The count for cifsFileInfo is currently an atomic, but that just adds complexity for little value. We generally need to hold cifs_file_list_lock to traverse the lists anyway so we might as well make this counter non-atomic and simply use the cifs_file_list_lock to protect it.
Signed-off-by: Jeff Layton <[email protected]> --- fs/cifs/cifsglob.h | 9 ++++++--- fs/cifs/file.c | 8 +++++--- 2 files changed, 11 insertions(+), 6 deletions(-) diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h index 531a768..f3c4e00 100644 --- a/fs/cifs/cifsglob.h +++ b/fs/cifs/cifsglob.h @@ -393,16 +393,19 @@ struct cifsFileInfo { struct list_head llist; /* list of byte range locks we have. */ bool invalidHandle:1; /* file closed via session abend */ bool oplock_break_cancelled:1; - atomic_t count; /* reference count */ + int count; /* refcount -- protected by cifs_file_list_lock */ struct mutex fh_mutex; /* prevents reopen race after dead ses*/ struct cifs_search_info srch_inf; struct work_struct oplock_break; /* work for oplock breaks */ }; -/* Take a reference on the file private data */ +/* + * Take a reference on the file private data. Must be called with + * cifs_file_list_lock held for read or write. + */ static inline void cifsFileInfo_get(struct cifsFileInfo *cifs_file) { - atomic_inc(&cifs_file->count); + ++cifs_file->count; } void cifsFileInfo_put(struct cifsFileInfo *cifs_file); diff --git a/fs/cifs/file.c b/fs/cifs/file.c index 157ab9d..3a917be 100644 --- a/fs/cifs/file.c +++ b/fs/cifs/file.c @@ -172,6 +172,7 @@ cifs_new_fileinfo(__u16 fileHandle, struct file *file, if (pCifsFile == NULL) return pCifsFile; + pCifsFile->count = 1; pCifsFile->netfid = fileHandle; pCifsFile->pid = current->tgid; pCifsFile->uid = current_fsuid(); @@ -182,7 +183,6 @@ cifs_new_fileinfo(__u16 fileHandle, struct file *file, mutex_init(&pCifsFile->fh_mutex); mutex_init(&pCifsFile->lock_mutex); INIT_LIST_HEAD(&pCifsFile->llist); - atomic_set(&pCifsFile->count, 1); INIT_WORK(&pCifsFile->oplock_break, cifs_oplock_break); write_lock(&cifs_file_list_lock); @@ -208,7 +208,8 @@ cifs_new_fileinfo(__u16 fileHandle, struct file *file, /* * Release a reference on the file private data. This may involve closing - * the filehandle out on the server. + * the filehandle out on the server. Must be called without holding + * cifs_file_list_lock. */ void cifsFileInfo_put(struct cifsFileInfo *cifs_file) { @@ -217,7 +218,7 @@ void cifsFileInfo_put(struct cifsFileInfo *cifs_file) struct cifsLockInfo *li, *tmp; write_lock(&cifs_file_list_lock); - if (!atomic_dec_and_test(&cifs_file_list_lock)) { + if (--cifs_file->count > 0) { write_unlock(&cifs_file_list_lock); return; } @@ -2259,6 +2260,7 @@ void cifs_oplock_break(struct work_struct *work) cifs_oplock_break_put(cfile); } +/* must be called while holding cifs_file_list_lock for read or write */ void cifs_oplock_break_get(struct cifsFileInfo *cfile) { cifs_sb_active(cfile->dentry->d_sb); -- 1.7.2.3 -- To unsubscribe from this list: send the line "unsubscribe linux-cifs" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
