aboutsummaryrefslogtreecommitdiff
path: root/fs/coda/file.c
diff options
context:
space:
mode:
authorJan Harkes <jaharkes@cs.cmu.edu>2007-07-21 04:37:26 -0700
committerLinus Torvalds <torvalds@woody.linux-foundation.org>2007-07-21 17:49:14 -0700
commitd3fec424b23c47686efcf3f2004c3f1c1cee4d9c (patch)
treeffad3cf369d35e85fca9a340347eea09caa53ff3 /fs/coda/file.c
parentb50731732f926d6c49fd0724616a7344c31cd5cf (diff)
downloadlinux-linaro-d3fec424b23c47686efcf3f2004c3f1c1cee4d9c.tar.gz
coda: remove CODA_STORE/CODA_RELEASE upcalls
This is an variation on the patch sent by Christoph Hellwig which kills file_count abuse by the Coda kernel module by moving the coda_flush functionality into coda_release. However part of reason we were using the coda_flush callback was to allow Coda to pass errors that occur during writeback from the userspace cache manager back to close(). As Al Viro explained on linux-fsdevel, it is impossible to guarantee that such errors can in fact be returned back to the caller. There are many cases where the last reference to a file is not released by the close system call and it is also impossible to pick some close as a 'last-close' and delay it until all other references have been destroyed. The CODA_STORE/CODA_RELEASE upcall combination is clearly a broken design, and it is better to remove it completely. Signed-off-by: Jan Harkes <jaharkes@cs.cmu.edu> Cc: Christoph Hellwig <hch@lst.de> Cc: Al Viro <viro@ftp.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'fs/coda/file.c')
-rw-r--r--fs/coda/file.c65
1 files changed, 6 insertions, 59 deletions
diff --git a/fs/coda/file.c b/fs/coda/file.c
index 7594962604c..29137ff3ca6 100644
--- a/fs/coda/file.c
+++ b/fs/coda/file.c
@@ -25,10 +25,6 @@
#include "coda_int.h"
-/* if CODA_STORE fails with EOPNOTSUPP, venus clearly doesn't support
- * CODA_STORE/CODA_RELEASE and we fall back on using the CODA_CLOSE upcall */
-static int use_coda_close;
-
static ssize_t
coda_file_read(struct file *coda_file, char __user *buf, size_t count, loff_t *ppos)
{
@@ -163,47 +159,6 @@ int coda_open(struct inode *coda_inode, struct file *coda_file)
return 0;
}
-int coda_flush(struct file *coda_file, fl_owner_t id)
-{
- unsigned short flags = coda_file->f_flags & ~O_EXCL;
- unsigned short coda_flags = coda_flags_to_cflags(flags);
- struct coda_file_info *cfi;
- struct inode *coda_inode;
- int err = 0, fcnt;
-
- lock_kernel();
-
- /* last close semantics */
- fcnt = file_count(coda_file);
- if (fcnt > 1)
- goto out;
-
- /* No need to make an upcall when we have not made any modifications
- * to the file */
- if ((coda_file->f_flags & O_ACCMODE) == O_RDONLY)
- goto out;
-
- if (use_coda_close)
- goto out;
-
- cfi = CODA_FTOC(coda_file);
- BUG_ON(!cfi || cfi->cfi_magic != CODA_MAGIC);
-
- coda_inode = coda_file->f_path.dentry->d_inode;
-
- err = venus_store(coda_inode->i_sb, coda_i2f(coda_inode), coda_flags,
- coda_file->f_uid);
-
- if (err == -EOPNOTSUPP) {
- use_coda_close = 1;
- err = 0;
- }
-
-out:
- unlock_kernel();
- return err;
-}
-
int coda_release(struct inode *coda_inode, struct file *coda_file)
{
unsigned short flags = (coda_file->f_flags) & (~O_EXCL);
@@ -215,21 +170,11 @@ int coda_release(struct inode *coda_inode, struct file *coda_file)
lock_kernel();
- if (!use_coda_close) {
- err = venus_release(coda_inode->i_sb, coda_i2f(coda_inode),
- coda_flags);
- if (err == -EOPNOTSUPP) {
- use_coda_close = 1;
- err = 0;
- }
- }
-
cfi = CODA_FTOC(coda_file);
BUG_ON(!cfi || cfi->cfi_magic != CODA_MAGIC);
- if (use_coda_close)
- err = venus_close(coda_inode->i_sb, coda_i2f(coda_inode),
- coda_flags, coda_file->f_uid);
+ err = venus_close(coda_inode->i_sb, coda_i2f(coda_inode),
+ coda_flags, coda_file->f_uid);
host_inode = cfi->cfi_container->f_path.dentry->d_inode;
cii = ITOC(coda_inode);
@@ -246,7 +191,10 @@ int coda_release(struct inode *coda_inode, struct file *coda_file)
coda_file->private_data = NULL;
unlock_kernel();
- return err;
+
+ /* VFS fput ignores the return value from file_operations->release, so
+ * there is no use returning an error here */
+ return 0;
}
int coda_fsync(struct file *coda_file, struct dentry *coda_dentry, int datasync)
@@ -288,7 +236,6 @@ const struct file_operations coda_file_operations = {
.write = coda_file_write,
.mmap = coda_file_mmap,
.open = coda_open,
- .flush = coda_flush,
.release = coda_release,
.fsync = coda_fsync,
.splice_read = coda_file_splice_read,