fs/affs: use ERR_CAST
[safe/jmp/linux-2.6] / fs / btrfs / file-item.c
index a3ad2ce..54a2550 100644 (file)
@@ -17,6 +17,7 @@
  */
 
 #include <linux/bio.h>
+#include <linux/slab.h>
 #include <linux/pagemap.h>
 #include <linux/highmem.h>
 #include "ctree.h"
 #include "transaction.h"
 #include "print-tree.h"
 
-#define MAX_CSUM_ITEMS(r,size) ((((BTRFS_LEAF_DATA_SIZE(r) - \
+#define MAX_CSUM_ITEMS(r, size) ((((BTRFS_LEAF_DATA_SIZE(r) - \
                                   sizeof(struct btrfs_item) * 2) / \
                                  size) - 1))
+
+#define MAX_ORDERED_SUM_BYTES(r) ((PAGE_SIZE - \
+                                  sizeof(struct btrfs_ordered_sum)) / \
+                                  sizeof(struct btrfs_sector_sum) * \
+                                  (r)->sectorsize - (r)->sectorsize)
+
 int btrfs_insert_file_extent(struct btrfs_trans_handle *trans,
                             struct btrfs_root *root,
                             u64 objectid, u64 pos,
@@ -46,6 +53,7 @@ int btrfs_insert_file_extent(struct btrfs_trans_handle *trans,
        file_key.offset = pos;
        btrfs_set_key_type(&file_key, BTRFS_EXTENT_DATA_KEY);
 
+       path->leave_spinning = 1;
        ret = btrfs_insert_empty_item(trans, root, path, &file_key,
                                      sizeof(*item));
        if (ret < 0)
@@ -140,6 +148,7 @@ int btrfs_lookup_file_extent(struct btrfs_trans_handle *trans,
        return ret;
 }
 
+
 int btrfs_lookup_bio_sums(struct btrfs_root *root, struct inode *inode,
                          struct bio *bio, u32 *dst)
 {
@@ -165,7 +174,7 @@ int btrfs_lookup_bio_sums(struct btrfs_root *root, struct inode *inode,
        WARN_ON(bio->bi_vcnt <= 0);
 
        disk_bytenr = (u64)bio->bi_sector << 9;
-       while(bio_index < bio->bi_vcnt) {
+       while (bio_index < bio->bi_vcnt) {
                offset = page_offset(bvec->bv_page) + bvec->bv_offset;
                ret = btrfs_find_ordered_sum(inode, offset, disk_bytenr, &sum);
                if (ret == 0)
@@ -185,9 +194,17 @@ int btrfs_lookup_bio_sums(struct btrfs_root *root, struct inode *inode,
                                if (ret == -ENOENT || ret == -EFBIG)
                                        ret = 0;
                                sum = 0;
-                               printk("no csum found for inode %lu start "
-                                      "%llu\n", inode->i_ino,
-                                      (unsigned long long)offset);
+                               if (BTRFS_I(inode)->root->root_key.objectid ==
+                                   BTRFS_DATA_RELOC_TREE_OBJECTID) {
+                                       set_extent_bits(io_tree, offset,
+                                               offset + bvec->bv_len - 1,
+                                               EXTENT_NODATASUM, GFP_NOFS);
+                               } else {
+                                       printk(KERN_INFO "btrfs no csum found "
+                                              "for inode %lu start %llu\n",
+                                              inode->i_ino,
+                                              (unsigned long long)offset);
+                               }
                                item = NULL;
                                btrfs_release_path(root, path);
                                goto found;
@@ -228,6 +245,114 @@ found:
        return 0;
 }
 
