udf: Convert UDF to new truncate calling sequence

Use new truncation sequence in UDF and fix up error handling in the code. Signed-off-by: Jan Kara <jack@suse.cz>
2010-10-22 00:30:26 +02:00
parent 4a508dd259
commit 7e49b6f248
4 changed files with 234 additions and 170 deletions
--- a/fs/udf/inode.c
+++ b/fs/udf/inode.c
@@ -73,14 +73,12 @@ void udf_evict_inode(struct inode *inode)
 	struct udf_inode_info *iinfo = UDF_I(inode);
 	int want_delete = 0;

-	truncate_inode_pages(&inode->i_data, 0);
-
 	if (!inode->i_nlink && !is_bad_inode(inode)) {
 		want_delete = 1;
-		inode->i_size = 0;
-		udf_truncate(inode);
+		udf_setsize(inode, 0);
 		udf_update_inode(inode, IS_SYNC(inode));
-	}
+	} else
+		truncate_inode_pages(&inode->i_data, 0);
 	invalidate_inode_buffers(inode);
 	end_writeback(inode);
 	if (iinfo->i_alloc_type != ICBTAG_FLAG_AD_IN_ICB &&
@@ -117,9 +115,18 @@ static int udf_write_begin(struct file *file, struct address_space *mapping,

 	ret = block_write_begin(mapping, pos, len, flags, pagep, udf_get_block);
 	if (unlikely(ret)) {
-		loff_t isize = mapping->host->i_size;
-		if (pos + len > isize)
-			vmtruncate(mapping->host, isize);
+		struct inode *inode = mapping->host;
+		struct udf_inode_info *iinfo = UDF_I(inode);
+		loff_t isize = inode->i_size;
+
+		if (pos + len > isize) {
+			truncate_pagecache(inode, pos + len, isize);
+			if (iinfo->i_alloc_type != ICBTAG_FLAG_AD_IN_ICB) {
+				down_write(&iinfo->i_data_sem);
+				udf_truncate_extents(inode);
+				up_write(&iinfo->i_data_sem);
+			}
+		}
 	}

 	return ret;
@@ -139,30 +146,31 @@ const struct address_space_operations udf_aops = {
 	.bmap		= udf_bmap,
 };

-void udf_expand_file_adinicb(struct inode *inode, int newsize, int *err)
+int udf_expand_file_adinicb(struct inode *inode)
 {
 	struct page *page;
 	char *kaddr;
 	struct udf_inode_info *iinfo = UDF_I(inode);
+	int err;
 	struct writeback_control udf_wbc = {
 		.sync_mode = WB_SYNC_NONE,
 		.nr_to_write = 1,
 	};

-	/* from now on we have normal address_space methods */
-	inode->i_data.a_ops = &udf_aops;
-
 	if (!iinfo->i_lenAlloc) {
 		if (UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_USE_SHORT_AD))
 			iinfo->i_alloc_type = ICBTAG_FLAG_AD_SHORT;
 		else
 			iinfo->i_alloc_type = ICBTAG_FLAG_AD_LONG;
+		/* from now on we have normal address_space methods */
+		inode->i_data.a_ops = &udf_aops;
 		mark_inode_dirty(inode);
-		return;
+		return 0;
 	}

-	page = grab_cache_page(inode->i_mapping, 0);
-	BUG_ON(!PageLocked(page));
+	page = find_or_create_page(inode->i_mapping, 0, GFP_NOFS);
+	if (!page)
+		return -ENOMEM;

 	if (!PageUptodate(page)) {
 		kaddr = kmap(page);
@@ -181,11 +189,24 @@ void udf_expand_file_adinicb(struct inode *inode, int newsize, int *err)
 		iinfo->i_alloc_type = ICBTAG_FLAG_AD_SHORT;
 	else
 		iinfo->i_alloc_type = ICBTAG_FLAG_AD_LONG;
-
-	inode->i_data.a_ops->writepage(page, &udf_wbc);
+	/* from now on we have normal address_space methods */
+	inode->i_data.a_ops = &udf_aops;
+	err = inode->i_data.a_ops->writepage(page, &udf_wbc);
+	if (err) {
+		/* Restore everything back so that we don't lose data... */
+		lock_page(page);
+		kaddr = kmap(page);
+		memcpy(iinfo->i_ext.i_data + iinfo->i_lenEAttr, kaddr,
+		       inode->i_size);
+		kunmap(page);
+		unlock_page(page);
+		iinfo->i_alloc_type = ICBTAG_FLAG_AD_IN_ICB;
+		inode->i_data.a_ops = &udf_adinicb_aops;
+	}
 	page_cache_release(page);
-
 	mark_inode_dirty(inode);
+
+	return err;
 }

 struct buffer_head *udf_expand_dir_adinicb(struct inode *inode, int *block,
@@ -348,8 +369,10 @@ static struct buffer_head *udf_getblk(struct inode *inode, long block,
 }

