From b608b283a962caaa280756bc8563016a71712acf Mon Sep 17 00:00:00 2001 From: Trond Myklebust Date: Fri, 30 Jul 2010 15:31:54 -0400 Subject: NFS: kswapd must not block in nfs_release_page See https://bugzilla.kernel.org/show_bug.cgi?id=16056 If other processes are blocked waiting for kswapd to free up some memory so that they can make progress, then we cannot allow kswapd to block on those processes. Signed-off-by: Trond Myklebust Cc: stable@kernel.org --- fs/nfs/write.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'fs/nfs/write.c') diff --git a/fs/nfs/write.c b/fs/nfs/write.c index 91679e2631e..0a6c65a1f9d 100644 --- a/fs/nfs/write.c +++ b/fs/nfs/write.c @@ -1379,7 +1379,7 @@ static const struct rpc_call_ops nfs_commit_ops = { .rpc_release = nfs_commit_release, }; -static int nfs_commit_inode(struct inode *inode, int how) +int nfs_commit_inode(struct inode *inode, int how) { LIST_HEAD(head); int may_wait = how & FLUSH_SYNC; @@ -1443,7 +1443,7 @@ out_mark_dirty: return ret; } #else -static int nfs_commit_inode(struct inode *inode, int how) +int nfs_commit_inode(struct inode *inode, int how) { return 0; } -- cgit v1.2.3-70-g09d2 From cfb506e1d330387dfaf334dd493b3773d388863d Mon Sep 17 00:00:00 2001 From: Trond Myklebust Date: Fri, 30 Jul 2010 15:31:57 -0400 Subject: NFS: Ensure that writepage respects the nonblock flag Signed-off-by: Trond Myklebust --- fs/nfs/write.c | 23 +++++++++++++++++------ 1 file changed, 17 insertions(+), 6 deletions(-) (limited to 'fs/nfs/write.c') diff --git a/fs/nfs/write.c b/fs/nfs/write.c index 0a6c65a1f9d..bb72ad34d51 100644 --- a/fs/nfs/write.c +++ b/fs/nfs/write.c @@ -222,7 +222,7 @@ static void nfs_end_page_writeback(struct page *page) clear_bdi_congested(&nfss->backing_dev_info, BLK_RW_ASYNC); } -static struct nfs_page *nfs_find_and_lock_request(struct page *page) +static struct nfs_page *nfs_find_and_lock_request(struct page *page, bool nonblock) { struct inode *inode = page->mapping->host; struct nfs_page *req; @@ -241,7 +241,10 @@ static struct nfs_page *nfs_find_and_lock_request(struct page *page) * request as dirty (in which case we don't care). */ spin_unlock(&inode->i_lock); - ret = nfs_wait_on_request(req); + if (!nonblock) + ret = nfs_wait_on_request(req); + else + ret = -EAGAIN; nfs_release_request(req); if (ret != 0) return ERR_PTR(ret); @@ -256,12 +259,12 @@ static struct nfs_page *nfs_find_and_lock_request(struct page *page) * May return an error if the user signalled nfs_wait_on_request(). */ static int nfs_page_async_flush(struct nfs_pageio_descriptor *pgio, - struct page *page) + struct page *page, bool nonblock) { struct nfs_page *req; int ret = 0; - req = nfs_find_and_lock_request(page); + req = nfs_find_and_lock_request(page, nonblock); if (!req) goto out; ret = PTR_ERR(req); @@ -283,12 +286,20 @@ out: static int nfs_do_writepage(struct page *page, struct writeback_control *wbc, struct nfs_pageio_descriptor *pgio) { struct inode *inode = page->mapping->host; + int ret; nfs_inc_stats(inode, NFSIOS_VFSWRITEPAGE); nfs_add_stats(inode, NFSIOS_WRITEPAGES, 1); nfs_pageio_cond_complete(pgio, page->index); - return nfs_page_async_flush(pgio, page); + ret = nfs_page_async_flush(pgio, page, + wbc->sync_mode == WB_SYNC_NONE || + wbc->nonblocking != 0); + if (ret == -EAGAIN) { + redirty_page_for_writepage(wbc, page); + ret = 0; + } + return ret; } /* @@ -1546,7 +1557,7 @@ int nfs_migrate_page(struct address_space *mapping, struct page *newpage, nfs_fscache_release_page(page, GFP_KERNEL); - req = nfs_find_and_lock_request(page); + req = nfs_find_and_lock_request(page, false); ret = PTR_ERR(req); if (IS_ERR(req)) goto out; -- cgit v1.2.3-70-g09d2 From 77a63f3d1e0a3e7ede8d10f569e8481b13ff47c5 Mon Sep 17 00:00:00 2001 From: Trond Myklebust Date: Sun, 1 Aug 2010 13:40:40 -0400 Subject: NFS: Fix a typo in include/linux/nfs_fs.h nfs_commit_inode() needs to be defined irrespectively of whether or not we are supporting NFSv3 and NFSv4. Allow the compiler to optimise away code in the NFSv2-only case by converting it into an inlined stub function. Reported-and-tested-by: Ingo Molnar Signed-off-by: Trond Myklebust Signed-off-by: Linus Torvalds --- fs/nfs/write.c | 5 ----- include/linux/nfs_fs.h | 6 ++++++ 2 files changed, 6 insertions(+), 5 deletions(-) (limited to 'fs/nfs/write.c') diff --git a/fs/nfs/write.c b/fs/nfs/write.c index bb72ad34d51..9f81bdd91c5 100644 --- a/fs/nfs/write.c +++ b/fs/nfs/write.c @@ -1454,11 +1454,6 @@ out_mark_dirty: return ret; } #else -int nfs_commit_inode(struct inode *inode, int how) -{ - return 0; -} - static int nfs_commit_unstable_pages(struct inode *inode, struct writeback_control *wbc) { return 0; diff --git a/include/linux/nfs_fs.h b/include/linux/nfs_fs.h index f6e2455f13d..bad4d121b16 100644 --- a/include/linux/nfs_fs.h +++ b/include/linux/nfs_fs.h @@ -496,6 +496,12 @@ extern int nfs_wb_page_cancel(struct inode *inode, struct page* page); extern int nfs_commit_inode(struct inode *, int); extern struct nfs_write_data *nfs_commitdata_alloc(void); extern void nfs_commit_free(struct nfs_write_data *wdata); +#else +static inline int +nfs_commit_inode(struct inode *inode, int how) +{ + return 0; +} #endif static inline int -- cgit v1.2.3-70-g09d2