NFS: Fix a race with the new commit code

This patch fixes a race which occurs due to the fact that we release the
PG_writeback flag while still holding the nfs_page locked.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
This commit is contained in:
Trond Myklebust 2010-04-09 19:07:08 -04:00
Родитель b80c3cb628
Коммит a6305ddb08
1 изменённых файлов: 10 добавлений и 7 удалений

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@ -201,6 +201,7 @@ static int nfs_set_page_writeback(struct page *page)
struct inode *inode = page->mapping->host;
struct nfs_server *nfss = NFS_SERVER(inode);
page_cache_get(page);
if (atomic_long_inc_return(&nfss->writeback) >
NFS_CONGESTION_ON_THRESH) {
set_bdi_congested(&nfss->backing_dev_info,
@ -216,6 +217,7 @@ static void nfs_end_page_writeback(struct page *page)
struct nfs_server *nfss = NFS_SERVER(inode);
end_page_writeback(page);
page_cache_release(page);
if (atomic_long_dec_return(&nfss->writeback) < NFS_CONGESTION_OFF_THRESH)
clear_bdi_congested(&nfss->backing_dev_info, BLK_RW_ASYNC);
}
@ -665,6 +667,7 @@ static int nfs_writepage_setup(struct nfs_open_context *ctx, struct page *page,
/* Update file length */
nfs_grow_file(page, offset, count);
nfs_mark_uptodate(page, req->wb_pgbase, req->wb_bytes);
nfs_mark_request_dirty(req);
nfs_clear_page_tag_locked(req);
return 0;
}
@ -749,13 +752,12 @@ int nfs_updatepage(struct file *file, struct page *page,
static void nfs_writepage_release(struct nfs_page *req)
{
struct page *page = req->wb_page;
if (PageError(req->wb_page) || !nfs_reschedule_unstable_write(req)) {
nfs_end_page_writeback(req->wb_page);
if (PageError(req->wb_page) || !nfs_reschedule_unstable_write(req))
nfs_inode_remove_request(req);
} else
nfs_end_page_writeback(req->wb_page);
nfs_clear_page_tag_locked(req);
nfs_end_page_writeback(page);
}
static int flush_task_priority(int how)
@ -847,9 +849,11 @@ static int nfs_write_rpcsetup(struct nfs_page *req,
*/
static void nfs_redirty_request(struct nfs_page *req)
{
struct page *page = req->wb_page;
nfs_mark_request_dirty(req);
nfs_end_page_writeback(req->wb_page);
nfs_clear_page_tag_locked(req);
nfs_end_page_writeback(page);
}
/*
@ -1084,16 +1088,15 @@ static void nfs_writeback_release_full(void *calldata)
if (nfs_write_need_commit(data)) {
memcpy(&req->wb_verf, &data->verf, sizeof(req->wb_verf));
nfs_mark_request_commit(req);
nfs_end_page_writeback(page);
dprintk(" marked for commit\n");
goto next;
}
dprintk(" OK\n");
remove_request:
nfs_end_page_writeback(page);
nfs_inode_remove_request(req);
next:
nfs_clear_page_tag_locked(req);
nfs_end_page_writeback(page);
}
nfs_writedata_release(calldata);
}