 /* Extend the file by 'blocks' blocks, return the number of extents added */
-int udf_extend_file(struct inode *inode, struct extent_position *last_pos,
-		    struct kernel_long_ad *last_ext, sector_t blocks)
+static int udf_do_extend_file(struct inode *inode,
+			      struct extent_position *last_pos,
+			      struct kernel_long_ad *last_ext,
+			      sector_t blocks)
 {
 	sector_t add;
 	int count = 0, fake = !(last_ext->extLength & UDF_EXTENT_LENGTH_MASK);
@@ -357,6 +380,7 @@ int udf_extend_file(struct inode *inode, struct extent_position *last_pos,
 	struct kernel_lb_addr prealloc_loc = {};
 	int prealloc_len = 0;
 	struct udf_inode_info *iinfo;
+	int err;

 	/* The previous extent is fake and we should not extend by anything
 	 * - there's nothing to do... */
@@ -422,26 +446,29 @@ int udf_extend_file(struct inode *inode, struct extent_position *last_pos,
 	/* Create enough extents to cover the whole hole */
 	while (blocks > add) {
 		blocks -= add;
-		if (udf_add_aext(inode, last_pos, &last_ext->extLocation,
-				 last_ext->extLength, 1) == -1)
-			return -1;
+		err = udf_add_aext(inode, last_pos, &last_ext->extLocation,
+				   last_ext->extLength, 1);
+		if (err)
+			return err;
 		count++;
 	}
 	if (blocks) {
 		last_ext->extLength = EXT_NOT_RECORDED_NOT_ALLOCATED |
 			(blocks << sb->s_blocksize_bits);
-		if (udf_add_aext(inode, last_pos, &last_ext->extLocation,
-				 last_ext->extLength, 1) == -1)
-			return -1;
+		err = udf_add_aext(inode, last_pos, &last_ext->extLocation,
+				   last_ext->extLength, 1);
+		if (err)
+			return err;
 		count++;
 	}

 out:
 	/* Do we have some preallocated blocks saved? */
 	if (prealloc_len) {
-		if (udf_add_aext(inode, last_pos, &prealloc_loc,
-				 prealloc_len, 1) == -1)
-			return -1;
+		err = udf_add_aext(inode, last_pos, &prealloc_loc,
+				   prealloc_len, 1);
+		if (err)
+			return err;
 		last_ext->extLocation = prealloc_loc;
 		last_ext->extLength = prealloc_len;
 		count++;
@@ -453,11 +480,68 @@ out:
 	else if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG)
 		last_pos->offset -= sizeof(struct long_ad);
 	else
-		return -1;
+		return -EIO;

