From: Chris Mason Date: Fri, 18 Jul 2008 10:17:13 +0000 (-0400) Subject: Btrfs: Handle data checksumming on bios that span multiple ordered extents X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=3edf7d33f4edb1e4a9bb0a4c0a84d95fb4d22a09;p=openwrt%2Fstaging%2Fblogic.git Btrfs: Handle data checksumming on bios that span multiple ordered extents Data checksumming is done right before the bio is sent down the IO stack, which means a single bio might span more than one ordered extent. In this case, the checksumming data is split between two ordered extents. Signed-off-by: Chris Mason --- diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h index acbce542d291..96ab2797c09a 100644 --- a/fs/btrfs/ctree.h +++ b/fs/btrfs/ctree.h @@ -1579,8 +1579,8 @@ int btrfs_lookup_file_extent(struct btrfs_trans_handle *trans, int btrfs_csum_file_blocks(struct btrfs_trans_handle *trans, struct btrfs_root *root, struct inode *inode, struct btrfs_ordered_sum *sums); -int btrfs_csum_one_bio(struct btrfs_root *root, - struct bio *bio, struct btrfs_ordered_sum **sums_ret); +int btrfs_csum_one_bio(struct btrfs_root *root, struct inode *inode, + struct bio *bio); struct btrfs_csum_item *btrfs_lookup_csum(struct btrfs_trans_handle *trans, struct btrfs_root *root, struct btrfs_path *path, diff --git a/fs/btrfs/file-item.c b/fs/btrfs/file-item.c index 345caf8ff516..e02f1e5acb0a 100644 --- a/fs/btrfs/file-item.c +++ b/fs/btrfs/file-item.c @@ -134,26 +134,53 @@ int btrfs_lookup_file_extent(struct btrfs_trans_handle *trans, return ret; } -int btrfs_csum_one_bio(struct btrfs_root *root, - struct bio *bio, struct btrfs_ordered_sum **sums_ret) +int btrfs_csum_one_bio(struct btrfs_root *root, struct inode *inode, + struct bio *bio) { struct btrfs_ordered_sum *sums; struct btrfs_sector_sum *sector_sum; + struct btrfs_ordered_extent *ordered; char *data; struct bio_vec *bvec = bio->bi_io_vec; int bio_index = 0; + unsigned long total_bytes = 0; + unsigned long this_sum_bytes = 0; + u64 offset; WARN_ON(bio->bi_vcnt <= 0); sums = kzalloc(btrfs_ordered_sum_size(root, bio->bi_size), GFP_NOFS); if (!sums) return -ENOMEM; - *sums_ret = sums; + sector_sum = &sums->sums; - sums->file_offset = page_offset(bvec->bv_page); + sums->file_offset = page_offset(bvec->bv_page) + bvec->bv_offset; sums->len = bio->bi_size; INIT_LIST_HEAD(&sums->list); + ordered = btrfs_lookup_ordered_extent(inode, sums->file_offset); + BUG_ON(!ordered); while(bio_index < bio->bi_vcnt) { + offset = page_offset(bvec->bv_page) + bvec->bv_offset; + if (offset >= ordered->file_offset + ordered->len) { + unsigned long bytes_left; + sums->len = this_sum_bytes; + this_sum_bytes = 0; + btrfs_add_ordered_sum(inode, ordered, sums); + btrfs_put_ordered_extent(ordered); + + bytes_left = bio->bi_size - total_bytes; + + sums = kzalloc(btrfs_ordered_sum_size(root, bytes_left), + GFP_NOFS); + BUG_ON(!sums); + sector_sum = &sums->sums; + sums->len = bytes_left; + sums->file_offset = offset; + ordered = btrfs_lookup_ordered_extent(inode, + sums->file_offset); + BUG_ON(!ordered); + } + data = kmap_atomic(bvec->bv_page, KM_USER0); sector_sum->sum = ~(u32)0; sector_sum->sum = btrfs_csum_data(root, @@ -165,10 +192,18 @@ int btrfs_csum_one_bio(struct btrfs_root *root, (char *)§or_sum->sum); sector_sum->offset = page_offset(bvec->bv_page) + bvec->bv_offset; + sector_sum++; bio_index++; + total_bytes += bvec->bv_len; + this_sum_bytes += bvec->bv_len; bvec++; } + btrfs_add_ordered_sum(inode, ordered, sums); + btrfs_put_ordered_extent(ordered); + if (total_bytes != bio->bi_size) { +printk("warning, total bytes %lu bio size %u\n", total_bytes, bio->bi_size); + } return 0; } diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index f37e09e724f7..4d729d90d2b8 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -351,12 +351,8 @@ int __btrfs_submit_bio_hook(struct inode *inode, int rw, struct bio *bio, { struct btrfs_root *root = BTRFS_I(inode)->root; int ret = 0; - struct