Merge tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-tracegrafted

Pull tracing fixes from Steven Rostedt:

 - Fix error output of boot instance creation failure

   Currently if a boot instance creation fails, instead of printing out
   the name of the instance that failed, it prints "(null)". That is
   because it prints "cur_str" that had already been processed by
   strsep(). Print the saved name instead.

   While at it, print the error code of the failure.

 - Fix use-after-free for same named historgrams

   Histograms can be named so that they can be used in multiple events.
   But if the named histogram has a variable attached, the second event
   that uses the named histogram which duplicates it and needs to free
   the original after duplication leaves the old variable in place and
   still visible. If another histogram uses than variable, it will use
   the stale one which will try to reference the freed duplicate
   histogram and crash the kernel.

   Free the duplicate variables along with the duplicated histogram
   data.

 - Check return value of kthread_run() in event self test

   The events self tests uses a kthread for testing but does not check
   if it succeeded in creating a kthread. If the kthread creation were
   to fail, the code will still try to call kthread_stop() on the error
   returned.

 - Fix race between reading trace_pipe and updating subbuffer size

   If a user is reading the trace_pipe file at the same time they update
   the ring buffer sub-buffer size, can cause the trace_pipe read to
   read stale data. Add trace_access_lock() around updating the ring
   buffer sub-buffer size.

 - Fix eventfs_inode on failure path in creation of the events directory

   In the creation of the "events" directory, if after allocating the
   eventfs_inode a failure is detected, it calls cleanup_ei() which
   calls free_ei(). The free_ei() will test if eventfs_inode being freed
   has no children. It is a bug if it does. But on the failure case of
   the creation of the "events" directory, the children lists have not
   yet been initialized and the free will trigger a warning because
   list_empty() on an uninitialized list returns false.

   Move the initialization into init_ei() where it makes more sense and
   makes sure that a created eventfs_inode has its lists initialized
   upon creation.

 - Check return value of kthread_run() in ftrace direct sample code

   The sample code that shows how to use the ftrace direct calls does
   not test the return of kthread_run() to see if it succeeds. Return a
   failure if the kthread_run() doesn't succeed.

 - Clear user events state on fork in case of alloc failure

   On fork, the child gets a pointer to the parent's user events state.
   It makes a copy of it then updates the child's pointer to it. But if
   the allocation fails, the duplication function leaves the child with
   a pointer to its parent's descriptor. When the child cleans up its
   data, it will free the parent's descriptor while the parent is still
   using it.

   In the duplication function, set the child's user_event_mm to NULL
   before testing if the allocation succeeded, and when it exits it will
   not free the parent's descriptor.

 - Fix retry exhaustion in simple ring buffer reader swap

   simple_ring_buffer_swap_reader_page() starts with retry set to 8 and
   post-decrements it only after a failed link replacement. On the final
   attempt, a successful replacement leaves retry at zero, while a
   failed replacement leaves it at -1.

   But the check for success expects the retry value to be non-zero and
   exits with an error on zero. This is the opposite result. Fix it.

 - Fail nicely when the remote swap_reader_page() returns an error

   Currently, if the swap_reader_page() of a remote buffer fails, it
   triggers a WARN_ON_ONCE() and continues normally. Instead, have it
   exit with an error and a pr_warn() print instead of a full WARNING.

* tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  ring-buffer: Stop remote reader update when page swap fails
  tracing: Fix retry exhaustion in simple ring buffer reader swap
  tracing/user_events: Clear copied tracing state before fork duplication
  samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-multi-modify
  samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-modify
  eventfs: Initialize ei->children and ei->list in init_ei()
  tracing: Fix use-after-free in trace_pipe read on sub-buffer order change
  tracing: Fix crash passing ERR_PTR to kthread_stop()
  tracing: Fix use-after-free with same-name named triggers
  tracing: Fix logged instance name on creation failure