 	return count;
 }

+static int udf_extend_file(struct inode *inode, loff_t newsize)
+{
+
+	struct extent_position epos;
+	struct kernel_lb_addr eloc;
+	uint32_t elen;
+	int8_t etype;
+	struct super_block *sb = inode->i_sb;
+	sector_t first_block = newsize >> sb->s_blocksize_bits, offset;
+	int adsize;
+	struct udf_inode_info *iinfo = UDF_I(inode);
+	struct kernel_long_ad extent;
+	int err;
+
+	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
+		adsize = sizeof(struct short_ad);
+	else if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG)
+		adsize = sizeof(struct long_ad);
+	else
+		BUG();
+
+	etype = inode_bmap(inode, first_block, &epos, &eloc, &elen, &offset);
+
+	/* File has extent covering the new size (could happen when extending
+	 * inside a block)? */
+	if (etype != -1)
+		return 0;
+	if (newsize & (sb->s_blocksize - 1))
+		offset++;
+	/* Extended file just to the boundary of the last file block? */
+	if (offset == 0)
+		return 0;
+
+	/* Truncate is extending the file by 'offset' blocks */
+	if ((!epos.bh && epos.offset == udf_file_entry_alloc_offset(inode)) ||
+	    (epos.bh && epos.offset == sizeof(struct allocExtDesc))) {
+		/* File has no extents at all or has empty last
+		 * indirect extent! Create a fake extent... */
+		extent.extLocation.logicalBlockNum = 0;
+		extent.extLocation.partitionReferenceNum = 0;
+		extent.extLength = EXT_NOT_RECORDED_NOT_ALLOCATED;
+	} else {
+		epos.offset -= adsize;
+		etype = udf_next_aext(inode, &epos, &extent.extLocation,
+				      &extent.extLength, 0);
+		extent.extLength |= etype << 30;
+	}
+	err = udf_do_extend_file(inode, &epos, &extent, offset);
+	if (err < 0)
+		goto out;
+	err = 0;
+	iinfo->i_lenExtents = newsize;
+out:
+	brelse(epos.bh);
+	return err;
+}
+
 static struct buffer_head *inode_getblk(struct inode *inode, sector_t block,
 					int *err, sector_t *phys, int *new)
 {
@@ -540,7 +624,7 @@ static struct buffer_head *inode_getblk(struct inode *inode, sector_t block,
 			elen = EXT_RECORDED_ALLOCATED |
 				((elen + inode->i_sb->s_blocksize - 1) &
 				 ~(inode->i_sb->s_blocksize - 1));
-			etype = udf_write_aext(inode, &cur_epos, &eloc, elen, 1);
+			udf_write_aext(inode, &cur_epos, &eloc, elen, 1);
 		}
 		brelse(prev_epos.bh);
 		brelse(cur_epos.bh);
@@ -564,19 +648,17 @@ static struct buffer_head *inode_getblk(struct inode *inode, sector_t block,
 			memset(&laarr[0].extLocation, 0x00,
 				sizeof(struct kernel_lb_addr));
 			laarr[0].extLength = EXT_NOT_RECORDED_NOT_ALLOCATED;
-			/* Will udf_extend_file() create real extent from
+			/* Will udf_do_extend_file() create real extent from
 			   a fake one? */
 			startnum = (offset > 0);
 		}
 		/* Create extents for the hole between EOF and offset */
-		ret = udf_extend_file(inode, &prev_epos, laarr, offset);
-		if (ret == -1) {
+		ret = udf_do_extend_file(inode, &prev_epos, laarr, offset);
+		if (ret < 0) {
 			brelse(prev_epos.bh);
 			brelse(cur_epos.bh);
 			brelse(next_epos.bh);
-			/* We don't really know the error here so we just make
-			 * something up */
-			*err = -ENOSPC;
+			*err = ret;
 			return NULL;
 		}
 		c = 0;
@@ -1005,52 +1087,66 @@ struct buffer_head *udf_bread(struct inode *inode, int block,
 	return NULL;
 }

-void udf_truncate(struct inode *inode)
+int udf_setsize(struct inode *inode, loff_t newsize)
 {
-	int offset;
 	int err;
 	struct udf_inode_info *iinfo;
+	int bsize = 1 << inode->i_blkbits;

 	if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
 	      S_ISLNK(inode->i_mode)))
-		return;
+		return -EINVAL;
 	if (IS_APPEND(inode) || IS_IMMUTABLE(inode))
-		return;
+		return -EPERM;

 	iinfo = UDF_I(inode);
-	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) {
+	if (newsize > inode->i_size) {
 		down_write(&iinfo->i_data_sem);
-		if (inode->i_sb->s_blocksize <
-				(udf_file_entry_alloc_offset(inode) +
-				 inode->i_size)) {
-			udf_expand_file_adinicb(inode, inode->i_size, &err);
-			if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) {
-				inode->i_size = iinfo->i_lenAlloc;
-				up_write(&iinfo->i_data_sem);
-				return;
+		if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) {
+			if (bsize <
+			    (udf_file_entry_alloc_offset(inode) + newsize)) {
+				err = udf_expand_file_adinicb(inode);
+				if (err) {
+					up_write(&iinfo->i_data_sem);
+					return err;
+				}
 			} else
-				udf_truncate_extents(inode);
-		} else {
-			offset = inode->i_size & (inode->i_sb->s_blocksize - 1);
-			memset(iinfo->i_ext.i_data + iinfo->i_lenEAttr + offset,
-				0x00, inode->i_sb->s_blocksize -
-				offset - udf_file_entry_alloc_offset(inode));
-			iinfo->i_lenAlloc = inode->i_size;
+				iinfo->i_lenAlloc = newsize;
 		}
+		err = udf_extend_file(inode, newsize);
+		if (err) {
+			up_write(&iinfo->i_data_sem);
+			return err;
+		}
+		truncate_setsize(inode, newsize);
 		up_write(&iinfo->i_data_sem);
 	} else {
-		block_truncate_page(inode->i_mapping, inode->i_size,
-				    udf_get_block);
+		if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) {
+			down_write(&iinfo->i_data_sem);
+			memset(iinfo->i_ext.i_data + iinfo->i_lenEAttr + newsize,
+			       0x00, bsize - newsize -
+			       udf_file_entry_alloc_offset(inode));
+			iinfo->i_lenAlloc = newsize;
+			truncate_setsize(inode, newsize);
+			up_write(&iinfo->i_data_sem);
+			goto update_time;
+		}
+		err = block_truncate_page(inode->i_mapping, newsize,
+					  udf_get_block);
+		if (err)
+			return err;
 		down_write(&iinfo->i_data_sem);
+		truncate_setsize(inode, newsize);
 		udf_truncate_extents(inode);
 		up_write(&iinfo->i_data_sem);
 	}
-
+update_time:
 	inode->i_mtime = inode->i_ctime = current_fs_time(inode->i_sb);
 	if (IS_SYNC(inode))
 		udf_sync_inode(inode);
 	else
 		mark_inode_dirty(inode);
+	return 0;
 }

