[PATCH] ufs: ufs_get_locked_page() race fix (1fb32b7b) · Commits · 戴 / test

As discussed earlier: http://lkml.org/lkml/2006/6/28/136 this patch fixes such issue: `ufs_get_locked_page' takes page from cache after that `vmtruncate' takes page and deletes it from cache `ufs_get_locked_page' locks page, and reports about EIO error. Also because of find_lock_page always return valid page or NULL, we have no need to check it if page not NULL. Signed-off-by:

Evgeniy Dushistov <dushistov@mail.ru> Signed-off-by:

Andrew Morton <akpm@osdl.org> Signed-off-by:

Linus Torvalds <torvalds@osdl.org>

fs/ufs/util.c

+8 −7

Original line number	Diff line number	Diff line
		@@ -257,6 +257,7 @@ try_again:
		page = read_cache_page(mapping, index,
		(filler_t*)mapping->a_ops->readpage,
		NULL);

		if (IS_ERR(page)) {
		printk(KERN_ERR "ufs_change_blocknr: "
		"read_cache_page error: ino %lu, index: %lu\n",
		@@ -266,6 +267,13 @@ try_again:

		lock_page(page);

		if (unlikely(page->mapping == NULL)) {
		/* Truncate got there first */
		unlock_page(page);
		page_cache_release(page);
		goto try_again;
		}

		if (!PageUptodate(page) \|\| PageError(page)) {
		unlock_page(page);
		page_cache_release(page);
		@@ -275,14 +283,7 @@ try_again:
		mapping->host->i_ino, index);

		page = ERR_PTR(-EIO);
		goto out;
		}
		}

		if (unlikely(!page->mapping \|\| !page_has_buffers(page))) {
		unlock_page(page);
		page_cache_release(page);
		goto try_again;/we really need these buffers/
		}
		out:
		return page;

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