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| author |   Al Viro <viro@zeniv.linux.org.uk> | 2016-04-20 23:08:32 -0400 |
|---|---|---|
| committer | Al Viro <viro@zeniv.linux.org.uk> | 2016-05-02 19:49:29 -0400 |
| commit | 6192269444ebfbfb42e23c7a6a93c76ffe4b5e51 (patch) | |
| tree | ec40fbbad46725d88f2c16b11ff5976d87f497bb /fs | |
| parent | give readdir(2)/getdents(2)/etc. uniform exclusion with lseek() (diff) | |
| download | linux-dev-6192269444ebfbfb42e23c7a6a93c76ffe4b5e51.tar.xz linux-dev-6192269444ebfbfb42e23c7a6a93c76ffe4b5e51.zip | |
introduce a parallel variant of ->iterate()
New method: ->iterate_shared(). Same arguments as in ->iterate(),
called with the directory locked only shared. Once all filesystems
switch, the old one will be gone.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/coda/dir.c | 18 | ||||
| -rw-r--r-- | fs/exportfs/expfs.c | 2 | ||||
| -rw-r--r-- | fs/readdir.c | 20 |
3 files changed, 29 insertions, 11 deletions
diff --git a/fs/coda/dir.c b/fs/coda/dir.c index 42e731b8c80a..6fb8672c0892 100644 --- a/fs/coda/dir.c +++ b/fs/coda/dir.c @@ -424,16 +424,22 @@ static int coda_readdir(struct file *coda_file, struct dir_context *ctx) BUG_ON(!cfi || cfi->cfi_magic != CODA_MAGIC); host_file = cfi->cfi_container; - if (host_file->f_op->iterate) { + if (host_file->f_op->iterate || host_file->f_op->iterate_shared) { struct inode *host_inode = file_inode(host_file); - - inode_lock(host_inode); ret = -ENOENT; if (!IS_DEADDIR(host_inode)) { - ret = host_file->f_op->iterate(host_file, ctx); - file_accessed(host_file); + if (host_file->f_op->iterate_shared) { + inode_lock_shared(host_inode); + ret = host_file->f_op->iterate_shared(host_file, ctx); + file_accessed(host_file); + inode_unlock_shared(host_inode); + } else { + inode_lock(host_inode); + ret = host_file->f_op->iterate(host_file, ctx); + file_accessed(host_file); + inode_unlock(host_inode); + } } - inode_unlock(host_inode); return ret; } /* Venus: we must read Venus dirents from a file */ diff --git a/fs/exportfs/expfs.c b/fs/exportfs/expfs.c index 402c5caab5ca..207ba8d627ca 100644 --- a/fs/exportfs/expfs.c +++ b/fs/exportfs/expfs.c @@ -312,7 +312,7 @@ static int get_name(const struct path *path, char *name, struct dentry *child) goto out; error = -EINVAL; - if (!file->f_op->iterate) + if (!file->f_op->iterate && !file->f_op->iterate_shared) goto out_close; buffer.sequence = 0; diff --git a/fs/readdir.c b/fs/readdir.c index d7308b8f6cf7..a86c6c04b9bc 100644 --- a/fs/readdir.c +++ b/fs/readdir.c @@ -24,15 +24,21 @@ int iterate_dir(struct file *file, struct dir_context *ctx) { struct inode *inode = file_inode(file); + bool shared = false; int res = -ENOTDIR; - if (!file->f_op->iterate) + if (file->f_op->iterate_shared) + shared = true; + else if (!file->f_op->iterate) goto out; res = security_file_permission(file, MAY_READ); if (res) goto out; - inode_lock(inode); + if (shared) + inode_lock_shared(inode); + else + inode_lock(inode); // res = mutex_lock_killable(&inode->i_mutex); // if (res) // goto out; @@ -40,12 +46,18 @@ int iterate_dir(struct file *file, struct dir_context *ctx) res = -ENOENT; if (!IS_DEADDIR(inode)) { ctx->pos = file->f_pos; - res = file->f_op->iterate(file, ctx); + if (shared) + res = file->f_op->iterate_shared(file, ctx); + else + res = file->f_op->iterate(file, ctx); file->f_pos = ctx->pos; fsnotify_access(file); file_accessed(file); } - inode_unlock(inode); + if (shared) + inode_unlock_shared(inode); + else + inode_unlock(inode); out: return res; } |