1 files changed, 744 insertions, 0 deletions

diff --git a/fs/udf/balloc.c b/fs/udf/balloc.c
new file mode 100644
index 000000000..30cec5600
--- /dev/null
+++ b/fs/udf/balloc.c
@@ -0,0 +1,744 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * balloc.c
+ *
+ * PURPOSE
+ *	Block allocation handling routines for the OSTA-UDF(tm) filesystem.
+ *
+ * COPYRIGHT
+ *  (C) 1999-2001 Ben Fennema
+ *  (C) 1999 Stelias Computing Inc
+ *
+ * HISTORY
+ *
+ *  02/24/99 blf  Created.
+ *
+ */
+
+#include "udfdecl.h"
+
+#include <linux/bitops.h>
+#include <linux/overflow.h>
+
+#include "udf_i.h"
+#include "udf_sb.h"
+
+#define udf_clear_bit	__test_and_clear_bit_le
+#define udf_set_bit	__test_and_set_bit_le
+#define udf_test_bit	test_bit_le
+#define udf_find_next_one_bit	find_next_bit_le
+
+static int read_block_bitmap(struct super_block *sb,
+			     struct udf_bitmap *bitmap, unsigned int block,
+			     unsigned long bitmap_nr)
+{
+	struct buffer_head *bh = NULL;
+	int i;
+	int max_bits, off, count;
+	struct kernel_lb_addr loc;
+
+	loc.logicalBlockNum = bitmap->s_extPosition;
+	loc.partitionReferenceNum = UDF_SB(sb)->s_partition;
+
+	bh = sb_bread(sb, udf_get_lb_pblock(sb, &loc, block));
+	bitmap->s_block_bitmap[bitmap_nr] = bh;
+	if (!bh)
+		return -EIO;
+
+	/* Check consistency of Space Bitmap buffer. */
+	max_bits = sb->s_blocksize * 8;
+	if (!bitmap_nr) {
+		off = sizeof(struct spaceBitmapDesc) << 3;
+		count = min(max_bits - off, bitmap->s_nr_groups);
+	} else {
+		/*
+		 * Rough check if bitmap number is too big to have any bitmap
+ 		 * blocks reserved.
+		 */
+		if (bitmap_nr >
+		    (bitmap->s_nr_groups >> (sb->s_blocksize_bits + 3)) + 2)
+			return 0;
+		off = 0;
+		count = bitmap->s_nr_groups - bitmap_nr * max_bits +
+				(sizeof(struct spaceBitmapDesc) << 3);
+		count = min(count, max_bits);
+	}
+
+	for (i = 0; i < count; i++)
+		if (udf_test_bit(i + off, bh->b_data)) {
+			bitmap->s_block_bitmap[bitmap_nr] =
+							ERR_PTR(-EFSCORRUPTED);
+			brelse(bh);
+			return -EFSCORRUPTED;
+		}
+	return 0;
+}
+
+static int load_block_bitmap(struct super_block *sb,
+			     struct udf_bitmap *bitmap,
+			     unsigned int block_group)
+{
+	int retval = 0;
+	int nr_groups = bitmap->s_nr_groups;
+
+	if (block_group >= nr_groups) {
+		udf_debug("block_group (%u) >= nr_groups (%d)\n",
+			  block_group, nr_groups);
+		return -EFSCORRUPTED;
+	}
+
+	if (bitmap->s_block_bitmap[block_group]) {
+		/*
+		 * The bitmap failed verification in the past. No point in
+		 * trying again.
+		 */
+		if (IS_ERR(bitmap->s_block_bitmap[block_group]))
+			return PTR_ERR(bitmap->s_block_bitmap[block_group]);
+		return block_group;
+	}
+
+	retval = read_block_bitmap(sb, bitmap, block_group, block_group);
+	if (retval < 0)
+		return retval;
+
+	return block_group;
+}
+
+static void udf_add_free_space(struct super_block *sb, u16 partition, u32 cnt)
+{
