Btrfs: keep track of the extents original block length

If we've written to a prealloc extent we need to know the original block len
for the extent.  We can't figure this out currently since ->block_len is
just set to the extent length.  So introduce ->orig_block_len so that we
know how many bytes were in the original extent for proper extent logging
that future patches will need.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>

diff --git a/fs/btrfs/extent_map.h b/fs/btrfs/extent_map.h
index 6792255..99a0dcb 100644 (file)
--- a/fs/btrfs/extent_map.h
+++ b/fs/btrfs/extent_map.h
@@ -24,6 +24,7 @@ struct extent_map {
        u64 mod_start;
        u64 mod_len;
        u64 orig_start;
+       u64 orig_block_len;
        u64 block_start;
        u64 block_len;
        u64 generation;

diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c
index 7f4654a..6810145 100644 (file)
--- a/fs/btrfs/file.c
+++ b/fs/btrfs/file.c
@@ -588,6 +588,8 @@ void btrfs_drop_extent_cache(struct inode *inode, u64 start, u64 end,
                                split->block_len = em->block_len;
                        else
                                split->block_len = split->len;
+                       split->orig_block_len = max(split->block_len,
+                                                   em->orig_block_len);
                        split->generation = gen;
                        split->bdev = em->bdev;
                        split->flags = flags;
@@ -609,6 +611,8 @@ void btrfs_drop_extent_cache(struct inode *inode, u64 start, u64 end,
                        split->flags = flags;
                        split->compress_type = em->compress_type;
                        split->generation = gen;
+                       split->orig_block_len = max(em->block_len,
+                                                   em->orig_block_len);
 
                        if (compressed) {
                                split->block_len = em->block_len;
@@ -1838,6 +1842,7 @@ out:
 
                hole_em->block_start = EXTENT_MAP_HOLE;
                hole_em->block_len = 0;
+               hole_em->orig_block_len = 0;
                hole_em->bdev = root->fs_info->fs_devices->latest_bdev;
                hole_em->compress_type = BTRFS_COMPRESS_NONE;
                hole_em->generation = trans->transid;

diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 7855aac..bfd59bc 100644 (file)
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -699,6 +699,7 @@ retry:
 
                em->block_start = ins.objectid;
                em->block_len = ins.offset;
+               em->orig_block_len = ins.offset;
                em->bdev = root->fs_info->fs_devices->latest_bdev;
                em->compress_type = async_extent->compress_type;
                set_bit(EXTENT_FLAG_PINNED, &em->flags);
@@ -886,6 +887,7 @@ static noinline int __cow_file_range(struct btrfs_trans_handle *trans,
 
                em->block_start = ins.objectid;
                em->block_len = ins.offset;
+               em->orig_block_len = ins.offset;
                em->bdev = root->fs_info->fs_devices->latest_bdev;
                set_bit(EXTENT_FLAG_PINNED, &em->flags);
 
@@ -1143,6 +1145,7 @@ static noinline int run_delalloc_nocow(struct inode *inode,
        u64 extent_offset;
        u64 disk_bytenr;
        u64 num_bytes;
+       u64 disk_num_bytes;
        int extent_type;
        int ret, err;
        int type;
@@ -1245,6 +1248,8 @@ next_slot:
                        extent_offset = btrfs_file_extent_offset(leaf, fi);
                        extent_end = found_key.offset +
                                btrfs_file_extent_num_bytes(leaf, fi);
+                       disk_num_bytes =
+                               btrfs_file_extent_disk_num_bytes(leaf, fi);
                        if (extent_end <= start) {
                                path->slots[0]++;
                                goto next_slot;
@@ -1319,6 +1324,7 @@ out_check:
                        em->len = num_bytes;
                        em->block_len = num_bytes;
                        em->block_start = disk_bytenr;
+                       em->orig_block_len = disk_num_bytes;
                        em->bdev = root->fs_info->fs_devices->latest_bdev;
                        set_bit(EXTENT_FLAG_PINNED, &em->flags);
                        set_bit(EXTENT_FLAG_PREALLOC, &em->flags);
@@ -3696,6 +3702,7 @@ int btrfs_cont_expand(struct inode *inode, loff_t oldsize, loff_t size)
 
