diff options
Diffstat (limited to 'Documentation')
| -rw-r--r-- | Documentation/filesystems/Locking | 2 | ||||
| -rw-r--r-- | Documentation/filesystems/porting | 20 | ||||
| -rw-r--r-- | Documentation/filesystems/vfs.txt | 18 |
3 files changed, 31 insertions, 9 deletions
diff --git a/Documentation/filesystems/Locking b/Documentation/filesystems/Locking index 37bf0a9de75c..7cca82ed2ed1 100644 --- a/Documentation/filesystems/Locking +++ b/Documentation/filesystems/Locking @@ -64,7 +64,7 @@ prototypes: void (*update_time)(struct inode *, struct timespec *, int); int (*atomic_open)(struct inode *, struct dentry *, struct file *, unsigned open_flag, - umode_t create_mode, int *opened); + umode_t create_mode); int (*tmpfile) (struct inode *, struct dentry *, umode_t); locking rules: diff --git a/Documentation/filesystems/porting b/Documentation/filesystems/porting index 17bb4dc28fae..7b7b845c490a 100644 --- a/Documentation/filesystems/porting +++ b/Documentation/filesystems/porting @@ -602,3 +602,23 @@ in your dentry operations instead. dentry separately, and it now has request_mask and query_flags arguments to specify the fields and sync type requested by statx. Filesystems not supporting any statx-specific features may ignore the new arguments. +-- +[mandatory] + ->atomic_open() calling conventions have changed. Gone is int *opened, + along with FILE_OPENED/FILE_CREATED. In place of those we have + FMODE_OPENED/FMODE_CREATED, set in file->f_mode. Additionally, return + value for 'called finish_no_open(), open it yourself' case has become + 0, not 1. Since finish_no_open() itself is returning 0 now, that part + does not need any changes in ->atomic_open() instances. +-- +[mandatory] + alloc_file() has become static now; two wrappers are to be used instead. + alloc_file_pseudo(inode, vfsmount, name, flags, ops) is for the cases + when dentry needs to be created; that's the majority of old alloc_file() + users. Calling conventions: on success a reference to new struct file + is returned and callers reference to inode is subsumed by that. On + failure, ERR_PTR() is returned and no caller's references are affected, + so the caller needs to drop the inode reference it held. + alloc_file_clone(file, flags, ops) does not affect any caller's references. + On success you get a new struct file sharing the mount/dentry with the + original, on failure - ERR_PTR(). diff --git a/Documentation/filesystems/vfs.txt b/Documentation/filesystems/vfs.txt index f608180ad59d..85907d5b9c2c 100644 --- a/Documentation/filesystems/vfs.txt +++ b/Documentation/filesystems/vfs.txt @@ -386,7 +386,7 @@ struct inode_operations { ssize_t (*listxattr) (struct dentry *, char *, size_t); void (*update_time)(struct inode *, struct timespec *, int); int (*atomic_open)(struct inode *, struct dentry *, struct file *, - unsigned open_flag, umode_t create_mode, int *opened); + unsigned open_flag, umode_t create_mode); int (*tmpfile) (struct inode *, struct dentry *, umode_t); }; @@ -496,13 +496,15 @@ otherwise noted. atomic_open: called on the last component of an open. Using this optional method the filesystem can look up, possibly create and open the file in - one atomic operation. If it cannot perform this (e.g. the file type - turned out to be wrong) it may signal this by returning 1 instead of - usual 0 or -ve . This method is only called if the last component is - negative or needs lookup. Cached positive dentries are still handled by - f_op->open(). If the file was created, the FILE_CREATED flag should be - set in "opened". In case of O_EXCL the method must only succeed if the - file didn't exist and hence FILE_CREATED shall always be set on success. + one atomic operation. If it wants to leave actual opening to the + caller (e.g. if the file turned out to be a symlink, device, or just + something filesystem won't do atomic open for), it may signal this by + returning finish_no_open(file, dentry). This method is only called if + the last component is negative or needs lookup. Cached positive dentries + are still handled by f_op->open(). If the file was created, + FMODE_CREATED flag should be set in file->f_mode. In case of O_EXCL + the method must only succeed if the file didn't exist and hence FMODE_CREATED + shall always be set on success. tmpfile: called in the end of O_TMPFILE open(). Optional, equivalent to atomically creating, opening and unlinking a file in given directory. |