+	struct udf_sb_info *sbi = UDF_SB(sb);
+	struct logicalVolIntegrityDesc *lvid;
+
+	if (!sbi->s_lvid_bh)
+		return;
+
+	lvid = (struct logicalVolIntegrityDesc *)sbi->s_lvid_bh->b_data;
+	le32_add_cpu(&lvid->freeSpaceTable[partition], cnt);
+	udf_updated_lvid(sb);
+}
+
+static void udf_bitmap_free_blocks(struct super_block *sb,
+				   struct udf_bitmap *bitmap,
+				   struct kernel_lb_addr *bloc,
+				   uint32_t offset,
+				   uint32_t count)
+{
+	struct udf_sb_info *sbi = UDF_SB(sb);
+	struct buffer_head *bh = NULL;
+	unsigned long block;
+	unsigned long block_group;
+	unsigned long bit;
+	unsigned long i;
+	int bitmap_nr;
+	unsigned long overflow;
+
+	mutex_lock(&sbi->s_alloc_mutex);
+	/* We make sure this cannot overflow when mounting the filesystem */
+	block = bloc->logicalBlockNum + offset +
+		(sizeof(struct spaceBitmapDesc) << 3);
+	do {
+		overflow = 0;
+		block_group = block >> (sb->s_blocksize_bits + 3);
+		bit = block % (sb->s_blocksize << 3);
+
+		/*
+		* Check to see if we are freeing blocks across a group boundary.
+		*/
+		if (bit + count > (sb->s_blocksize << 3)) {
+			overflow = bit + count - (sb->s_blocksize << 3);
+			count -= overflow;
+		}
+		bitmap_nr = load_block_bitmap(sb, bitmap, block_group);
+		if (bitmap_nr < 0)
+			goto error_return;
+
+		bh = bitmap->s_block_bitmap[bitmap_nr];
+		for (i = 0; i < count; i++) {
+			if (udf_set_bit(bit + i, bh->b_data)) {
+				udf_debug("bit %lu already set\n", bit + i);
+				udf_debug("byte=%2x\n",
+					  ((__u8 *)bh->b_data)[(bit + i) >> 3]);
+			}
+		}
+		udf_add_free_space(sb, sbi->s_partition, count);
+		mark_buffer_dirty(bh);
+		if (overflow) {
+			block += count;
+			count = overflow;
+		}
+	} while (overflow);
+
+error_return:
+	mutex_unlock(&sbi->s_alloc_mutex);
+}
+
+static int udf_bitmap_prealloc_blocks(struct super_block *sb,
+				      struct udf_bitmap *bitmap,
+				      uint16_t partition, uint32_t first_block,
+				      uint32_t block_count)
+{
+	struct udf_sb_info *sbi = UDF_SB(sb);
+	int alloc_count = 0;
+	int bit, block, block_group;
+	int bitmap_nr;
+	struct buffer_head *bh;
+	__u32 part_len;
+
+	mutex_lock(&sbi->s_alloc_mutex);
+	part_len = sbi->s_partmaps[partition].s_partition_len;
+	if (first_block >= part_len)
+		goto out;
+
+	if (first_block + block_count > part_len)
+		block_count = part_len - first_block;
+
+	do {
+		block = first_block + (sizeof(struct spaceBitmapDesc) << 3);
+		block_group = block >> (sb->s_blocksize_bits + 3);
+
+		bitmap_nr = load_block_bitmap(sb, bitmap, block_group);
+		if (bitmap_nr < 0)
+			goto out;
+		bh = bitmap->s_block_bitmap[bitmap_nr];
+
+		bit = block % (sb->s_blocksize << 3);
+
+		while (bit < (sb->s_blocksize << 3) && block_count > 0) {
+			if (!udf_clear_bit(bit, bh->b_data))
+				goto out;
+			block_count--;
+			alloc_count++;
+			bit++;
+			block++;
+		}
+		mark_buffer_dirty(bh);
+	} while (block_count > 0);
+
+out:
