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| author | Amir Goldstein <amir73il@gmail.com> | 2023-08-16 11:18:15 +0200 |
|---|---|---|
| committer | Amir Goldstein <amir73il@gmail.com> | 2023-10-30 23:12:57 +0100 |
| commit | d08d3b3c2caf6c482703bbc5efaa7b9ae95dea20 (patch) | |
| tree | f2a2f3a802638ba7c3bb1f283cf6b0c8e764f521 /fs/overlayfs | |
| parent | ovl: add helper ovl_file_modified() (diff) | |
| download | linux-d08d3b3c2caf6c482703bbc5efaa7b9ae95dea20.tar.xz linux-d08d3b3c2caf6c482703bbc5efaa7b9ae95dea20.zip | |
ovl: split ovl_want_write() into two helpers
ovl_get_write_access() gets write access to upper mnt without taking
freeze protection on upper sb and ovl_start_write() only takes freeze
protection on upper sb.
These helpers will be used to breakup the large ovl_want_write() scope
during copy up into finer grained freeze protection scopes.
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Diffstat (limited to 'fs/overlayfs')
| -rw-r--r-- | fs/overlayfs/overlayfs.h | 4 | ||||
| -rw-r--r-- | fs/overlayfs/util.c | 26 |
2 files changed, 30 insertions, 0 deletions
diff --git a/fs/overlayfs/overlayfs.h b/fs/overlayfs/overlayfs.h index 9817b2dcb132..a22de83e0a9b 100644 --- a/fs/overlayfs/overlayfs.h +++ b/fs/overlayfs/overlayfs.h @@ -398,6 +398,10 @@ static inline bool ovl_open_flags_need_copy_up(int flags) } /* util.c */ +int ovl_get_write_access(struct dentry *dentry); +void ovl_put_write_access(struct dentry *dentry); +void ovl_start_write(struct dentry *dentry); +void ovl_end_write(struct dentry *dentry); int ovl_want_write(struct dentry *dentry); void ovl_drop_write(struct dentry *dentry); struct dentry *ovl_workdir(struct dentry *dentry); diff --git a/fs/overlayfs/util.c b/fs/overlayfs/util.c index 4a9e7efc90aa..80f20ca85344 100644 --- a/fs/overlayfs/util.c +++ b/fs/overlayfs/util.c @@ -17,12 +17,38 @@ #include <linux/ratelimit.h> #include "overlayfs.h" +/* Get write access to upper mnt - may fail if upper sb was remounted ro */ +int ovl_get_write_access(struct dentry *dentry) +{ + struct ovl_fs *ofs = OVL_FS(dentry->d_sb); + return mnt_get_write_access(ovl_upper_mnt(ofs)); +} + +/* Get write access to upper sb - may block if upper sb is frozen */ +void ovl_start_write(struct dentry *dentry) +{ + struct ovl_fs *ofs = OVL_FS(dentry->d_sb); + sb_start_write(ovl_upper_mnt(ofs)->mnt_sb); +} + int ovl_want_write(struct dentry *dentry) { struct ovl_fs *ofs = OVL_FS(dentry->d_sb); return mnt_want_write(ovl_upper_mnt(ofs)); } +void ovl_put_write_access(struct dentry *dentry) +{ + struct ovl_fs *ofs = OVL_FS(dentry->d_sb); + mnt_put_write_access(ovl_upper_mnt(ofs)); +} + +void ovl_end_write(struct dentry *dentry) +{ + struct ovl_fs *ofs = OVL_FS(dentry->d_sb); + sb_end_write(ovl_upper_mnt(ofs)->mnt_sb); +} + void ovl_drop_write(struct dentry *dentry) { struct ovl_fs *ofs = OVL_FS(dentry->d_sb); |