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, 636 insertions, 0 deletions

diff --git a/fs/hfsplus/extents.c b/fs/hfsplus/extents.c
new file mode 100644
index 000000000..eb7c11524
--- /dev/null
+++ b/fs/hfsplus/extents.c
@@ -0,0 +1,636 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ *  linux/fs/hfsplus/extents.c
+ *
+ * Copyright (C) 2001
+ * Brad Boyer (flar@allandria.com)
+ * (C) 2003 Ardis Technologies <roman@ardistech.com>
+ *
+ * Handling of Extents both in catalog and extents overflow trees
+ */
+
+#include <linux/errno.h>
+#include <linux/fs.h>
+#include <linux/pagemap.h>
+
+#include "hfsplus_fs.h"
+#include "hfsplus_raw.h"
+
+/* Compare two extents keys, returns 0 on same, pos/neg for difference */
+int hfsplus_ext_cmp_key(const hfsplus_btree_key *k1,
+			const hfsplus_btree_key *k2)
+{
+	__be32 k1id, k2id;
+	__be32 k1s, k2s;
+
+	k1id = k1->ext.cnid;
+	k2id = k2->ext.cnid;
+	if (k1id != k2id)
+		return be32_to_cpu(k1id) < be32_to_cpu(k2id) ? -1 : 1;
+
+	if (k1->ext.fork_type != k2->ext.fork_type)
+		return k1->ext.fork_type < k2->ext.fork_type ? -1 : 1;
+
+	k1s = k1->ext.start_block;
+	k2s = k2->ext.start_block;
+	if (k1s == k2s)
+		return 0;
+	return be32_to_cpu(k1s) < be32_to_cpu(k2s) ? -1 : 1;
+}
+
+static void hfsplus_ext_build_key(hfsplus_btree_key *key, u32 cnid,
+				  u32 block, u8 type)
+{
+	key->key_len = cpu_to_be16(HFSPLUS_EXT_KEYLEN - 2);
+	key->ext.cnid = cpu_to_be32(cnid);
+	key->ext.start_block = cpu_to_be32(block);
+	key->ext.fork_type = type;
+	key->ext.pad = 0;
+}
+
+static u32 hfsplus_ext_find_block(struct hfsplus_extent *ext, u32 off)
+{
+	int i;
+	u32 count;
+
+	for (i = 0; i < 8; ext++, i++) {
+		count = be32_to_cpu(ext->block_count);
+		if (off < count)
+			return be32_to_cpu(ext->start_block) + off;
+		off -= count;
+	}
+	/* panic? */
+	return 0;
+}
+
+static int hfsplus_ext_block_count(struct hfsplus_extent *ext)
+{
+	int i;
+	u32 count = 0;
+
+	for (i = 0; i < 8; ext++, i++)
+		count += be32_to_cpu(ext->block_count);
+	return count;
+}
+
+static u32 hfsplus_ext_lastblock(struct hfsplus_extent *ext)
+{
+	int i;
+
+	ext += 7;
+	for (i = 0; i < 7; ext--, i++)
+		if (ext->block_count)
+			break;
+	return be32_to_cpu(ext->start_block) + be32_to_cpu(ext->block_count);
+}
+
+static int __hfsplus_ext_write_extent(struct inode *inode,
+		struct hfs_find_data *fd)
+{
+	struct hfsplus_inode_info *hip = HFSPLUS_I(inode);
+	int res;
+
+	WARN_ON(!mutex_is_locked(&hip->extents_lock));
+
+	hfsplus_ext_build_key(fd->search_key, inode->i_ino, hip->cached_start,
+			      HFSPLUS_IS_RSRC(inode) ?
