NFS: Fix another O_DIRECT race
Ensure we call unmap_mapping_range() and sync dirty pages to disk before
doing an NFS direct write.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
diff --git a/fs/nfs/direct.c b/fs/nfs/direct.c
index b497c71..07922881 100644
--- a/fs/nfs/direct.c
+++ b/fs/nfs/direct.c
@@ -678,15 +678,9 @@
if (!count)
goto out;
- if (mapping->nrpages) {
- retval = filemap_fdatawrite(mapping);
- if (retval == 0)
- retval = nfs_wb_all(inode);
- if (retval == 0)
- retval = filemap_fdatawait(mapping);
- if (retval)
- goto out;
- }
+ retval = nfs_sync_mapping(mapping);
+ if (retval)
+ goto out;
retval = nfs_direct_read(inode, ctx, &iov, pos, 1);
if (retval > 0)
@@ -764,15 +758,9 @@
if (!count)
goto out;
- if (mapping->nrpages) {
- retval = filemap_fdatawrite(mapping);
- if (retval == 0)
- retval = nfs_wb_all(inode);
- if (retval == 0)
- retval = filemap_fdatawait(mapping);
- if (retval)
- goto out;
- }
+ retval = nfs_sync_mapping(mapping);
+ if (retval)
+ goto out;
retval = nfs_direct_write(inode, ctx, &iov, pos, 1);
if (mapping->nrpages)
diff --git a/fs/nfs/file.c b/fs/nfs/file.c
index 57d3e77..eb5cd4c 100644
--- a/fs/nfs/file.c
+++ b/fs/nfs/file.c
@@ -433,11 +433,7 @@
* Flush all pending writes before doing anything
* with locks..
*/
- filemap_fdatawrite(filp->f_mapping);
- down(&inode->i_sem);
- nfs_wb_all(inode);
- up(&inode->i_sem);
- filemap_fdatawait(filp->f_mapping);
+ nfs_sync_mapping(filp->f_mapping);
/* NOTE: special case
* If we're signalled while cleaning up locks on process exit, we
@@ -465,15 +461,8 @@
* Flush all pending writes before doing anything
* with locks..
*/
- status = filemap_fdatawrite(filp->f_mapping);
- if (status == 0) {
- down(&inode->i_sem);
- status = nfs_wb_all(inode);
- up(&inode->i_sem);
- if (status == 0)
- status = filemap_fdatawait(filp->f_mapping);
- }
- if (status < 0)
+ status = nfs_sync_mapping(filp->f_mapping);
+ if (status != 0)
goto out;
lock_kernel();
@@ -497,11 +486,7 @@
* Make sure we clear the cache whenever we try to get the lock.
* This makes locking act as a cache coherency point.
*/
- filemap_fdatawrite(filp->f_mapping);
- down(&inode->i_sem);
- nfs_wb_all(inode); /* we may have slept */
- up(&inode->i_sem);
- filemap_fdatawait(filp->f_mapping);
+ nfs_sync_mapping(filp->f_mapping);
nfs_zap_caches(inode);
out:
rpc_clnt_sigunmask(NFS_CLIENT(inode), &oldset);
diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c
index afd75d0..432f41c 100644
--- a/fs/nfs/inode.c
+++ b/fs/nfs/inode.c
@@ -640,6 +640,27 @@
return 0;
}
+/**
+ * nfs_sync_mapping - helper to flush all mmapped dirty data to disk
+ */
+int nfs_sync_mapping(struct address_space *mapping)
+{
+ int ret;
+
+ if (mapping->nrpages == 0)
+ return 0;
+ unmap_mapping_range(mapping, 0, 0, 0);
+ ret = filemap_fdatawrite(mapping);
+ if (ret != 0)
+ goto out;
+ ret = filemap_fdatawait(mapping);
+ if (ret != 0)
+ goto out;
+ ret = nfs_wb_all(mapping->host);
+out:
+ return ret;
+}
+
/*
* Invalidate the local caches
*/
@@ -1179,11 +1200,8 @@
struct nfs_inode *nfsi = NFS_I(inode);
if (nfsi->cache_validity & NFS_INO_INVALID_DATA) {
- if (S_ISREG(inode->i_mode)) {
- if (filemap_fdatawrite(mapping) == 0)
- filemap_fdatawait(mapping);
- nfs_wb_all(inode);
- }
+ if (S_ISREG(inode->i_mode))
+ nfs_sync_mapping(mapping);
invalidate_inode_pages2(mapping);
spin_lock(&inode->i_lock);
diff --git a/include/linux/nfs_fs.h b/include/linux/nfs_fs.h
index 12787a9..2516ade 100644
--- a/include/linux/nfs_fs.h
+++ b/include/linux/nfs_fs.h
@@ -291,6 +291,7 @@
/*
* linux/fs/nfs/inode.c
*/
+extern int nfs_sync_mapping(struct address_space *mapping);
extern void nfs_zap_caches(struct inode *);
extern struct inode *nfs_fhget(struct super_block *, struct nfs_fh *,
struct nfs_fattr *);