Using the BKL in llseek() does not protect the inode's i_size from
modification since the i_size is protected by a seqlock nowadays. Since
default_llseek() is already using the i_size_read() wrapper it is not the
BKL which is serializing the access here.
The access to file->f_pos is not protected by the BKL either since its
access in vfs_write()/vfs_read() is not protected by any lock. If the BKL
is not protecting anything here it can clearly get removed.
Signed-off-by: Jan Blunck <jblunck@xxxxxxx>
Cc: Arnd Bergmann <arnd@xxxxxxxx>
Cc: Christoph Hellwig <hch@xxxxxxxxxxxxx>
Cc: Frédéric Weisbecker <fweisbec@xxxxxxxxx>
Cc: John Kacur <jkacur@xxxxxxxxxx>
---
fs/read_write.c | 2 --
1 files changed, 0 insertions(+), 2 deletions(-)
diff --git a/fs/read_write.c b/fs/read_write.c
index 7a01d11..cbe54e4 100644
--- a/fs/read_write.c
+++ b/fs/read_write.c
@@ -113,7 +113,6 @@ loff_t default_llseek(struct file *file, loff_t offset, int origin)
{
loff_t retval;
- lock_kernel();
switch (origin) {
case SEEK_END:
offset += i_size_read(file->f_path.dentry->d_inode);
@@ -134,7 +133,6 @@ loff_t default_llseek(struct file *file, loff_t offset, int origin)
retval = offset;
}
out:
- unlock_kernel();
return retval;
}
EXPORT_SYMBOL(default_llseek);
--
1.6.4.2
--
To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