+				HFSPLUS_TYPE_RSRC : HFSPLUS_TYPE_DATA);
+
+	res = hfs_brec_find(fd, hfs_find_rec_by_key);
+	if (hip->extent_state & HFSPLUS_EXT_NEW) {
+		if (res != -ENOENT)
+			return res;
+		/* Fail early and avoid ENOSPC during the btree operation */
+		res = hfs_bmap_reserve(fd->tree, fd->tree->depth + 1);
+		if (res)
+			return res;
+		hfs_brec_insert(fd, hip->cached_extents,
+				sizeof(hfsplus_extent_rec));
+		hip->extent_state &= ~(HFSPLUS_EXT_DIRTY | HFSPLUS_EXT_NEW);
+	} else {
+		if (res)
+			return res;
+		if (fd->entrylength != sizeof(hfsplus_extent_rec))
+			return -EIO;
+		hfs_bnode_write(fd->bnode, hip->cached_extents,
+				fd->entryoffset, fd->entrylength);
+		hip->extent_state &= ~HFSPLUS_EXT_DIRTY;
+	}
+
+	/*
+	 * We can't just use hfsplus_mark_inode_dirty here, because we
+	 * also get called from hfsplus_write_inode, which should not
+	 * redirty the inode.  Instead the callers have to be careful
+	 * to explicily mark the inode dirty, too.
+	 */
+	set_bit(HFSPLUS_I_EXT_DIRTY,
+		&HFSPLUS_I(HFSPLUS_EXT_TREE_I(inode->i_sb))->flags);
+	set_bit(HFSPLUS_I_EXT_DIRTY, &hip->flags);
+
+	return 0;
+}
+
+static int hfsplus_ext_write_extent_locked(struct inode *inode)
+{
+	int res = 0;
+
+	if (HFSPLUS_I(inode)->extent_state & HFSPLUS_EXT_DIRTY) {
+		struct hfs_find_data fd;
+
+		res = hfs_find_init(HFSPLUS_SB(inode->i_sb)->ext_tree, &fd);
+		if (res)
+			return res;
+		res = __hfsplus_ext_write_extent(inode, &fd);
+		hfs_find_exit(&fd);
+	}
+	return res;
+}
+
+int hfsplus_ext_write_extent(struct inode *inode)
+{
+	int res;
+
+	mutex_lock(&HFSPLUS_I(inode)->extents_lock);
+	res = hfsplus_ext_write_extent_locked(inode);
+	mutex_unlock(&HFSPLUS_I(inode)->extents_lock);
+
+	return res;
+}
+
+static inline int __hfsplus_ext_read_extent(struct hfs_find_data *fd,
+					    struct hfsplus_extent *extent,
+					    u32 cnid, u32 block, u8 type)
+{
+	int res;
+
+	hfsplus_ext_build_key(fd->search_key, cnid, block, type);
+	fd->key->ext.cnid = 0;
+	res = hfs_brec_find(fd, hfs_find_rec_by_key);
+	if (res && res != -ENOENT)
+		return res;
+	if (fd->key->ext.cnid != fd->search_key->ext.cnid ||
+	    fd->key->ext.fork_type != fd->search_key->ext.fork_type)
+		return -ENOENT;
+	if (fd->entrylength != sizeof(hfsplus_extent_rec))
+		return -EIO;
+	hfs_bnode_read(fd->bnode, extent, fd->entryoffset,
+		sizeof(hfsplus_extent_rec));
+	return 0;
+}
+
+static inline int __hfsplus_ext_cache_extent(struct hfs_find_data *fd,
+		struct inode *inode, u32 block)
+{
+	struct hfsplus_inode_info *hip = HFSPLUS_I(inode);
+	int res;
+
+	WARN_ON(!mutex_is_locked(&hip->extents_lock));
+
+	if (hip->extent_state & HFSPLUS_EXT_DIRTY) {
+		res = __hfsplus_ext_write_extent(inode, fd);
+		if (res)
+			return res;
+	}
+
+	res = __hfsplus_ext_read_extent(fd, hip->cached_extents, inode->i_ino,
+					block, HFSPLUS_IS_RSRC(inode) ?
