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| author | Miklos Szeredi <mszeredi@suse.cz> | 2014-10-24 00:14:35 +0200 |
|---|---|---|
| committer | Miklos Szeredi <mszeredi@suse.cz> | 2014-10-24 00:14:35 +0200 |
| commit | 4aa7c6346be395bdf776f82bbb2e3e2bc60bdd2b (patch) | |
| tree | a2135754a04370e7fcf7b867b0f4fbeaa58b3521 /Documentation/filesystems | |
| parent | Linux 3.18-rc1 (diff) | |
| download | linux-4aa7c6346be395bdf776f82bbb2e3e2bc60bdd2b.tar.xz linux-4aa7c6346be395bdf776f82bbb2e3e2bc60bdd2b.zip | |
vfs: add i_op->dentry_open()
Add a new inode operation i_op->dentry_open(). This is for stacked filesystems
that want to return a struct file from a different filesystem.
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Diffstat (limited to 'Documentation/filesystems')
| -rw-r--r-- | Documentation/filesystems/Locking | 2 | ||||
| -rw-r--r-- | Documentation/filesystems/vfs.txt | 7 |
2 files changed, 9 insertions, 0 deletions
diff --git a/Documentation/filesystems/Locking b/Documentation/filesystems/Locking index 94d93b1f8b53..b30753cbf431 100644 --- a/Documentation/filesystems/Locking +++ b/Documentation/filesystems/Locking @@ -67,6 +67,7 @@ prototypes: struct file *, unsigned open_flag, umode_t create_mode, int *opened); int (*tmpfile) (struct inode *, struct dentry *, umode_t); + int (*dentry_open)(struct dentry *, struct file *, const struct cred *); locking rules: all may block @@ -96,6 +97,7 @@ fiemap: no update_time: no atomic_open: yes tmpfile: no +dentry_open: no Additionally, ->rmdir(), ->unlink() and ->rename() have ->i_mutex on victim. diff --git a/Documentation/filesystems/vfs.txt b/Documentation/filesystems/vfs.txt index fceff7c00a3c..20bf204426ca 100644 --- a/Documentation/filesystems/vfs.txt +++ b/Documentation/filesystems/vfs.txt @@ -364,6 +364,7 @@ struct inode_operations { int (*atomic_open)(struct inode *, struct dentry *, struct file *, unsigned open_flag, umode_t create_mode, int *opened); int (*tmpfile) (struct inode *, struct dentry *, umode_t); + int (*dentry_open)(struct dentry *, struct file *, const struct cred *); }; Again, all methods are called without any locks being held, unless @@ -696,6 +697,12 @@ struct address_space_operations { but instead uses bmap to find out where the blocks in the file are and uses those addresses directly. + dentry_open: *WARNING: probably going away soon, do not use!* This is an + alternative to f_op->open(), the difference is that this method may open + a file not necessarily originating from the same filesystem as the one + i_op->open() was called on. It may be useful for stacking filesystems + which want to allow native I/O directly on underlying files. + invalidatepage: If a page has PagePrivate set, then invalidatepage will be called when part or all of the page is to be removed |