+	udf_add_free_space(sb, partition, -alloc_count);
+	mutex_unlock(&sbi->s_alloc_mutex);
+	return alloc_count;
+}
+
+static udf_pblk_t udf_bitmap_new_block(struct super_block *sb,
+				struct udf_bitmap *bitmap, uint16_t partition,
+				uint32_t goal, int *err)
+{
+	struct udf_sb_info *sbi = UDF_SB(sb);
+	int newbit, bit = 0;
+	udf_pblk_t block;
+	int block_group, group_start;
+	int end_goal, nr_groups, bitmap_nr, i;
+	struct buffer_head *bh = NULL;
+	char *ptr;
+	udf_pblk_t newblock = 0;
+
+	*err = -ENOSPC;
+	mutex_lock(&sbi->s_alloc_mutex);
+
+repeat:
+	if (goal >= sbi->s_partmaps[partition].s_partition_len)
+		goal = 0;
+
+	nr_groups = bitmap->s_nr_groups;
+	block = goal + (sizeof(struct spaceBitmapDesc) << 3);
+	block_group = block >> (sb->s_blocksize_bits + 3);
+	group_start = block_group ? 0 : sizeof(struct spaceBitmapDesc);
+
+	bitmap_nr = load_block_bitmap(sb, bitmap, block_group);
+	if (bitmap_nr < 0)
+		goto error_return;
+	bh = bitmap->s_block_bitmap[bitmap_nr];
+	ptr = memscan((char *)bh->b_data + group_start, 0xFF,
+		      sb->s_blocksize - group_start);
+
+	if ((ptr - ((char *)bh->b_data)) < sb->s_blocksize) {
+		bit = block % (sb->s_blocksize << 3);
+		if (udf_test_bit(bit, bh->b_data))
+			goto got_block;
+
+		end_goal = (bit + 63) & ~63;
+		bit = udf_find_next_one_bit(bh->b_data, end_goal, bit);
+		if (bit < end_goal)
+			goto got_block;
+
+		ptr = memscan((char *)bh->b_data + (bit >> 3), 0xFF,
+			      sb->s_blocksize - ((bit + 7) >> 3));
+		newbit = (ptr - ((char *)bh->b_data)) << 3;
+		if (newbit < sb->s_blocksize << 3) {
+			bit = newbit;
+			goto search_back;
+		}
+
+		newbit = udf_find_next_one_bit(bh->b_data,
+					       sb->s_blocksize << 3, bit);
+		if (newbit < sb->s_blocksize << 3) {
+			bit = newbit;
+			goto got_block;
+		}
+	}
+
+	for (i = 0; i < (nr_groups * 2); i++) {
+		block_group++;
+		if (block_group >= nr_groups)
+			block_group = 0;
+		group_start = block_group ? 0 : sizeof(struct spaceBitmapDesc);
+
+		bitmap_nr = load_block_bitmap(sb, bitmap, block_group);
+		if (bitmap_nr < 0)
+			goto error_return;
+		bh = bitmap->s_block_bitmap[bitmap_nr];
+		if (i < nr_groups) {
+			ptr = memscan((char *)bh->b_data + group_start, 0xFF,
+				      sb->s_blocksize - group_start);
+			if ((ptr - ((char *)bh->b_data)) < sb->s_blocksize) {
+				bit = (ptr - ((char *)bh->b_data)) << 3;
+				break;
+			}
+		} else {
+			bit = udf_find_next_one_bit(bh->b_data,
+						    sb->s_blocksize << 3,
+						    group_start << 3);
+			if (bit < sb->s_blocksize << 3)
+				break;
+		}
+	}
+	if (i >= (nr_groups * 2)) {
+		mutex_unlock(&sbi->s_alloc_mutex);
+		return newblock;
+	}
+	if (bit < sb->s_blocksize << 3)
+		goto search_back;
+	else
+		bit = udf_find_next_one_bit(bh->b_data, sb->s_blocksize << 3,
+					    group_start << 3);
+	if (bit >= sb->s_blocksize << 3) {
+		mutex_unlock(&sbi->s_alloc_mutex);
+		return 0;
+	}
+
