From 750b4987b0cd4d408e54cb83a80a067cbe690feb Mon Sep 17 00:00:00 2001 From: Nick Piggin Date: Wed, 16 Sep 2009 11:50:12 +0200 Subject: HWPOISON: Refactor truncate to allow direct truncating of page v2 Extract out truncate_inode_page() out of the truncate path so that it can be used by memory-failure.c [AK: description, headers, fix typos] v2: Some white space changes from Fengguang Wu Signed-off-by: Andi Kleen --- mm/truncate.c | 29 +++++++++++++++-------------- 1 file changed, 15 insertions(+), 14 deletions(-) (limited to 'mm/truncate.c') diff --git a/mm/truncate.c b/mm/truncate.c index ccc3ecf7cb98..2519a7c92873 100644 --- a/mm/truncate.c +++ b/mm/truncate.c @@ -93,11 +93,11 @@ EXPORT_SYMBOL(cancel_dirty_page); * its lock, b) when a concurrent invalidate_mapping_pages got there first and * c) when tmpfs swizzles a page between a tmpfs inode and swapper_space. */ -static void +static int truncate_complete_page(struct address_space *mapping, struct page *page) { if (page->mapping != mapping) - return; + return -EIO; if (page_has_private(page)) do_invalidatepage(page, 0); @@ -108,6 +108,7 @@ truncate_complete_page(struct address_space *mapping, struct page *page) remove_from_page_cache(page); ClearPageMappedToDisk(page); page_cache_release(page); /* pagecache ref */ + return 0; } /* @@ -135,6 +136,16 @@ invalidate_complete_page(struct address_space *mapping, struct page *page) return ret; } +int truncate_inode_page(struct address_space *mapping, struct page *page) +{ + if (page_mapped(page)) { + unmap_mapping_range(mapping, + (loff_t)page->index << PAGE_CACHE_SHIFT, + PAGE_CACHE_SIZE, 0); + } + return truncate_complete_page(mapping, page); +} + /** * truncate_inode_pages - truncate range of pages specified by start & end byte offsets * @mapping: mapping to truncate @@ -196,12 +207,7 @@ void truncate_inode_pages_range(struct address_space *mapping, unlock_page(page); continue; } - if (page_mapped(page)) { - unmap_mapping_range(mapping, - (loff_t)page_index<index<index > next) next = page->index; next++; - truncate_complete_page(mapping, page); unlock_page(page); } pagevec_release(&pvec); -- cgit v1.2.3 From 83f786680aec8d030184f7ced1a0a3dd8ac81764 Mon Sep 17 00:00:00 2001 From: Wu Fengguang Date: Wed, 16 Sep 2009 11:50:13 +0200 Subject: HWPOISON: Add invalidate_inode_page Add a simple way to invalidate a single page This is just a refactoring of the truncate.c code. Originally from Fengguang, modified by Andi Kleen. Signed-off-by: Andi Kleen --- mm/truncate.c | 26 ++++++++++++++++++++------ 1 file changed, 20 insertions(+), 6 deletions(-) (limited to 'mm/truncate.c') diff --git a/mm/truncate.c b/mm/truncate.c index 2519a7c92873..ea132f7ea2d2 100644 --- a/mm/truncate.c +++ b/mm/truncate.c @@ -146,6 +146,24 @@ int truncate_inode_page(struct address_space *mapping, struct page *page) return truncate_complete_page(mapping, page); } +/* + * Safely invalidate one page from its pagecache mapping. + * It only drops clean, unused pages. The page must be locked. + * + * Returns 1 if the page is successfully invalidated, otherwise 0. + */ +int invalidate_inode_page(struct page *page) +{ + struct address_space *mapping = page_mapping(page); + if (!mapping) + return 0; + if (PageDirty(page) || PageWriteback(page)) + return 0; + if (page_mapped(page)) + return 0; + return invalidate_complete_page(mapping, page); +} + /** * truncate_inode_pages - truncate range of pages specified by start & end byte offsets * @mapping: mapping to truncate @@ -312,12 +330,8 @@ unsigned long invalidate_mapping_pages(struct address_space *mapping, if (lock_failed) continue; - if (PageDirty(page) || PageWriteback(page)) - goto unlock; - if (page_mapped(page)) - goto unlock; - ret += invalidate_complete_page(mapping, page); -unlock: + ret += invalidate_inode_page(page); + unlock_page(page); if (next > end) break; -- cgit v1.2.3 From 257187362123f15d9d1e09918cf87cebbea4e786 Mon Sep 17 00:00:00 2001 From: Andi Kleen Date: Wed, 16 Sep 2009 11:50:13 +0200 Subject: HWPOISON: Define a new error_remove_page address space op for async truncation Truncating metadata pages is not safe right now before we haven't audited all file systems. To enable truncation only for data address space define a new address_space callback error_remove_page. This is used for memory_failure.c memory error handling. This can be then set to truncate_inode_page() This patch just defines the new operation and adds documentation. Callers and users come in followon patches. Signed-off-by: Andi Kleen --- mm/truncate.c | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) (limited to 'mm/truncate.c') diff --git a/mm/truncate.c b/mm/truncate.c index ea132f7ea2d2..a17b3977cfdf 100644 --- a/mm/truncate.c +++ b/mm/truncate.c @@ -146,6 +146,23 @@ int truncate_inode_page(struct address_space *mapping, struct page *page) return truncate_complete_page(mapping, page); } +/* + * Used to get rid of pages on hardware memory corruption. + */ +int generic_error_remove_page(struct address_space *mapping, struct page *page) +{ + if (!mapping) + return -EINVAL; + /* + * Only punch for normal data pages for now. + * Handling other types like directories would need more auditing. + */ + if (!S_ISREG(mapping->host->i_mode)) + return -EIO; + return truncate_inode_page(mapping, page); +} +EXPORT_SYMBOL(generic_error_remove_page); + /* * Safely invalidate one page from its pagecache mapping. * It only drops clean, unused pages. The page must be locked. -- cgit v1.2.3