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Diffstat (limited to 'fs/hostfs/hostfs_kern.c')
-rw-r--r--fs/hostfs/hostfs_kern.c43
1 files changed, 31 insertions, 12 deletions
diff --git a/fs/hostfs/hostfs_kern.c b/fs/hostfs/hostfs_kern.c
index 8130ce93a06..dd1e55535a4 100644
--- a/fs/hostfs/hostfs_kern.c
+++ b/fs/hostfs/hostfs_kern.c
@@ -302,27 +302,22 @@ int hostfs_readdir(struct file *file, void *ent, filldir_t filldir)
int hostfs_file_open(struct inode *ino, struct file *file)
{
+ static DEFINE_MUTEX(open_mutex);
char *name;
fmode_t mode = 0;
+ int err;
int r = 0, w = 0, fd;
mode = file->f_mode & (FMODE_READ | FMODE_WRITE);
if ((mode & HOSTFS_I(ino)->mode) == mode)
return 0;
- /*
- * The file may already have been opened, but with the wrong access,
- * so this resets things and reopens the file with the new access.
- */
- if (HOSTFS_I(ino)->fd != -1) {
- close_file(&HOSTFS_I(ino)->fd);
- HOSTFS_I(ino)->fd = -1;
- }
+ mode |= HOSTFS_I(ino)->mode;
- HOSTFS_I(ino)->mode |= mode;
- if (HOSTFS_I(ino)->mode & FMODE_READ)
+retry:
+ if (mode & FMODE_READ)
r = 1;
- if (HOSTFS_I(ino)->mode & FMODE_WRITE)
+ if (mode & FMODE_WRITE)
w = 1;
if (w)
r = 1;
@@ -335,7 +330,31 @@ int hostfs_file_open(struct inode *ino, struct file *file)
__putname(name);
if (fd < 0)
return fd;
- FILE_HOSTFS_I(file)->fd = fd;
+
+ mutex_lock(&open_mutex);
+ /* somebody else had handled it first? */
+ if ((mode & HOSTFS_I(ino)->mode) == mode) {
+ mutex_unlock(&open_mutex);
+ return 0;
+ }
+ if ((mode | HOSTFS_I(ino)->mode) != mode) {
+ mode |= HOSTFS_I(ino)->mode;
+ mutex_unlock(&open_mutex);
+ close_file(&fd);
+ goto retry;
+ }
+ if (HOSTFS_I(ino)->fd == -1) {
+ HOSTFS_I(ino)->fd = fd;
+ } else {
+ err = replace_file(fd, HOSTFS_I(ino)->fd);
+ close_file(&fd);
+ if (err < 0) {
+ mutex_unlock(&open_mutex);
+ return err;
+ }
+ }
+ HOSTFS_I(ino)->mode = mode;
+ mutex_unlock(&open_mutex);
return 0;
}