+						HFSPLUS_TYPE_RSRC :
+						HFSPLUS_TYPE_DATA);
+	if (!res) {
+		hip->cached_start = be32_to_cpu(fd->key->ext.start_block);
+		hip->cached_blocks =
+			hfsplus_ext_block_count(hip->cached_extents);
+	} else {
+		hip->cached_start = hip->cached_blocks = 0;
+		hip->extent_state &= ~(HFSPLUS_EXT_DIRTY | HFSPLUS_EXT_NEW);
+	}
+	return res;
+}
+
+static int hfsplus_ext_read_extent(struct inode *inode, u32 block)
+{
+	struct hfsplus_inode_info *hip = HFSPLUS_I(inode);
+	struct hfs_find_data fd;
+	int res;
+
+	if (block >= hip->cached_start &&
+	    block < hip->cached_start + hip->cached_blocks)
+		return 0;
+
+	res = hfs_find_init(HFSPLUS_SB(inode->i_sb)->ext_tree, &fd);
+	if (!res) {
+		res = __hfsplus_ext_cache_extent(&fd, inode, block);
+		hfs_find_exit(&fd);
+	}
+	return res;
+}
+
+/* Get a block at iblock for inode, possibly allocating if create */
+int hfsplus_get_block(struct inode *inode, sector_t iblock,
+		      struct buffer_head *bh_result, int create)
+{
+	struct super_block *sb = inode->i_sb;
+	struct hfsplus_sb_info *sbi = HFSPLUS_SB(sb);
+	struct hfsplus_inode_info *hip = HFSPLUS_I(inode);
+	int res = -EIO;
+	u32 ablock, dblock, mask;
+	sector_t sector;
+	int was_dirty = 0;
+
+	/* Convert inode block to disk allocation block */
+	ablock = iblock >> sbi->fs_shift;
+
+	if (iblock >= hip->fs_blocks) {
+		if (!create)
+			return 0;
+		if (iblock > hip->fs_blocks)
+			return -EIO;
+		if (ablock >= hip->alloc_blocks) {
+			res = hfsplus_file_extend(inode, false);
+			if (res)
+				return res;
+		}
+	} else
+		create = 0;
+
+	if (ablock < hip->first_blocks) {
+		dblock = hfsplus_ext_find_block(hip->first_extents, ablock);
+		goto done;
+	}
+
+	if (inode->i_ino == HFSPLUS_EXT_CNID)
+		return -EIO;
+
+	mutex_lock(&hip->extents_lock);
+
+	/*
+	 * hfsplus_ext_read_extent will write out a cached extent into
+	 * the extents btree.  In that case we may have to mark the inode
+	 * dirty even for a pure read of an extent here.
+	 */
+	was_dirty = (hip->extent_state & HFSPLUS_EXT_DIRTY);
+	res = hfsplus_ext_read_extent(inode, ablock);
+	if (res) {
+		mutex_unlock(&hip->extents_lock);
+		return -EIO;
+	}
+	dblock = hfsplus_ext_find_block(hip->cached_extents,
+					ablock - hip->cached_start);
+	mutex_unlock(&hip->extents_lock);
+
+done:
+	hfs_dbg("ino %llu, iblock %llu - dblock %u\n",
+		inode->i_ino, (long long)iblock, dblock);
+
+	mask = (1 << sbi->fs_shift) - 1;
+	sector = ((sector_t)dblock << sbi->fs_shift) +
+		  sbi->blockoffset + (iblock & mask);
+	map_bh(bh_result, sb, sector);
+
+	if (create) {
+		set_buffer_new(bh_result);
+		hip->phys_size += sb->s_blocksize;
+		hip->fs_blocks++;
+		inode_add_bytes(inode, sb->s_blocksize);
+	}
+	if (create || was_dirty)
+		mark_inode_dirty(inode);
+	return 0;
+}
+
+static void hfsplus_dump_extent(struct hfsplus_extent *extent)
+{
+	int i;
+
+	hfs_dbg("extent   ");
+	for (i = 0; i < 8; i++)
+		hfs_dbg(" start_block %u, block_count %u",
