diff options
| author | Filipe Manana <fdmanana@suse.com> | 2024-05-03 19:10:06 +0200 |
|---|---|---|
| committer | David Sterba <dsterba@suse.com> | 2024-07-11 15:33:17 +0200 |
| commit | 068fc8f9141f503d2e7744208bb6d68a739ee53d (patch) | |
| tree | 3196966afecb53d542c3df00ffbc1d9cb44a8c54 /fs/btrfs/ioctl.c | |
| parent | btrfs: don't allocate file extent tree for non regular files (diff) | |
| download | linux-068fc8f9141f503d2e7744208bb6d68a739ee53d.tar.xz linux-068fc8f9141f503d2e7744208bb6d68a739ee53d.zip | |
btrfs: remove location key from struct btrfs_inode
Currently struct btrfs_inode has a key member, named "location", that is
either:
1) The key of the inode's item. In this case the objectid is the number
of the inode;
2) A key stored in a dir entry with a type of BTRFS_ROOT_ITEM_KEY, for
the case where we have a root that is a snapshot of a subvolume that
points to other subvolumes. In this case the objectid is the ID of
a subvolume inside the snapshotted parent subvolume.
The key is only used to lookup the inode item for the first case, while
for the second it's never used since it corresponds to directory stubs
created with new_simple_dir() and which are marked as dummy, so there's
no actual inode item to ever update. In the second case we only check
the key type at btrfs_ino() for 32 bits platforms and its objectid is
only needed for unlink.
Instead of using a key we can do fine with just the objectid, since we
can generate the key whenever we need it having only the objectid, as
in all use cases the type is always BTRFS_INODE_ITEM_KEY and the offset
is always 0.
So use only an objectid instead of a full key. This reduces the size of
struct btrfs_inode from 1048 bytes down to 1040 bytes on a release kernel.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Diffstat (limited to 'fs/btrfs/ioctl.c')
| -rw-r--r-- | fs/btrfs/ioctl.c | 8 |
1 files changed, 4 insertions, 4 deletions
diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c index 28df28e50ad9..79a5ccb27b92 100644 --- a/fs/btrfs/ioctl.c +++ b/fs/btrfs/ioctl.c @@ -1918,7 +1918,7 @@ static int btrfs_search_path_in_tree_user(struct mnt_idmap *idmap, { struct btrfs_fs_info *fs_info = BTRFS_I(inode)->root->fs_info; struct super_block *sb = inode->i_sb; - struct btrfs_key upper_limit = BTRFS_I(inode)->location; + u64 upper_limit = BTRFS_I(inode)->objectid; u64 treeid = btrfs_root_id(BTRFS_I(inode)->root); u64 dirid = args->dirid; unsigned long item_off; @@ -1944,7 +1944,7 @@ static int btrfs_search_path_in_tree_user(struct mnt_idmap *idmap, * If the bottom subvolume does not exist directly under upper_limit, * construct the path in from the bottom up. */ - if (dirid != upper_limit.objectid) { + if (dirid != upper_limit) { ptr = &args->path[BTRFS_INO_LOOKUP_USER_PATH_MAX - 1]; root = btrfs_get_fs_root(fs_info, treeid, true); @@ -2019,7 +2019,7 @@ static int btrfs_search_path_in_tree_user(struct mnt_idmap *idmap, goto out_put; } - if (key.offset == upper_limit.objectid) + if (key.offset == upper_limit) break; if (key.objectid == BTRFS_FIRST_FREE_OBJECTID) { ret = -EACCES; @@ -2140,7 +2140,7 @@ static int btrfs_ioctl_ino_lookup_user(struct file *file, void __user *argp) inode = file_inode(file); if (args->dirid == BTRFS_FIRST_FREE_OBJECTID && - BTRFS_I(inode)->location.objectid != BTRFS_FIRST_FREE_OBJECTID) { + BTRFS_I(inode)->objectid != BTRFS_FIRST_FREE_OBJECTID) { /* * The subvolume does not exist under fd with which this is * called |