+search_back:
+	i = 0;
+	while (i < 7 && bit > (group_start << 3) &&
+	       udf_test_bit(bit - 1, bh->b_data)) {
+		++i;
+		--bit;
+	}
+
+got_block:
+	newblock = bit + (block_group << (sb->s_blocksize_bits + 3)) -
+		(sizeof(struct spaceBitmapDesc) << 3);
+
+	if (newblock >= sbi->s_partmaps[partition].s_partition_len) {
+		/*
+		 * Ran off the end of the bitmap, and bits following are
+		 * non-compliant (not all zero)
+		 */
+		udf_err(sb, "bitmap for partition %d corrupted (block %u marked"
+			" as free, partition length is %u)\n", partition,
+			newblock, sbi->s_partmaps[partition].s_partition_len);
+		goto error_return;
+	}
+
+	if (!udf_clear_bit(bit, bh->b_data)) {
+		udf_debug("bit already cleared for block %d\n", bit);
+		goto repeat;
+	}
+
+	mark_buffer_dirty(bh);
+
+	udf_add_free_space(sb, partition, -1);
+	mutex_unlock(&sbi->s_alloc_mutex);
+	*err = 0;
+	return newblock;
+
+error_return:
+	*err = -EIO;
+	mutex_unlock(&sbi->s_alloc_mutex);
+	return 0;
+}
+
+static void udf_table_free_blocks(struct super_block *sb,
+				  struct inode *table,
+				  struct kernel_lb_addr *bloc,
+				  uint32_t offset,
+				  uint32_t count)
+{
+	struct udf_sb_info *sbi = UDF_SB(sb);
+	uint32_t start, end;
+	uint32_t elen;
+	struct kernel_lb_addr eloc;
+	struct extent_position oepos, epos;
+	int8_t etype;
+	struct udf_inode_info *iinfo;
+	int ret = 0;
+
+	mutex_lock(&sbi->s_alloc_mutex);
+	iinfo = UDF_I(table);
+	udf_add_free_space(sb, sbi->s_partition, count);
+
+	start = bloc->logicalBlockNum + offset;
+	end = bloc->logicalBlockNum + offset + count - 1;
+
+	epos.offset = oepos.offset = sizeof(struct unallocSpaceEntry);
+	elen = 0;
+	epos.block = oepos.block = iinfo->i_location;
+	epos.bh = oepos.bh = NULL;
+
+	while (count) {
+		ret = udf_next_aext(table, &epos, &eloc, &elen, &etype, 1);
+		if (ret < 0)
+			goto error_return;
+		if (ret == 0)
+			break;
+		if (((eloc.logicalBlockNum +
+			(elen >> sb->s_blocksize_bits)) == start)) {
+			if ((0x3FFFFFFF - elen) <
+					(count << sb->s_blocksize_bits)) {
+				uint32_t tmp = ((0x3FFFFFFF - elen) >>
+							sb->s_blocksize_bits);
+				count -= tmp;
+				start += tmp;
+				elen = (etype << 30) |
+					(0x40000000 - sb->s_blocksize);
+			} else {
+				elen = (etype << 30) |
+					(elen +
+					(count << sb->s_blocksize_bits));
+				start += count;
+				count = 0;
+			}
+			udf_write_aext(table, &oepos, &eloc, elen, 1);
+		} else if (eloc.logicalBlockNum == (end + 1)) {
+			if ((0x3FFFFFFF - elen) <
+					(count << sb->s_blocksize_bits)) {
+				uint32_t tmp = ((0x3FFFFFFF - elen) >>
+						sb->s_blocksize_bits);
+				count -= tmp;
+				end -= tmp;
+				eloc.logicalBlockNum -= tmp;
+				elen = (etype << 30) |
+					(0x40000000 - sb->s_blocksize);
+			} else {
+				eloc.logicalBlockNum = start;
+				elen = (etype << 30) |
+					(elen +
+					(count << sb->s_blocksize_bits));
+				end -= count;
