fs/ntfs3: Change new sparse cluster processing

Remove ntfs_sparse_cluster.
Zero clusters in attr_allocate_clusters.
Fixes xfstest generic/263

Signed-off-by: Konstantin Komarov <almaz.alexandrovich@paragon-software.com>

1 files changed, 33 insertions, 113 deletions

diff --git a/fs/ntfs3/file.c b/fs/ntfs3/file.c
index 96ba3f5a8470..63aef132e529 100644
--- a/fs/ntfs3/file.c
+++ b/fs/ntfs3/file.c
@@ -122,8 +122,8 @@ static int ntfs_extend_initialized_size(struct file *file,
 			bits = sbi->cluster_bits;
 			vcn = pos >> bits;
 
-			err = attr_data_get_block(ni, vcn, 0, &lcn, &clen,
-						  NULL);
+			err = attr_data_get_block(ni, vcn, 1, &lcn, &clen, NULL,
+						  false);
 			if (err)
 				goto out;
 
@@ -180,18 +180,18 @@ static int ntfs_zero_range(struct inode *inode, u64 vbo, u64 vbo_to)
 	struct address_space *mapping = inode->i_mapping;
 	u32 blocksize = 1 << inode->i_blkbits;
 	pgoff_t idx = vbo >> PAGE_SHIFT;
-	u32 z_start = vbo & (PAGE_SIZE - 1);
+	u32 from = vbo & (PAGE_SIZE - 1);
 	pgoff_t idx_end = (vbo_to + PAGE_SIZE - 1) >> PAGE_SHIFT;
 	loff_t page_off;
 	struct buffer_head *head, *bh;
-	u32 bh_next, bh_off, z_end;
+	u32 bh_next, bh_off, to;
 	sector_t iblock;
 	struct page *page;
 
-	for (; idx < idx_end; idx += 1, z_start = 0) {
+	for (; idx < idx_end; idx += 1, from = 0) {
 		page_off = (loff_t)idx << PAGE_SHIFT;
-		z_end = (page_off + PAGE_SIZE) > vbo_to ? (vbo_to - page_off)
-							: PAGE_SIZE;
+		to = (page_off + PAGE_SIZE) > vbo_to ? (vbo_to - page_off)
+						     : PAGE_SIZE;
 		iblock = page_off >> inode->i_blkbits;
 
 		page = find_or_create_page(mapping, idx,
@@ -208,7 +208,7 @@ static int ntfs_zero_range(struct inode *inode, u64 vbo, u64 vbo_to)
 		do {
 			bh_next = bh_off + blocksize;
 
-			if (bh_next <= z_start || bh_off >= z_end)
+			if (bh_next <= from || bh_off >= to)
 				continue;
 
 			if (!buffer_mapped(bh)) {
@@ -242,7 +242,7 @@ static int ntfs_zero_range(struct inode *inode, u64 vbo, u64 vbo_to)
 		} while (bh_off = bh_next, iblock += 1,
 			 head != (bh = bh->b_this_page));
 
-		zero_user_segment(page, z_start, z_end);
+		zero_user_segment(page, from, to);
 
 		unlock_page(page);
 		put_page(page);
@@ -254,80 +254,6 @@ out:
 }
 
 /*
- * ntfs_sparse_cluster - Helper function to zero a new allocated clusters.
- *
- * NOTE: 512 <= cluster size <= 2M
- */
-void ntfs_sparse_cluster(struct inode *inode, struct page *page0, CLST vcn,
-			 CLST len)
-{
-	struct address_space *mapping = inode->i_mapping;
-	struct ntfs_sb_info *sbi = inode->i_sb->s_fs_info;
-	u8 cluster_bits = sbi->cluster_bits;
-	u64 vbo = (u64)vcn << cluster_bits;
-	u64 bytes = (u64)len << cluster_bits;
-	u32 blocksize = 1 << inode->i_blkbits;
-	pgoff_t idx0 = page0 ? page0->index : -1;
-	loff_t vbo_clst = vbo & sbi->cluster_mask_inv;
-	loff_t end = ntfs_up_cluster(sbi, vbo + bytes);
-	pgoff_t idx = vbo_clst >> PAGE_SHIFT;
-	u32 from = vbo_clst & (PAGE_SIZE - 1);
-	pgoff_t idx_end = (end + PAGE_SIZE - 1) >> PAGE_SHIFT;
-	loff_t page_off;
-	u32 to;
-	bool partial;
-	struct page *page;
-
-	for (; idx < idx_end; idx += 1, from = 0) {
-		page = idx == idx0 ? page0 : grab_cache_page(mapping, idx);
-
-		if (!page)
-			continue;
-
-		page_off = (loff_t)idx << PAGE_SHIFT;
-		to = (page_off + PAGE_SIZE) > end ? (end - page_off)
-						  : PAGE_SIZE;
-		partial = false;
-
-		if ((from || PAGE_SIZE != to) &&
-		    likely(!page_has_buffers(page))) {
-			create_empty_buffers(page, blocksize, 0);
-		}
-
-		if (page_has_buffers(page)) {
-			struct buffer_head *head, *bh;
-			u32 bh_off = 0;
-
-			bh = head = page_buffers(page);
-			do {
-				u32 bh_next = bh_off + blocksize;
-
-				if (from <= bh_off && bh_next <= to) {
-					set_buffer_uptodate(bh);
-					mark_buffer_dirty(bh);
-				} else if (!buffer_uptodate(bh)) {
-					partial = true;
-				}
-				bh_off = bh_next;
-			} while (head != (bh = bh->b_this_page));
-		}
-
-		zero_user_segment(page, from, to);
-
-		if (!partial)
-			SetPageUptodate(page);
-		flush_dcache_page(page);
-		set_page_dirty(page);
-
-		if (idx != idx0) {
-			unlock_page(page);
-			put_page(page);
-		}
-		cond_resched();
-	}
-}
-
-/*
  * ntfs_file_mmap - file_operations::mmap
  */
 static int ntfs_file_mmap(struct file *file, struct vm_area_struct *vma)
@@ -368,13 +294,9 @@ static int ntfs_file_mmap(struct file *file, struct vm_area_struct *vma)
 
