diff options
| -rw-r--r-- | fs/ext4/ext4.h | 2 | ||||
| -rw-r--r-- | fs/ext4/extents.c | 19 | ||||
| -rw-r--r-- | fs/ext4/inode.c | 63 |
3 files changed, 70 insertions, 14 deletions
diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h index 4e7de7eaa374..902b7c00c240 100644 --- a/fs/ext4/ext4.h +++ b/fs/ext4/ext4.h @@ -3001,6 +3001,8 @@ extern int ext4_inode_attach_jinode(struct inode *inode); extern int ext4_can_truncate(struct inode *inode); extern int ext4_truncate(struct inode *); extern int ext4_break_layouts(struct inode *); +extern int ext4_truncate_page_cache_block_range(struct inode *inode, + loff_t start, loff_t end); extern int ext4_punch_hole(struct file *file, loff_t offset, loff_t length); extern void ext4_set_inode_flags(struct inode *, bool init); extern int ext4_alloc_da_blocks(struct inode *inode); diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c index a07a98a4b97a..8dc6b4271b15 100644 --- a/fs/ext4/extents.c +++ b/fs/ext4/extents.c @@ -4667,22 +4667,13 @@ static long ext4_zero_range(struct file *file, loff_t offset, goto out_mutex; } - /* - * For journalled data we need to write (and checkpoint) pages - * before discarding page cache to avoid inconsitent data on - * disk in case of crash before zeroing trans is committed. - */ - if (ext4_should_journal_data(inode)) { - ret = filemap_write_and_wait_range(mapping, start, - end - 1); - if (ret) { - filemap_invalidate_unlock(mapping); - goto out_mutex; - } + /* Now release the pages and zero block aligned part of pages */ + ret = ext4_truncate_page_cache_block_range(inode, start, end); + if (ret) { + filemap_invalidate_unlock(mapping); + goto out_mutex; } - /* Now release the pages and zero block aligned part of pages */ - truncate_pagecache_range(inode, start, end - 1); inode_set_mtime_to_ts(inode, inode_set_ctime_current(inode)); ret = ext4_alloc_file_blocks(file, lblk, max_blocks, new_size, diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index 7c54ae5fcbd4..a569b66103a3 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -31,6 +31,7 @@ #include <linux/writeback.h> #include <linux/pagevec.h> #include <linux/mpage.h> +#include <linux/rmap.h> #include <linux/namei.h> #include <linux/uio.h> #include <linux/bio.h> @@ -3902,6 +3903,68 @@ int ext4_update_disksize_before_punch(struct inode *inode, loff_t offset, return ret; } +static inline void ext4_truncate_folio(struct inode *inode, + loff_t start, loff_t end) +{ + unsigned long blocksize = i_blocksize(inode); + struct folio *folio; + + /* Nothing to be done if no complete block needs to be truncated. */ + if (round_up(start, blocksize) >= round_down(end, blocksize)) + return; + + folio = filemap_lock_folio(inode->i_mapping, start >> PAGE_SHIFT); + if (IS_ERR(folio)) + return; + + if (folio_mkclean(folio)) + folio_mark_dirty(folio); + folio_unlock(folio); + folio_put(folio); +} + +int ext4_truncate_page_cache_block_range(struct inode *inode, + loff_t start, loff_t end) +{ + unsigned long blocksize = i_blocksize(inode); + int ret; + + /* + * For journalled data we need to write (and checkpoint) pages + * before discarding page cache to avoid inconsitent data on disk + * in case of crash before freeing or unwritten converting trans + * is committed. + */ + if (ext4_should_journal_data(inode)) { + ret = filemap_write_and_wait_range(inode->i_mapping, start, + end - 1); + if (ret) + return ret; + goto truncate_pagecache; + } + + /* + * If the block size is less than the page size, the file's mapped + * blocks within one page could be freed or converted to unwritten. + * So it's necessary to remove writable userspace mappings, and then + * ext4_page_mkwrite() can be called during subsequent write access + * to these partial folios. + */ + if (!IS_ALIGNED(start | end, PAGE_SIZE) && + blocksize < PAGE_SIZE && start < inode->i_size) { + loff_t page_boundary = round_up(start, PAGE_SIZE); + + ext4_truncate_folio(inode, start, min(page_boundary, end)); + if (end > page_boundary) + ext4_truncate_folio(inode, + round_down(end, PAGE_SIZE), end); + } + +truncate_pagecache: + truncate_pagecache_range(inode, start, end - 1); + return 0; +} + static void ext4_wait_dax_page(struct inode *inode) { filemap_invalidate_unlock(inode->i_mapping); |