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 <jlayton@xxxxxxxxxx>
---
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;
--
1.7.11.2
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