 			for (; vcn < end; vcn += len) {
 				err = attr_data_get_block(ni, vcn, 1, &lcn,
-							  &len, &new);
+							  &len, &new, true);
 				if (err)
 					goto out;
-
-				if (!new)
-					continue;
-				ntfs_sparse_cluster(inode, NULL, vcn, 1);
 			}
 		}
 
@@ -518,7 +440,8 @@ static long ntfs_fallocate(struct file *file, int mode, loff_t vbo, loff_t len)
 	struct ntfs_sb_info *sbi = sb->s_fs_info;
 	struct ntfs_inode *ni = ntfs_i(inode);
 	loff_t end = vbo + len;
-	loff_t vbo_down = round_down(vbo, PAGE_SIZE);
+	loff_t vbo_down = round_down(vbo, max_t(unsigned long,
+						sbi->cluster_size, PAGE_SIZE));
 	bool is_supported_holes = is_sparsed(ni) || is_compressed(ni);
 	loff_t i_size, new_size;
 	bool map_locked;
@@ -571,7 +494,8 @@ static long ntfs_fallocate(struct file *file, int mode, loff_t vbo, loff_t len)
 		u32 frame_size;
 		loff_t mask, vbo_a, end_a, tmp;
 
-		err = filemap_write_and_wait_range(mapping, vbo, LLONG_MAX);
+		err = filemap_write_and_wait_range(mapping, vbo_down,
+						   LLONG_MAX);
 		if (err)
 			goto out;
 
@@ -672,39 +596,35 @@ static long ntfs_fallocate(struct file *file, int mode, loff_t vbo, loff_t len)
 			goto out;
 
 		if (is_supported_holes) {
-			CLST vcn_v = bytes_to_cluster(sbi, ni->i_valid);
 			CLST vcn = vbo >> sbi->cluster_bits;
 			CLST cend = bytes_to_cluster(sbi, end);
+			CLST cend_v = bytes_to_cluster(sbi, ni->i_valid);
 			CLST lcn, clen;
 			bool new;
 
+			if (cend_v > cend)
+				cend_v = cend;
+
 			/*
-			 * Allocate but do not zero new clusters. (see below comments)
-			 * This breaks security: One can read unused on-disk areas.
+			 * Allocate and zero new clusters.
 			 * Zeroing these clusters may be too long.
-			 * Maybe we should check here for root rights?
+			 */
+			for (; vcn < cend_v; vcn += clen) {
+				err = attr_data_get_block(ni, vcn, cend_v - vcn,
+							  &lcn, &clen, &new,
+							  true);
+				if (err)
+					goto out;
+			}
+			/*
+			 * Allocate but not zero new clusters.
 			 */
 			for (; vcn < cend; vcn += clen) {
 				err = attr_data_get_block(ni, vcn, cend - vcn,
-							  &lcn, &clen, &new);
+							  &lcn, &clen, &new,
+							  false);
 				if (err)
 					goto out;
-				if (!new || vcn >= vcn_v)
-					continue;
-
-				/*
-				 * Unwritten area.
-				 * NTFS is not able to store several unwritten areas.
-				 * Activate 'ntfs_sparse_cluster' to zero new allocated clusters.
-				 *
-				 * Dangerous in case:
-				 * 1G of sparsed clusters + 1 cluster of data =>
-				 * valid_size == 1G + 1 cluster
-				 * fallocate(1G) will zero 1G and this can be very long
-				 * xfstest 016/086 will fail without 'ntfs_sparse_cluster'.
-				 */
-				ntfs_sparse_cluster(inode, NULL, vcn,
-						    min(vcn_v - vcn, clen));
 			}
 		}
 
@@ -925,8 +845,8 @@ static ssize_t ntfs_compress_write(struct kiocb *iocb, struct iov_iter *from)
 		frame_vbo = valid & ~(frame_size - 1);
 		off = valid & (frame_size - 1);
 
-		err = attr_data_get_block(ni, frame << NTFS_LZNT_CUNIT, 0, &lcn,
-					  &clen, NULL);
+		err = attr_data_get_block(ni, frame << NTFS_LZNT_CUNIT, 1, &lcn,
+					  &clen, NULL, false);
 		if (err)
 			goto out;