From e261f51f25b98c213e0b3d7f2109b117d714f69d Mon Sep 17 00:00:00 2001 From: Trond Myklebust Date: Tue, 5 Dec 2006 00:35:41 -0500 Subject: [PATCH] NFS: Make nfs_updatepage() mark the page as dirty. This will ensure that we can call set_page_writeback() from within nfs_writepage(), which is always called with the page lock set. Signed-off-by: Trond Myklebust --- fs/nfs/write.c | 73 ++++++++++++++++++++++++++++++---------- include/linux/nfs_page.h | 1 + 2 files changed, 57 insertions(+), 17 deletions(-) diff --git a/fs/nfs/write.c b/fs/nfs/write.c index 0eca6a5421..130528d09a 100644 --- a/fs/nfs/write.c +++ b/fs/nfs/write.c @@ -77,6 +77,7 @@ static struct nfs_page * nfs_update_request(struct nfs_open_context*, struct page *, unsigned int, unsigned int); +static void nfs_mark_request_dirty(struct nfs_page *req); static int nfs_wait_on_write_congestion(struct address_space *, int); static int nfs_wait_on_requests(struct inode *, unsigned long, unsigned int); static long nfs_flush_mapping(struct address_space *mapping, struct writeback_control *wbc, int how); @@ -244,6 +245,48 @@ static int wb_priority(struct writeback_control *wbc) return 0; } +/* + * Find an associated nfs write request, and prepare to flush it out + * Returns 1 if there was no write request, or if the request was + * already tagged by nfs_set_page_dirty.Returns 0 if the request + * was not tagged. + * May also return an error if the user signalled nfs_wait_on_request(). + */ +static int nfs_page_mark_flush(struct page *page) +{ + struct nfs_page *req; + spinlock_t *req_lock = &NFS_I(page->mapping->host)->req_lock; + int ret; + + spin_lock(req_lock); + for(;;) { + req = nfs_page_find_request_locked(page); + if (req == NULL) { + spin_unlock(req_lock); + return 1; + } + if (nfs_lock_request_dontget(req)) + break; + /* Note: If we hold the page lock, as is the case in nfs_writepage, + * then the call to nfs_lock_request_dontget() will always + * succeed provided that someone hasn't already marked the + * request as dirty (in which case we don't care). + */ + spin_unlock(req_lock); + ret = nfs_wait_on_request(req); + nfs_release_request(req); + if (ret != 0) + return ret; + spin_lock(req_lock); + } + spin_unlock(req_lock); + if (test_and_set_bit(PG_FLUSHING, &req->wb_flags) == 0) + nfs_mark_request_dirty(req); + ret = test_bit(PG_NEED_FLUSH, &req->wb_flags); + nfs_unlock_request(req); + return ret; +} + /* * Write an mmapped page to the server. */ @@ -251,23 +294,16 @@ static int nfs_writepage_locked(struct page *page, struct writeback_control *wbc { struct nfs_open_context *ctx; struct inode *inode = page->mapping->host; - struct nfs_page *req; unsigned offset; - int err = 0; + int err; nfs_inc_stats(inode, NFSIOS_VFSWRITEPAGE); nfs_add_stats(inode, NFSIOS_WRITEPAGES, 1); - req = nfs_page_find_request(page); - if (req != NULL) { - int flushme = test_bit(PG_NEED_FLUSH, &req->wb_flags); - nfs_release_request(req); - if (!flushme) - goto out; - /* Ensure we've flushed out the invalid write */ - nfs_wb_page_priority(inode, page, wb_priority(wbc) | FLUSH_STABLE | FLUSH_NOWRITEPAGE); - } - + err = nfs_page_mark_flush(page); + if (err <= 0) + goto out; + err = 0; offset = nfs_page_length(page); if (!offset) goto out; @@ -279,7 +315,11 @@ static int nfs_writepage_locked(struct page *page, struct writeback_control *wbc } err = nfs_writepage_setup(ctx, page, 0, offset); put_nfs_open_context(ctx); - + if (err != 0) + goto out; + err = nfs_page_mark_flush(page); + if (err > 0) + err = 0; out: if (!wbc->for_writepages) nfs_flush_mapping(page->mapping, wbc, wb_priority(wbc)); @@ -409,8 +449,7 @@ nfs_mark_request_dirty(struct nfs_page *req) static inline int nfs_dirty_request(struct nfs_page *req) { - struct nfs_inode *nfsi = NFS_I(req->wb_context->dentry->d_inode); - return !list_empty(&req->wb_list) && req->wb_list_head == &nfsi->dirty; + return test_bit(PG_FLUSHING, &req->wb_flags) == 0; } #if defined(CONFIG_NFS_V3) || defined(CONFIG_NFS_V4) @@ -628,7 +667,6 @@ static struct nfs_page * nfs_update_request(struct nfs_open_context* ctx, return ERR_PTR(error); } spin_unlock(&nfsi->req_lock); - nfs_mark_request_dirty(new); return new; } spin_unlock(&nfsi->req_lock); @@ -684,7 +722,7 @@ int nfs_flush_incompatible(struct file *file, struct page *page) if (req == NULL) return 0; do_flush = req->wb_page != page || req->wb_context != ctx - || test_bit(PG_NEED_FLUSH, &req->wb_flags); + || !nfs_dirty_request(req); nfs_release_request(req); if (!do_flush) return 0; @@ -723,6 +761,7 @@ int nfs_updatepage(struct file *file, struct page *page, } status = nfs_writepage_setup(ctx, page, offset, count); + __set_page_dirty_nobuffers(page); dprintk("NFS: nfs_updatepage returns %d (isize %Ld)\n", status, (long long)i_size_read(inode)); diff --git a/include/linux/nfs_page.h b/include/linux/nfs_page.h index d111be6391..2e555d49c9 100644 --- a/include/linux/nfs_page.h +++ b/include/linux/nfs_page.h @@ -31,6 +31,7 @@ #define PG_NEED_COMMIT 1 #define PG_NEED_RESCHED 2 #define PG_NEED_FLUSH 3 +#define PG_FLUSHING 4 struct nfs_inode; struct nfs_page { -- 2.39.5