+				count = 0;
+			}
+			udf_write_aext(table, &oepos, &eloc, elen, 1);
+		}
+
+		if (epos.bh != oepos.bh) {
+			oepos.block = epos.block;
+			brelse(oepos.bh);
+			get_bh(epos.bh);
+			oepos.bh = epos.bh;
+			oepos.offset = 0;
+		} else {
+			oepos.offset = epos.offset;
+		}
+	}
+
+	if (count) {
+		/*
+		 * NOTE: we CANNOT use udf_add_aext here, as it can try to
+		 * allocate a new block, and since we hold the super block
+		 * lock already very bad things would happen :)
+		 *
+		 * We copy the behavior of udf_add_aext, but instead of
+		 * trying to allocate a new block close to the existing one,
+		 * we just steal a block from the extent we are trying to add.
+		 *
+		 * It would be nice if the blocks were close together, but it
+		 * isn't required.
+		 */
+
+		int adsize;
+
+		eloc.logicalBlockNum = start;
+		elen = EXT_RECORDED_ALLOCATED |
+			(count << sb->s_blocksize_bits);
+
+		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
+			goto error_return;
+
+		if (epos.offset + (2 * adsize) > sb->s_blocksize) {
+			/* Steal a block from the extent being free'd */
+			udf_setup_indirect_aext(table, eloc.logicalBlockNum,
+						&epos);
+
+			eloc.logicalBlockNum++;
+			elen -= sb->s_blocksize;
+		}
+
+		/* It's possible that stealing the block emptied the extent */
+		if (elen)
+			__udf_add_aext(table, &epos, &eloc, elen, 1);
+	}
+
+error_return:
+	brelse(epos.bh);
+	brelse(oepos.bh);
+
+	mutex_unlock(&sbi->s_alloc_mutex);
+	return;
+}
+
+static int udf_table_prealloc_blocks(struct super_block *sb,
+				     struct inode *table, uint16_t partition,
+				     uint32_t first_block, uint32_t block_count)
+{
+	struct udf_sb_info *sbi = UDF_SB(sb);
+	int alloc_count = 0;
+	uint32_t elen, adsize;
+	struct kernel_lb_addr eloc;
+	struct extent_position epos;
+	int8_t etype = -1;
+	struct udf_inode_info *iinfo;
+	int ret = 0;
+	/* AED block freed by udf_delete_aext(), released after unlock */
+	struct kernel_lb_addr freed = { .partitionReferenceNum = 0xFFFF };
+
+	if (first_block >= sbi->s_partmaps[partition].s_partition_len)
+		return 0;
+
+	iinfo = UDF_I(table);
+	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
+		return 0;
+
+	mutex_lock(&sbi->s_alloc_mutex);
+	epos.offset = sizeof(struct unallocSpaceEntry);
+	epos.block = iinfo->i_location;
+	epos.bh = NULL;
+	eloc.logicalBlockNum = 0xFFFFFFFF;
+
+	while (first_block != eloc.logicalBlockNum) {
+		ret = udf_next_aext(table, &epos, &eloc, &elen, &etype, 1);
+		if (ret < 0)
+			goto err_out;
+		if (ret == 0)
+			break;
+		udf_debug("eloc=%u, elen=%u, first_block=%u\n",
+			  eloc.logicalBlockNum, elen, first_block);
+	}
+
+	if (first_block == eloc.logicalBlockNum) {
+		epos.offset -= adsize;
+
+		alloc_count = (elen >> sb->s_blocksize_bits);
+		if (alloc_count > block_count) {
+			alloc_count = block_count;
+			eloc.logicalBlockNum += alloc_count;
+			elen -= (alloc_count << sb->s_blocksize_bits);