+			be32_to_cpu(extent[i].start_block),
+			be32_to_cpu(extent[i].block_count));
+	hfs_dbg("\n");
+}
+
+static int hfsplus_add_extent(struct hfsplus_extent *extent, u32 offset,
+			      u32 alloc_block, u32 block_count)
+{
+	u32 count, start;
+	int i;
+
+	hfsplus_dump_extent(extent);
+	for (i = 0; i < 8; extent++, i++) {
+		count = be32_to_cpu(extent->block_count);
+		if (offset == count) {
+			start = be32_to_cpu(extent->start_block);
+			if (alloc_block != start + count) {
+				if (++i >= 8)
+					return -ENOSPC;
+				extent++;
+				extent->start_block = cpu_to_be32(alloc_block);
+			} else
+				block_count += count;
+			extent->block_count = cpu_to_be32(block_count);
+			return 0;
+		} else if (offset < count)
+			break;
+		offset -= count;
+	}
+	/* panic? */
+	return -EIO;
+}
+
+static int hfsplus_free_extents(struct super_block *sb,
+				struct hfsplus_extent *extent,
+				u32 offset, u32 block_nr)
+{
+	u32 count, start;
+	int i;
+	int err = 0;
+
+	hfsplus_dump_extent(extent);
+	for (i = 0; i < 8; extent++, i++) {
+		count = be32_to_cpu(extent->block_count);
+		if (offset == count)
+			goto found;
+		else if (offset < count)
+			break;
+		offset -= count;
+	}
+	/* panic? */
+	return -EIO;
+found:
+	for (;;) {
+		start = be32_to_cpu(extent->start_block);
+		if (count <= block_nr) {
+			err = hfsplus_block_free(sb, start, count);
+			if (err) {
+				pr_err("can't free extent: start %u, count %u\n",
+					start, count);
+			}
+			extent->block_count = 0;
+			extent->start_block = 0;
+			block_nr -= count;
+		} else {
+			count -= block_nr;
+			err = hfsplus_block_free(sb, start + count, block_nr);
+			if (err) {
+				pr_err("can't free extent: start %u, count %u\n",
+					start, count);
+			}
+			extent->block_count = cpu_to_be32(count);
+			block_nr = 0;
+		}
+		if (!block_nr || !i) {
+			/*
+			 * Try to free all extents and
+			 * return only last error
+			 */
+			return err;
+		}
+		i--;
+		extent--;
+		count = be32_to_cpu(extent->block_count);
+	}
+}
+
+int hfsplus_free_fork(struct super_block *sb, u32 cnid,
+		struct hfsplus_fork_raw *fork, int type)
+{
+	struct hfs_find_data fd;
+	hfsplus_extent_rec ext_entry;
+	u32 total_blocks, blocks, start;
+	int res, i;
+
+	total_blocks = be32_to_cpu(fork->total_blocks);
+	if (!total_blocks)
+		return 0;
+
+	blocks = 0;
+	for (i = 0; i < 8; i++)
+		blocks += be32_to_cpu(fork->extents[i].block_count);
+
+	res = hfsplus_free_extents(sb, fork->extents, blocks, blocks);
+	if (res)
+		return res;
+	if (total_blocks == blocks)
+		return 0;
+
+	res = hfs_find_init(HFSPLUS_SB(sb)->ext_tree, &fd);
+	if (res)
+		return res;
+	do {
+		res = __hfsplus_ext_read_extent(&fd, ext_entry, cnid,
+						total_blocks, type);
+		if (res)
+			break;
+		start = be32_to_cpu(fd.key->ext.start_block);
+		hfs_brec_remove(&fd);
+
+		mutex_unlock(&fd.tree->tree_lock);
+		hfsplus_free_extents(sb, ext_entry, total_blocks - start,