+int btrfs_lookup_csums_range(struct btrfs_root *root, u64 start, u64 end,
+                            struct list_head *list)
+{
+       struct btrfs_key key;
+       struct btrfs_path *path;
+       struct extent_buffer *leaf;
+       struct btrfs_ordered_sum *sums;
+       struct btrfs_sector_sum *sector_sum;
+       struct btrfs_csum_item *item;
+       unsigned long offset;
+       int ret;
+       size_t size;
+       u64 csum_end;
+       u16 csum_size = btrfs_super_csum_size(&root->fs_info->super_copy);
+
+       path = btrfs_alloc_path();
+       BUG_ON(!path);
+
+       key.objectid = BTRFS_EXTENT_CSUM_OBJECTID;
+       key.offset = start;
+       key.type = BTRFS_EXTENT_CSUM_KEY;
+
+       ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
+       if (ret < 0)
+               goto fail;
+       if (ret > 0 && path->slots[0] > 0) {
+               leaf = path->nodes[0];
+               btrfs_item_key_to_cpu(leaf, &key, path->slots[0] - 1);
+               if (key.objectid == BTRFS_EXTENT_CSUM_OBJECTID &&
+                   key.type == BTRFS_EXTENT_CSUM_KEY) {
+                       offset = (start - key.offset) >>
+                                root->fs_info->sb->s_blocksize_bits;
+                       if (offset * csum_size <
+                           btrfs_item_size_nr(leaf, path->slots[0] - 1))
+                               path->slots[0]--;
+               }
+       }
+
+       while (start <= end) {
+               leaf = path->nodes[0];
+               if (path->slots[0] >= btrfs_header_nritems(leaf)) {
+                       ret = btrfs_next_leaf(root, path);
+                       if (ret < 0)
+                               goto fail;
+                       if (ret > 0)
+                               break;
+                       leaf = path->nodes[0];
+               }
+
+               btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
+               if (key.objectid != BTRFS_EXTENT_CSUM_OBJECTID ||
+                   key.type != BTRFS_EXTENT_CSUM_KEY)
+                       break;
+
+               btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
+               if (key.offset > end)
+                       break;
+
+               if (key.offset > start)
+                       start = key.offset;
+
+               size = btrfs_item_size_nr(leaf, path->slots[0]);
+               csum_end = key.offset + (size / csum_size) * root->sectorsize;
+               if (csum_end <= start) {
+                       path->slots[0]++;
+                       continue;
+               }
+
+               csum_end = min(csum_end, end + 1);
+               item = btrfs_item_ptr(path->nodes[0], path->slots[0],
+                                     struct btrfs_csum_item);
+               while (start < csum_end) {
+                       size = min_t(size_t, csum_end - start,
+                                       MAX_ORDERED_SUM_BYTES(root));
+                       sums = kzalloc(btrfs_ordered_sum_size(root, size),
+                                       GFP_NOFS);
+                       BUG_ON(!sums);
+
+                       sector_sum = sums->sums;
+                       sums->bytenr = start;
+                       sums->len = size;
+
+                       offset = (start - key.offset) >>
+                               root->fs_info->sb->s_blocksize_bits;
+                       offset *= csum_size;
+
+                       while (size > 0) {
+                               read_extent_buffer(path->nodes[0],
+                                               &sector_sum->sum,
+                                               ((unsigned long)item) +
+                                               offset, csum_size);
+                               sector_sum->bytenr = start;
+
+                               size -= root->sectorsize;
+                               start += root->sectorsize;
+                               offset += csum_size;
+                               sector_sum++;
+                       }
+                       list_add_tail(&sums->list, list);
+               }
+               path->slots[0]++;
+       }
+       ret = 0;
+fail:
+       btrfs_free_path(path);
+       return ret;
+}
+
 int btrfs_csum_one_bio(struct btrfs_root *root, struct inode *inode,
                       struct bio *bio, u64 file_start, int contig)
 {
@@ -261,7 +386,7 @@ int btrfs_csum_one_bio(struct btrfs_root *root, struct inode *inode,
        BUG_ON(!ordered);
        sums->bytenr = ordered->start;
 
-       while(bio_index < bio->bi_vcnt) {
+       while (bio_index < bio->bi_vcnt) {
                if (!contig)
                        offset = page_offset(bvec->bv_page) + bvec->bv_offset;
 
@@ -310,6 +435,184 @@ int btrfs_csum_one_bio(struct btrfs_root *root, struct inode *inode,
        return 0;
 }
 
