT_LAST;
+       int blockbits = inode->i_sb->s_blocksize_bits;
+       int error = 0;
+
+       /* in-inode? */
+       if (EXT4_I(inode)->i_state & EXT4_STATE_XATTR) {
+               struct ext4_iloc iloc;
+               int offset;     /* offset of xattr in inode */
+
+               error = ext4_get_inode_loc(inode, &iloc);
+               if (error)
+                       return error;
+               physical = iloc.bh->b_blocknr << blockbits;
+               offset = EXT4_GOOD_OLD_INODE_SIZE +
+                               EXT4_I(inode)->i_extra_isize;
+               physical += offset;
+               length = EXT4_SB(inode->i_sb)->s_inode_size - offset;
+               flags |= FIEMAP_EXTENT_DATA_INLINE;
+       } else { /* external block */
+               physical = EXT4_I(inode)->i_file_acl << blockbits;
+               length = inode->i_sb->s_blocksize;
+       }
+
+       if (physical)
+               error = fiemap_fill_next_extent(fieinfo, 0, physical,
+                                               length, flags);
+       return (error < 0 ? error : 0);
+}
+
+int ext4_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
+               __u64 start, __u64 len)
+{
+       ext4_lblk_t start_blk;
+       ext4_lblk_t len_blks;
+       int error = 0;
+
+       /* fallback to generic here if not in extents fmt */
+       if (!(EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL))
+               return generic_block_fiemap(inode, fieinfo, start, len,
+                       ext4_get_block);
+
+       if (fiemap_check_flags(fieinfo, EXT4_FIEMAP_FLAGS))
+               return -EBADR;
+
+       if (fieinfo->fi_flags & FIEMAP_FLAG_XATTR) {
+               error = ext4_xattr_fiemap(inode, fieinfo);
+       } else {
+               start_blk = start >> inode->i_sb->s_blocksize_bits;
+               len_blks = len >> inode->i_sb->s_blocksize_bits;
+
+               /*
+                * Walk the extent tree gathering extent information.
+                * ext4_ext_fiemap_cb will push extents back to user.
+                */
+               down_write(&EXT4_I(inode)->i_data_sem);
+               error = ext4_ext_walk_space(inode, start_blk, len_blks,
+                                         ext4_ext_fiemap_cb, fieinfo);
+               up_write(&EXT4_I(inode)->i_data_sem);
        }
 
-       return ret > 0 ? ret2 : ret;
+       return error;
 }
+