+			udf_write_aext(table, &epos, &eloc,
+					(etype << 30) | elen, 1);
+		} else
+			udf_delete_aext(table, epos, &freed);
+	} else {
+		alloc_count = 0;
+	}
+
+err_out:
+	brelse(epos.bh);
+
+	if (alloc_count)
+		udf_add_free_space(sb, partition, -alloc_count);
+	mutex_unlock(&sbi->s_alloc_mutex);
+	if (freed.partitionReferenceNum != 0xFFFF)
+		udf_free_blocks(sb, table, &freed, 0, 1);
+	return alloc_count;
+}
+
+static udf_pblk_t udf_table_new_block(struct super_block *sb,
+			       struct inode *table, uint16_t partition,
+			       uint32_t goal, int *err)
+{
+	struct udf_sb_info *sbi = UDF_SB(sb);
+	/* AED block freed by udf_delete_aext(), released after unlock */
+	struct kernel_lb_addr freed = { .partitionReferenceNum = 0xFFFF };
+	uint32_t spread = 0xFFFFFFFF, nspread = 0xFFFFFFFF;
+	udf_pblk_t newblock = 0;
+	uint32_t adsize;
+	uint32_t elen, goal_elen = 0;
+	struct kernel_lb_addr eloc, goal_eloc;
+	struct extent_position epos, goal_epos;
+	int8_t etype;
+	struct udf_inode_info *iinfo = UDF_I(table);
+	int ret = 0;
+
+	*err = -ENOSPC;
+
+	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
+		return newblock;
+
+	mutex_lock(&sbi->s_alloc_mutex);
+	if (goal >= sbi->s_partmaps[partition].s_partition_len)
+		goal = 0;
+
+	/* We search for the closest matching block to goal. If we find
+	   a exact hit, we stop. Otherwise we keep going till we run out
+	   of extents. We store the buffer_head, bloc, and extoffset
+	   of the current closest match and use that when we are done.
+	 */
+	epos.offset = sizeof(struct unallocSpaceEntry);
+	epos.block = iinfo->i_location;
+	epos.bh = goal_epos.bh = NULL;
+
+	while (spread) {
+		ret = udf_next_aext(table, &epos, &eloc, &elen, &etype, 1);
+		if (ret <= 0)
+			break;
+		if (goal >= eloc.logicalBlockNum) {
+			if (goal < eloc.logicalBlockNum +
+					(elen >> sb->s_blocksize_bits))
+				nspread = 0;
+			else
+				nspread = goal - eloc.logicalBlockNum -
+					(elen >> sb->s_blocksize_bits);
+		} else {
+			nspread = eloc.logicalBlockNum - goal;
+		}
+
+		if (nspread < spread) {
+			spread = nspread;
+			if (goal_epos.bh != epos.bh) {
+				brelse(goal_epos.bh);
+				goal_epos.bh = epos.bh;
+				get_bh(goal_epos.bh);
+			}
+			goal_epos.block = epos.block;
+			goal_epos.offset = epos.offset - adsize;
+			goal_eloc = eloc;
+			goal_elen = (etype << 30) | elen;
+		}
+	}
+
+	brelse(epos.bh);
+
+	if (ret < 0 || spread == 0xFFFFFFFF) {
+		brelse(goal_epos.bh);
+		mutex_unlock(&sbi->s_alloc_mutex);
+		if (ret < 0)
+			*err = ret;
+		return 0;
+	}
+
+	/* Only allocate blocks from the beginning of the extent.
+	   That way, we only delete (empty) extents, never have to insert an
+	   extent because of splitting */
+	/* This works, but very poorly.... */
+
+	newblock = goal_eloc.logicalBlockNum;
+	goal_eloc.logicalBlockNum++;
+	goal_elen -= sb->s_blocksize;
+
+	if (goal_elen)