+/*
+ * helper function for csum removal, this expects the
+ * key to describe the csum pointed to by the path, and it expects
+ * the csum to overlap the range [bytenr, len]
+ *
+ * The csum should not be entirely contained in the range and the
+ * range should not be entirely contained in the csum.
+ *
+ * This calls btrfs_truncate_item with the correct args based on the
+ * overlap, and fixes up the key as required.
+ */
+static noinline int truncate_one_csum(struct btrfs_trans_handle *trans,
+                                     struct btrfs_root *root,
+                                     struct btrfs_path *path,
+                                     struct btrfs_key *key,
+                                     u64 bytenr, u64 len)
+{
+       struct extent_buffer *leaf;
+       u16 csum_size =
+               btrfs_super_csum_size(&root->fs_info->super_copy);
+       u64 csum_end;
+       u64 end_byte = bytenr + len;
+       u32 blocksize_bits = root->fs_info->sb->s_blocksize_bits;
+       int ret;
+
+       leaf = path->nodes[0];
+       csum_end = btrfs_item_size_nr(leaf, path->slots[0]) / csum_size;
+       csum_end <<= root->fs_info->sb->s_blocksize_bits;
+       csum_end += key->offset;
+
+       if (key->offset < bytenr && csum_end <= end_byte) {
+               /*
+                *         [ bytenr - len ]
+                *         [   ]
+                *   [csum     ]
+                *   A simple truncate off the end of the item
+                */
+               u32 new_size = (bytenr - key->offset) >> blocksize_bits;
+               new_size *= csum_size;
+               ret = btrfs_truncate_item(trans, root, path, new_size, 1);
+               BUG_ON(ret);
+       } else if (key->offset >= bytenr && csum_end > end_byte &&
+                  end_byte > key->offset) {
+               /*
+                *         [ bytenr - len ]
+                *                 [ ]
+                *                 [csum     ]
+                * we need to truncate from the beginning of the csum
+                */
+               u32 new_size = (csum_end - end_byte) >> blocksize_bits;
+               new_size *= csum_size;
+
+               ret = btrfs_truncate_item(trans, root, path, new_size, 0);
+               BUG_ON(ret);
+
+               key->offset = end_byte;
+               ret = btrfs_set_item_key_safe(trans, root, path, key);
+               BUG_ON(ret);
+       } else {
+               BUG();
+       }
+       return 0;
+}
+
+/*
+ * deletes the csum items from the csum tree for a given
+ * range of bytes.
+ */
+int btrfs_del_csums(struct btrfs_trans_handle *trans,
+                   struct btrfs_root *root, u64 bytenr, u64 len)
+{
+       struct btrfs_path *path;
+       struct btrfs_key key;
+       u64 end_byte = bytenr + len;
+       u64 csum_end;
+       struct extent_buffer *leaf;
+       int ret;
+       u16 csum_size =
+               btrfs_super_csum_size(&root->fs_info->super_copy);
+       int blocksize_bits = root->fs_info->sb->s_blocksize_bits;
+
+       root = root->fs_info->csum_root;
+
+       path = btrfs_alloc_path();
+
+       while (1) {
+               key.objectid = BTRFS_EXTENT_CSUM_OBJECTID;
+               key.offset = end_byte - 1;
+               key.type = BTRFS_EXTENT_CSUM_KEY;
+
+               path->leave_spinning = 1;
+               ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
+               if (ret > 0) {
+                       if (path->slots[0] == 0)
+                               goto out;
+                       path->slots[0]--;
+               }
+               leaf = path->nodes[0];
+               btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
+
+               if (key.objectid != BTRFS_EXTENT_CSUM_OBJECTID ||
+                   key.type != BTRFS_EXTENT_CSUM_KEY) {
+                       break;
+               }
+
+               if (key.offset >= end_byte)
+                       break;
+
+               csum_end = btrfs_item_size_nr(leaf, path->slots[0]) / csum_size;
+               csum_end <<= blocksize_bits;
+               csum_end += key.offset;
+
+               /* this csum ends before we start, we're done */
+               if (csum_end <= bytenr)
+                       break;
+
+               /* delete the entire item, it is inside our range */
+               if (key.offset >= bytenr && csum_end <= end_byte) {
+                       ret = btrfs_del_item(trans, root, path);
+                       BUG_ON(ret);
+                       if (key.offset == bytenr)
+                               break;
+               } else if (key.offset < bytenr && csum_end > end_byte) {
+                       unsigned long offset;
+                       unsigned long shift_len;
+                       unsigned long item_offset;
+                       /*
+                        *        [ bytenr - len ]
+                        *     [csum                ]
+                        *
+                        * Our bytes are in the middle of the csum,
+                        * we need to split this item and insert a new one.
+                        *
+                        * But we can't drop the path because the
+                        * csum could change, get removed, extended etc.
+                        *
+                        * The trick here is the max size of a csum item leaves
+                        * enough room in the tree block for a single
+                        * item header.  So, we split the item in place,
+                        * adding a new header pointing to the existing
+                        * bytes.  Then we loop around again and we have
+                        * a nicely formed csum item that we can neatly
+                        * truncate.
+                        */
+                       offset = (bytenr - key.offset) >> blocksize_bits;
+                       offset *= csum_size;
+
+                       shift_len = (len >> blocksize_bits) * csum_size;
+
+                       item_offset = btrfs_item_ptr_offset(leaf,
+                                                           path->slots[0]);
+
+                       memset_extent_buffer(leaf, 0, item_offset + offset,
+                                            shift_len);
+                       key.offset = bytenr;
+
+                       /*
+                        * btrfs_split_item returns -EAGAIN when the
+                        * item changed size or key
+                        */
+                       ret = btrfs_split_item(trans, root, path, &key, offset);
+                       BUG_ON(ret && ret != -EAGAIN);
+
+                       key.offset = end_byte - 1;
+               } else {
+                       ret = truncate_one_csum(trans, root, path,
+                                               &key, bytenr, len);
+                       BUG_ON(ret);
+                       if (key.offset < bytenr)
+                               break;
+               }
+               btrfs_release_path(root, path);
+       }
+out:
+       btrfs_free_path(path);
+       return 0;
+}
+
 int btrfs_csum_file_blocks(struct btrfs_trans_handle *trans,
                           struct btrfs_root *root,
                           struct btrfs_ordered_sum *sums)
@@ -396,28 +699,39 @@ again:
                                csum_size, 1);
        if (ret < 0)
                goto fail_unlock;
-       if (ret == 0) {
-               BUG();
-       }
-       if (path->slots[0] == 0) {
-               goto insert;
+
+       if (ret > 0) {
+               if (path->slots[0] == 0)
+                       goto insert;
+               path->slots[0]--;
        }
-       path->slots[0]--;
+
        leaf = path->nodes[0];
        btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
        csum_offset = (bytenr - found_key.offset) >>
                        root->fs_info->sb->s_blocksize_bits;
+
        if (btrfs_key_type(&found_key) != BTRFS_EXTENT_CSUM_KEY ||
            found_key.objectid != BTRFS_EXTENT_CSUM_OBJECTID ||
            csum_offset >= MAX_CSUM_ITEMS(root, csum_size)) {
                goto insert;
        }
+
        if (csum_offset >= btrfs_item_size_nr(leaf, path->slots[0]) /
            csum_size) {
                u32 diff = (csum_offset + 1) * csum_size;
+
+               /*
+                * is the item big enough already?  we dropped our lock
+                * before and need to recheck
+                */
+               if (diff < btrfs_item_size_nr(leaf, path->slots[0]))
+                       goto csum;
+
                diff = diff - btrfs_item_size_nr(leaf, path->slots[0]);
                if (diff != csum_size)
                        goto insert;
+
                ret = btrfs_extend_item(trans, root, path, diff);
                BUG_ON(ret);
                goto csum;
@@ -431,7 +745,7 @@ insert:
                u64 next_sector = sector_sum->bytenr;
                struct btrfs_sector_sum *next = sector_sum + 1;
 