btrfs_ordered_sum *sums; - ret = btrfs_csum_one_bio(root, bio, &sums); - BUG_ON(ret); - - ret = btrfs_add_ordered_sum(inode, sums); + ret = btrfs_csum_one_bio(root, inode, bio); BUG_ON(ret); return btrfs_map_bio(root, rw, bio, mirror_num, 1); diff --git a/fs/btrfs/ordered-data.c b/fs/btrfs/ordered-data.c index 230fd3ca6b2c..1ddb7bceea99 100644 --- a/fs/btrfs/ordered-data.c +++ b/fs/btrfs/ordered-data.c @@ -186,22 +186,17 @@ int btrfs_add_ordered_extent(struct inode *inode, u64 file_offset, /* * Add a struct btrfs_ordered_sum into the list of checksums to be inserted - * when an ordered extent is finished. + * when an ordered extent is finished. If the list covers more than one + * ordered extent, it is split across multiples. */ -int btrfs_add_ordered_sum(struct inode *inode, struct btrfs_ordered_sum *sum) +int btrfs_add_ordered_sum(struct inode *inode, + struct btrfs_ordered_extent *entry, + struct btrfs_ordered_sum *sum) { struct btrfs_ordered_inode_tree *tree; - struct rb_node *node; - struct btrfs_ordered_extent *entry; tree = &BTRFS_I(inode)->ordered_tree; mutex_lock(&tree->mutex); - node = tree_search(tree, sum->file_offset); - BUG_ON(!node); - - entry = rb_entry(node, struct btrfs_ordered_extent, rb_node); - BUG_ON(!offset_in_entry(entry, sum->file_offset)); - list_add_tail(&sum->list, &entry->list); mutex_unlock(&tree->mutex); return 0; @@ -524,8 +519,10 @@ int btrfs_find_ordered_sum(struct inode *inode, u64 offset, u32 *sum) struct btrfs_ordered_extent *ordered; struct btrfs_ordered_inode_tree *tree = &BTRFS_I(inode)->ordered_tree; struct list_head *cur; + unsigned long num_sectors; + unsigned long i; + u32 sectorsize = BTRFS_I(inode)->root->sectorsize; int ret = 1; - int index; ordered = btrfs_lookup_ordered_extent(inode, offset); if (!ordered) @@ -534,14 +531,17 @@ int btrfs_find_ordered_sum(struct inode *inode, u64 offset, u32 *sum) mutex_lock(&tree->mutex); list_for_each_prev(cur, &ordered->list) { ordered_sum = list_entry(cur, struct btrfs_ordered_sum, list); - if (offset >= ordered_sum->file_offset && - offset < ordered_sum->file_offset + ordered_sum->len) { - index = (offset - ordered_sum->file_offset) / - BTRFS_I(inode)->root->sectorsize;; + if (offset >= ordered_sum->file_offset) { + num_sectors = ordered_sum->len / sectorsize; sector_sums = &ordered_sum->sums; - *sum = sector_sums[index].sum; - ret = 0; - goto out; + for (i = 0; i < num_sectors; i++) { + if (sector_sums[i].offset == offset) { +printk("find ordered sum inode %lu offset %Lu\n", inode->i_ino, offset); + *sum = sector_sums[i].sum; + ret = 0; + goto out; + } + } } } out: diff --git a/fs/btrfs/ordered-data.h b/fs/btrfs/ordered-data.h index 98f491d1022b..1794efd13ca3 100644 --- a/fs/btrfs/ordered-data.h +++ b/fs/btrfs/ordered-data.h @@ -39,7 +39,11 @@ struct btrfs_sector_sum { struct btrfs_ordered_sum { u64 file_offset; - u64 len; + /* + * this is the length in bytes covered by the sums array below. + * But, the sums array may not be contiguous in the file. + */ + unsigned long len; struct list_head list; /* last field is a variable length array of btrfs_sector_sums */ struct btrfs_sector_sum sums; @@ -95,6 +99,7 @@ static inline int btrfs_ordered_sum_size(struct btrfs_root *root, u64 bytes) { unsigned long num_sectors = (bytes + root->sectorsize - 1) / root->sectorsize; + num_sectors++; return sizeof(struct btrfs_ordered_sum) + num_sectors * sizeof(struct btrfs_sector_sum); } @@ -114,7 +119,9 @@ int btrfs_dec_test_ordered_pending(struct inode *inode, u64 file_offset, u64 io_size); int btrfs_add_ordered_extent(struct inode *inode, u64 file_offset, u64 start, u64 len); -int btrfs_add_ordered_sum(struct inode *inode, struct btrfs_ordered_sum *sum); +int btrfs_add_ordered_sum(struct inode *inode, + struct btrfs_ordered_extent *entry, + struct btrfs_ordered_sum *sum); struct btrfs_ordered_extent *btrfs_lookup_ordered_extent(struct inode *inode, u64 file_offset); void btrfs_start_ordered_extent(struct inode *inode,