+		udf_write_aext(table, &goal_epos, &goal_eloc, goal_elen, 1);
+	else
+		udf_delete_aext(table, goal_epos, &freed);
+	brelse(goal_epos.bh);
+
+	udf_add_free_space(sb, partition, -1);
+
+	mutex_unlock(&sbi->s_alloc_mutex);
+	if (freed.partitionReferenceNum != 0xFFFF)
+		udf_free_blocks(sb, table, &freed, 0, 1);
+	*err = 0;
+	return newblock;
+}
+
+void udf_free_blocks(struct super_block *sb, struct inode *inode,
+		     struct kernel_lb_addr *bloc, uint32_t offset,
+		     uint32_t count)
+{
+	uint16_t partition = bloc->partitionReferenceNum;
+	struct udf_part_map *map = &UDF_SB(sb)->s_partmaps[partition];
+	uint32_t blk;
+
+	if (check_add_overflow(bloc->logicalBlockNum, offset, &blk) ||
+	    check_add_overflow(blk, count, &blk) ||
+	    blk > map->s_partition_len) {
+		udf_debug("Invalid request to free blocks: (%d, %u), off %u, "
+			  "len %u, partition len %u\n",
+			  partition, bloc->logicalBlockNum, offset, count,
+			  map->s_partition_len);
+		return;
+	}
+
+	if (map->s_partition_flags & UDF_PART_FLAG_UNALLOC_BITMAP) {
+		udf_bitmap_free_blocks(sb, map->s_uspace.s_bitmap,
+				       bloc, offset, count);
+	} else if (map->s_partition_flags & UDF_PART_FLAG_UNALLOC_TABLE) {
+		udf_table_free_blocks(sb, map->s_uspace.s_table,
+				      bloc, offset, count);
+	}
+
+	if (inode) {
+		inode_sub_bytes(inode,
+				((sector_t)count) << sb->s_blocksize_bits);
+	}
+}
+
+inline int udf_prealloc_blocks(struct super_block *sb,
+			       struct inode *inode,
+			       uint16_t partition, uint32_t first_block,
+			       uint32_t block_count)
+{
+	struct udf_part_map *map = &UDF_SB(sb)->s_partmaps[partition];
+	int allocated;
+
+	if (map->s_partition_flags & UDF_PART_FLAG_UNALLOC_BITMAP)
+		allocated = udf_bitmap_prealloc_blocks(sb,
+						       map->s_uspace.s_bitmap,
+						       partition, first_block,
+						       block_count);
+	else if (map->s_partition_flags & UDF_PART_FLAG_UNALLOC_TABLE)
+		allocated = udf_table_prealloc_blocks(sb,
+						      map->s_uspace.s_table,
+						      partition, first_block,
+						      block_count);
+	else
+		return 0;
+
+	if (inode && allocated > 0)
+		inode_add_bytes(inode, allocated << sb->s_blocksize_bits);
+	return allocated;
+}
+
+inline udf_pblk_t udf_new_block(struct super_block *sb,
+			 struct inode *inode,
+			 uint16_t partition, uint32_t goal, int *err)
+{
+	struct udf_part_map *map = &UDF_SB(sb)->s_partmaps[partition];
+	udf_pblk_t block;
+
+	if (map->s_partition_flags & UDF_PART_FLAG_UNALLOC_BITMAP)
+		block = udf_bitmap_new_block(sb,
+					     map->s_uspace.s_bitmap,
+					     partition, goal, err);
+	else if (map->s_partition_flags & UDF_PART_FLAG_UNALLOC_TABLE)
+		block = udf_table_new_block(sb,
+					    map->s_uspace.s_table,
+					    partition, goal, err);
+	else {
+		*err = -EIO;
+		return 0;
+	}
+	if (inode && block)
+		inode_add_bytes(inode, sb->s_blocksize);
+	return block;
+}