                        hole_em->block_start = EXTENT_MAP_HOLE;
                        hole_em->block_len = 0;
+                       hole_em->orig_block_len = 0;
                        hole_em->bdev = root->fs_info->fs_devices->latest_bdev;
                        hole_em->compress_type = BTRFS_COMPRESS_NONE;
                        hole_em->generation = trans->transid;
@@ -5374,6 +5381,8 @@ again:
                em->len = extent_end - extent_start;
                em->orig_start = extent_start -
                                 btrfs_file_extent_offset(leaf, item);
+               em->orig_block_len = btrfs_file_extent_disk_num_bytes(leaf,
+                                                                     item);
                bytenr = btrfs_file_extent_disk_bytenr(leaf, item);
                if (bytenr == 0) {
                        em->block_start = EXTENT_MAP_HOLE;
@@ -5383,8 +5392,7 @@ again:
                        set_bit(EXTENT_FLAG_COMPRESSED, &em->flags);
                        em->compress_type = compress_type;
                        em->block_start = bytenr;
-                       em->block_len = btrfs_file_extent_disk_num_bytes(leaf,
-                                                                        item);
+                       em->block_len = em->orig_block_len;
                } else {
                        bytenr += btrfs_file_extent_offset(leaf, item);
                        em->block_start = bytenr;
@@ -5414,6 +5422,7 @@ again:
                em->start = extent_start + extent_offset;
                em->len = (copy_size + root->sectorsize - 1) &
                        ~((u64)root->sectorsize - 1);
+               em->orig_block_len = em->len;
                em->orig_start = EXTENT_MAP_INLINE;
                if (compress_type) {
                        set_bit(EXTENT_FLAG_COMPRESSED, &em->flags);
@@ -5721,6 +5730,7 @@ static struct extent_map *btrfs_new_extent_direct(struct inode *inode,
 
        em->block_start = ins.objectid;
        em->block_len = ins.offset;
+       em->orig_block_len = ins.offset;
        em->bdev = root->fs_info->fs_devices->latest_bdev;
 
        /*
@@ -5914,7 +5924,7 @@ static int lock_extent_direct(struct inode *inode, u64 lockstart, u64 lockend,
 static struct extent_map *create_pinned_em(struct inode *inode, u64 start,
                                           u64 len, u64 orig_start,
                                           u64 block_start, u64 block_len,
-                                          int type)
+                                          u64 orig_block_len, int type)
 {
        struct extent_map_tree *em_tree;
        struct extent_map *em;
@@ -5932,6 +5942,7 @@ static struct extent_map *create_pinned_em(struct inode *inode, u64 start,
        em->block_len = block_len;
        em->block_start = block_start;
        em->bdev = root->fs_info->fs_devices->latest_bdev;
+       em->orig_block_len = orig_block_len;
        set_bit(EXTENT_FLAG_PINNED, &em->flags);
        if (type == BTRFS_ORDERED_PREALLOC)
                set_bit(EXTENT_FLAG_PREALLOC, &em->flags);
@@ -6068,12 +6079,14 @@ static int btrfs_get_blocks_direct(struct inode *inode, sector_t iblock,
 
                if (can_nocow_odirect(trans, inode, start, len) == 1) {
                        u64 orig_start = em->start;
+                       u64 orig_block_len = em->orig_block_len;
 
                        if (type == BTRFS_ORDERED_PREALLOC) {
                                free_extent_map(em);
                                em = create_pinned_em(inode, start, len,
                                                       orig_start,
-                                                      block_start, len, type);
+                                                      block_start, len,
+                                                      orig_block_len, type);
                                if (IS_ERR(em)) {
                                        btrfs_end_transaction(trans, root);
                                        goto unlock_err;
@@ -7771,6 +7784,7 @@ static int __btrfs_prealloc_file_range(struct inode *inode, int mode,
                em->len = ins.offset;
                em->block_start = ins.objectid;
                em->block_len = ins.offset;
+               em->orig_block_len = ins.offset;
                em->bdev = root->fs_info->fs_devices->latest_bdev;
                set_bit(EXTENT_FLAG_PREALLOC, &em->flags);
                em->generation = trans->transid;