On Wed, 25 Jul 2012 14:48:34 -0400 Jeff Layton <[email protected]> wrote:
> The readpages bug is a regression that was introduced in 6993f74a5. > This also fixes a couple of similar bugs in the uncached read and write > codepaths. > > Also, prevent this sort of thing in the future by having cifsFileInfo_get > take the spinlock itself, and adding a _locked variant for use in places > that are already holding the lock. The _put code has always done that > so this makes for a less confusing interface. > > Signed-off-by: Jeff Layton <[email protected]> Oh, this definitely needs to go to stable too. Steve, can you add this? Cc: <[email protected]> # 3.5+ > --- > fs/cifs/cifsglob.h | 6 +++--- > fs/cifs/file.c | 17 ++++++++++++----- > 2 files changed, 15 insertions(+), 8 deletions(-) > > diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h > index bcdf4d4..497da5c 100644 > --- a/fs/cifs/cifsglob.h > +++ b/fs/cifs/cifsglob.h > @@ -765,13 +765,13 @@ struct cifs_io_parms { > * Take a reference on the file private data. Must be called with > * cifs_file_list_lock held. > */ > -static inline > -struct cifsFileInfo *cifsFileInfo_get(struct cifsFileInfo *cifs_file) > +static inline void > +cifsFileInfo_get_locked(struct cifsFileInfo *cifs_file) > { > ++cifs_file->count; > - return cifs_file; > } > > +struct cifsFileInfo *cifsFileInfo_get(struct cifsFileInfo *cifs_file); > void cifsFileInfo_put(struct cifsFileInfo *cifs_file); > > /* > diff --git a/fs/cifs/file.c b/fs/cifs/file.c > index 07e9d41..9154192 100644 > --- a/fs/cifs/file.c > +++ b/fs/cifs/file.c > @@ -284,6 +284,15 @@ cifs_new_fileinfo(__u16 fileHandle, struct file *file, > > static void cifs_del_lock_waiters(struct cifsLockInfo *lock); > > +struct cifsFileInfo * > +cifsFileInfo_get(struct cifsFileInfo *cifs_file) > +{ > + spin_lock(&cifs_file_list_lock); > + cifsFileInfo_get_locked(cifs_file); > + spin_unlock(&cifs_file_list_lock); > + return cifs_file; > +} > + > /* > * Release a reference on the file private data. This may involve closing > * the filehandle out on the server. Must be called without holding > @@ -1562,7 +1571,7 @@ struct cifsFileInfo *find_readable_file(struct > cifsInodeInfo *cifs_inode, > if (!open_file->invalidHandle) { > /* found a good file */ > /* lock it so it will not be closed on us */ > - cifsFileInfo_get(open_file); > + cifsFileInfo_get_locked(open_file); > spin_unlock(&cifs_file_list_lock); > return open_file; > } /* else might as well continue, and look for > @@ -1614,7 +1623,7 @@ refind_writable: > if (OPEN_FMODE(open_file->f_flags) & FMODE_WRITE) { > if (!open_file->invalidHandle) { > /* found a good writable file */ > - cifsFileInfo_get(open_file); > + cifsFileInfo_get_locked(open_file); > spin_unlock(&cifs_file_list_lock); > return open_file; > } else { > @@ -1631,7 +1640,7 @@ refind_writable: > > if (inv_file) { > any_available = false; > - cifsFileInfo_get(inv_file); > + cifsFileInfo_get_locked(inv_file); > } > > spin_unlock(&cifs_file_list_lock); > @@ -3082,8 +3091,6 @@ static int cifs_readpages(struct file *file, struct > address_space *mapping, > break; > } > > - spin_lock(&cifs_file_list_lock); > - spin_unlock(&cifs_file_list_lock); > rdata->cfile = cifsFileInfo_get(open_file); > rdata->mapping = mapping; > rdata->offset = offset; -- Jeff Layton <[email protected]> -- 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