 static void __udf_read_inode(struct inode *inode)
@@ -1637,14 +1733,13 @@ struct inode *udf_iget(struct super_block *sb, struct kernel_lb_addr *ino)
 	return NULL;
 }

-int8_t udf_add_aext(struct inode *inode, struct extent_position *epos,
-		    struct kernel_lb_addr *eloc, uint32_t elen, int inc)
+int udf_add_aext(struct inode *inode, struct extent_position *epos,
+		 struct kernel_lb_addr *eloc, uint32_t elen, int inc)
 {
 	int adsize;
 	struct short_ad *sad = NULL;
 	struct long_ad *lad = NULL;
 	struct allocExtDesc *aed;
-	int8_t etype;
 	uint8_t *ptr;
 	struct udf_inode_info *iinfo = UDF_I(inode);

@@ -1660,7 +1755,7 @@ int8_t udf_add_aext(struct inode *inode, struct extent_position *epos,
 	else if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG)
 		adsize = sizeof(struct long_ad);
 	else
-		return -1;
+		return -EIO;

 	if (epos->offset + (2 * adsize) > inode->i_sb->s_blocksize) {
 		unsigned char *sptr, *dptr;
@@ -1672,12 +1767,12 @@ int8_t udf_add_aext(struct inode *inode, struct extent_position *epos,
 						obloc.partitionReferenceNum,
 						obloc.logicalBlockNum, &err);
 		if (!epos->block.logicalBlockNum)
-			return -1;
+			return -ENOSPC;
 		nbh = udf_tgetblk(inode->i_sb, udf_get_lb_pblock(inode->i_sb,
 								 &epos->block,
 								 0));
 		if (!nbh)
-			return -1;
+			return -EIO;
 		lock_buffer(nbh);
 		memset(nbh->b_data, 0x00, inode->i_sb->s_blocksize);
 		set_buffer_uptodate(nbh);
@@ -1746,7 +1841,7 @@ int8_t udf_add_aext(struct inode *inode, struct extent_position *epos,
 		epos->bh = nbh;
 	}

-	etype = udf_write_aext(inode, epos, eloc, elen, inc);
+	udf_write_aext(inode, epos, eloc, elen, inc);

 	if (!epos->bh) {
 		iinfo->i_lenAlloc += adsize;
@@ -1764,11 +1859,11 @@ int8_t udf_add_aext(struct inode *inode, struct extent_position *epos,
 		mark_buffer_dirty_inode(epos->bh, inode);
 	}

-	return etype;
+	return 0;
 }

-int8_t udf_write_aext(struct inode *inode, struct extent_position *epos,
-		      struct kernel_lb_addr *eloc, uint32_t elen, int inc)
+void udf_write_aext(struct inode *inode, struct extent_position *epos,
+		    struct kernel_lb_addr *eloc, uint32_t elen, int inc)
 {
 	int adsize;
 	uint8_t *ptr;
@@ -1798,7 +1893,7 @@ int8_t udf_write_aext(struct inode *inode, struct extent_position *epos,
 		adsize = sizeof(struct long_ad);
 		break;
 	default:
-		return -1;
+		return;
 	}

 	if (epos->bh) {
@@ -1817,8 +1912,6 @@ int8_t udf_write_aext(struct inode *inode, struct extent_position *epos,

 	if (inc)
 		epos->offset += adsize;
-
-	return (elen >> 30);
 }

 int8_t udf_next_aext(struct inode *inode, struct extent_position *epos,