+				     total_blocks);
+		total_blocks = start;
+		mutex_lock_nested(&fd.tree->tree_lock,
+			hfsplus_btree_lock_class(fd.tree));
+	} while (total_blocks > blocks);
+	hfs_find_exit(&fd);
+
+	return res;
+}
+
+int hfsplus_file_extend(struct inode *inode, bool zeroout)
+{
+	struct super_block *sb = inode->i_sb;
+	struct hfsplus_sb_info *sbi = HFSPLUS_SB(sb);
+	struct hfsplus_inode_info *hip = HFSPLUS_I(inode);
+	u32 start, len, goal;
+	int res;
+
+	if (sbi->alloc_file->i_size * 8 <
+	    sbi->total_blocks - sbi->free_blocks + 8) {
+		/* extend alloc file */
+		pr_err_ratelimited("extend alloc file! (%llu,%u,%u)\n",
+				   sbi->alloc_file->i_size * 8,
+				   sbi->total_blocks, sbi->free_blocks);
+		return -ENOSPC;
+	}
+
+	mutex_lock(&hip->extents_lock);
+	if (hip->alloc_blocks == hip->first_blocks)
+		goal = hfsplus_ext_lastblock(hip->first_extents);
+	else {
+		res = hfsplus_ext_read_extent(inode, hip->alloc_blocks);
+		if (res)
+			goto out;
+		goal = hfsplus_ext_lastblock(hip->cached_extents);
+	}
+
+	len = hip->clump_blocks;
+	start = hfsplus_block_allocate(sb, sbi->total_blocks, goal, &len);
+	if (start >= sbi->total_blocks) {
+		start = hfsplus_block_allocate(sb, goal, 0, &len);
+		if (start >= goal) {
+			res = -ENOSPC;
+			goto out;
+		}
+	}
+
+	if (zeroout) {
+		res = sb_issue_zeroout(sb, start, len, GFP_NOFS);
+		if (res)
+			goto out;
+	}
+
+	hfs_dbg("ino %llu, start %u, len %u\n", inode->i_ino, start, len);
+
+	if (hip->alloc_blocks <= hip->first_blocks) {
+		if (!hip->first_blocks) {
+			hfs_dbg("first_extent: start %u, len %u\n",
+				start, len);
+			/* no extents yet */
+			hip->first_extents[0].start_block = cpu_to_be32(start);
+			hip->first_extents[0].block_count = cpu_to_be32(len);
+			res = 0;
+		} else {
+			/* try to append to extents in inode */
+			res = hfsplus_add_extent(hip->first_extents,
+						 hip->alloc_blocks,
+						 start, len);
+			if (res == -ENOSPC)
+				goto insert_extent;
+		}
+		if (!res) {
+			hfsplus_dump_extent(hip->first_extents);
+			hip->first_blocks += len;
+		}
+	} else {
+		res = hfsplus_add_extent(hip->cached_extents,
+					 hip->alloc_blocks - hip->cached_start,
+					 start, len);
+		if (!res) {
+			hfsplus_dump_extent(hip->cached_extents);
+			hip->extent_state |= HFSPLUS_EXT_DIRTY;
+			hip->cached_blocks += len;
+		} else if (res == -ENOSPC)
+			goto insert_extent;
+	}
+out:
+	if (!res) {
+		hip->alloc_blocks += len;
+		mutex_unlock(&hip->extents_lock);
+		hfsplus_mark_inode_dirty(HFSPLUS_SB(sb)->alloc_file,
+					 HFSPLUS_I_ALLOC_DIRTY);
+		hfsplus_mark_inode_dirty(inode, HFSPLUS_I_ALLOC_DIRTY);
+		return 0;
+	}
+	mutex_unlock(&hip->extents_lock);
+	return res;
+
+insert_extent:
+	hfs_dbg("insert new extent\n");
+	res = hfsplus_ext_write_extent_locked(inode);
+	if (res)
+		goto out;
+
+	memset(hip->cached_extents, 0, sizeof(hfsplus_extent_rec));
+	hip->cached_extents[0].start_block = cpu_to_be32(start);