-               while(tmp < sums->len) {
+               while (tmp < sums->len) {
                        if (next_sector + root->sectorsize != next->bytenr)
                                break;
                        tmp += root->sectorsize;
@@ -446,8 +760,10 @@ insert:
        } else {
                ins_size = csum_size;
        }
+       path->leave_spinning = 1;
        ret = btrfs_insert_empty_item(trans, root, path, &file_key,
                                      ins_size);
+       path->leave_spinning = 0;
        if (ret < 0)
                goto fail_unlock;
        if (ret != 0) {
@@ -465,7 +781,6 @@ found:
        item_end = (struct btrfs_csum_item *)((unsigned char *)item_end +
                                      btrfs_item_size_nr(leaf, path->slots[0]));
        eb_token = NULL;
-       cond_resched();
 next_sector:
 
        if (!eb_token ||
@@ -506,9 +821,9 @@ next_sector:
                eb_token = NULL;
        }
        btrfs_mark_buffer_dirty(path->nodes[0]);
-       cond_resched();
        if (total_bytes < sums->len) {
                btrfs_release_path(root, path);
+               cond_resched();
                goto again;
        }
 out:
@@ -518,30 +833,3 @@ out:
 fail_unlock:
        goto out;
 }
-
-int btrfs_csum_truncate(struct btrfs_trans_handle *trans,
-                       struct btrfs_root *root, struct btrfs_path *path,
-                       u64 isize)
-{
-       struct btrfs_key key;
-       struct extent_buffer *leaf = path->nodes[0];
-       int slot = path->slots[0];
-       int ret;
-       u32 new_item_size;
-       u64 new_item_span;
-       u64 blocks;
-
-       btrfs_item_key_to_cpu(leaf, &key, slot);
-       if (isize <= key.offset)
-               return 0;
-       new_item_span = isize - key.offset;
-       blocks = (new_item_span + root->sectorsize - 1) >>
-               root->fs_info->sb->s_blocksize_bits;
-       new_item_size = blocks *
-               btrfs_super_csum_size(&root->fs_info->super_copy);
-       if (new_item_size >= btrfs_item_size_nr(leaf, slot))
-               return 0;
-       ret = btrfs_truncate_item(trans, root, path, new_item_size, 1);
-       BUG_ON(ret);
-       return ret;
-}