From afddba49d18f346e5cc2938b6ed7c512db18ca68 Mon Sep 17 00:00:00 2001 From: Nick Piggin Date: Tue, 16 Oct 2007 01:25:01 -0700 Subject: fs: introduce write_begin, write_end, and perform_write aops These are intended to replace prepare_write and commit_write with more flexible alternatives that are also able to avoid the buffered write deadlock problems efficiently (which prepare_write is unable to do). [mark.fasheh@oracle.com: API design contributions, code review and fixes] [akpm@linux-foundation.org: various fixes] [dmonakhov@sw.ru: new aop block_write_begin fix] Signed-off-by: Nick Piggin Signed-off-by: Mark Fasheh Signed-off-by: Dmitriy Monakhov Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/namei.c | 46 +++++++++++----------------------------------- 1 file changed, 11 insertions(+), 35 deletions(-) (limited to 'fs/namei.c') diff --git a/fs/namei.c b/fs/namei.c index a83160acd748..b40b8084eefc 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -2729,53 +2729,29 @@ int __page_symlink(struct inode *inode, const char *symname, int len, { struct address_space *mapping = inode->i_mapping; struct page *page; + void *fsdata; int err; char *kaddr; retry: - err = -ENOMEM; - page = find_or_create_page(mapping, 0, gfp_mask); - if (!page) - goto fail; - err = mapping->a_ops->prepare_write(NULL, page, 0, len-1); - if (err == AOP_TRUNCATED_PAGE) { - page_cache_release(page); - goto retry; - } + err = pagecache_write_begin(NULL, mapping, 0, len-1, + AOP_FLAG_UNINTERRUPTIBLE, &page, &fsdata); if (err) - goto fail_map; + goto fail; + kaddr = kmap_atomic(page, KM_USER0); memcpy(kaddr, symname, len-1); kunmap_atomic(kaddr, KM_USER0); - err = mapping->a_ops->commit_write(NULL, page, 0, len-1); - if (err == AOP_TRUNCATED_PAGE) { - page_cache_release(page); - goto retry; - } - if (err) - goto fail_map; - /* - * Notice that we are _not_ going to block here - end of page is - * unmapped, so this will only try to map the rest of page, see - * that it is unmapped (typically even will not look into inode - - * ->i_size will be enough for everything) and zero it out. - * OTOH it's obviously correct and should make the page up-to-date. - */ - if (!PageUptodate(page)) { - err = mapping->a_ops->readpage(NULL, page); - if (err != AOP_TRUNCATED_PAGE) - wait_on_page_locked(page); - } else { - unlock_page(page); - } - page_cache_release(page); + + err = pagecache_write_end(NULL, mapping, 0, len-1, len-1, + page, fsdata); if (err < 0) goto fail; + if (err < len-1) + goto retry; + mark_inode_dirty(inode); return 0; -fail_map: - unlock_page(page); - page_cache_release(page); fail: return err; } -- cgit v1.2.2