+	hip->cached_extents[0].block_count = cpu_to_be32(len);
+	hfsplus_dump_extent(hip->cached_extents);
+	hip->extent_state |= HFSPLUS_EXT_DIRTY | HFSPLUS_EXT_NEW;
+	hip->cached_start = hip->alloc_blocks;
+	hip->cached_blocks = len;
+
+	res = 0;
+	goto out;
+}
+
+void hfsplus_file_truncate(struct inode *inode)
+{
+	struct super_block *sb = inode->i_sb;
+	struct hfsplus_inode_info *hip = HFSPLUS_I(inode);
+	struct hfs_find_data fd;
+	u32 alloc_cnt, blk_cnt, start;
+	int res;
+
+	hfs_dbg("ino %llu, phys_size %llu -> i_size %llu\n",
+		inode->i_ino, (long long)hip->phys_size, inode->i_size);
+
+	if (inode->i_size > hip->phys_size) {
+		struct address_space *mapping = inode->i_mapping;
+		struct folio *folio;
+		void *fsdata = NULL;
+		loff_t size = inode->i_size;
+
+		res = hfsplus_write_begin(NULL, mapping, size, 0,
+					  &folio, &fsdata);
+		if (res)
+			return;
+		res = generic_write_end(NULL, mapping, size, 0, 0,
+					folio, fsdata);
+		if (res < 0)
+			return;
+		mark_inode_dirty(inode);
+		return;
+	} else if (inode->i_size == hip->phys_size)
+		return;
+
+	blk_cnt = (inode->i_size + HFSPLUS_SB(sb)->alloc_blksz - 1) >>
+			HFSPLUS_SB(sb)->alloc_blksz_shift;
+
+	mutex_lock(&hip->extents_lock);
+
+	alloc_cnt = hip->alloc_blocks;
+	if (blk_cnt == alloc_cnt)
+		goto out_unlock;
+
+	res = hfs_find_init(HFSPLUS_SB(sb)->ext_tree, &fd);
+	if (res) {
+		mutex_unlock(&hip->extents_lock);
+		/* XXX: We lack error handling of hfsplus_file_truncate() */
+		return;
+	}
+
+	while (1) {
+		if (alloc_cnt == hip->first_blocks) {
+			mutex_unlock(&fd.tree->tree_lock);
+			hfsplus_free_extents(sb, hip->first_extents,
+					     alloc_cnt, alloc_cnt - blk_cnt);
+			hfsplus_dump_extent(hip->first_extents);
+			hip->first_blocks = blk_cnt;
+			mutex_lock_nested(&fd.tree->tree_lock,
+				hfsplus_btree_lock_class(fd.tree));
+			break;
+		}
+		res = __hfsplus_ext_cache_extent(&fd, inode, alloc_cnt);
+		if (res)
+			break;
+
+		start = hip->cached_start;
+		if (blk_cnt <= start)
+			hfs_brec_remove(&fd);
+		mutex_unlock(&fd.tree->tree_lock);
+		hfsplus_free_extents(sb, hip->cached_extents,
+				     alloc_cnt - start, alloc_cnt - blk_cnt);
+		hfsplus_dump_extent(hip->cached_extents);
+		mutex_lock_nested(&fd.tree->tree_lock,
+				hfsplus_btree_lock_class(fd.tree));
+		if (blk_cnt > start) {
+			hip->extent_state |= HFSPLUS_EXT_DIRTY;
+			break;
+		}
+		alloc_cnt = start;
+		hip->cached_start = hip->cached_blocks = 0;
+		hip->extent_state &= ~(HFSPLUS_EXT_DIRTY | HFSPLUS_EXT_NEW);
+	}
+	hfs_find_exit(&fd);
+
+	hip->alloc_blocks = blk_cnt;
+out_unlock:
+	mutex_unlock(&hip->extents_lock);
+	hip->phys_size = inode->i_size;
+	hip->fs_blocks = (inode->i_size + sb->s_blocksize - 1) >>
+		sb->s_blocksize_bits;
+	inode_set_bytes(inode, hip->fs_blocks << sb->s_blocksize_bits);
+	hfsplus_mark_inode_dirty(HFSPLUS_SB(sb)->alloc_file,
+				 HFSPLUS_I_ALLOC_DIRTY);
+	hfsplus_mark_inode_dirty(inode, HFSPLUS_I_ALLOC_DIRTY);
+}