Merge tag 'vfs-6.12.fallocate' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

Pull vfs fallocate updates from Christian Brauner:
 "This contains work to try and cleanup some the fallocate mode
  handling. Currently, it confusingly mixes operation modes and an
  optional flag.

  The work here tries to better define operation modes and optional
  flags allowing the core and filesystem code to use switch statements
  to switch on the operation mode"

* tag 'vfs-6.12.fallocate' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
  xfs: refactor xfs_file_fallocate
  xfs: move the xfs_is_always_cow_inode check into xfs_alloc_file_space
  xfs: call xfs_flush_unmap_range from xfs_free_file_space
  fs: sort out the fallocate mode vs flag mess
  ext4: remove tracing for FALLOC_FL_NO_HIDE_STALE
  block: remove checks for FALLOC_FL_NO_HIDE_STALE

2 files changed, 219 insertions, 145 deletions

diff --git a/fs/xfs/xfs_bmap_util.c b/fs/xfs/xfs_bmap_util.c
index fe2e2c930975..e9fdebaa40ea 100644
--- a/fs/xfs/xfs_bmap_util.c
+++ b/fs/xfs/xfs_bmap_util.c
@@ -653,6 +653,9 @@ xfs_alloc_file_space(
 	xfs_bmbt_irec_t		imaps[1], *imapp;
 	int			error;
 
+	if (xfs_is_always_cow_inode(ip))
+		return 0;
+
 	trace_xfs_alloc_file_space(ip);
 
 	if (xfs_is_shutdown(mp))
@@ -848,6 +851,14 @@ xfs_free_file_space(
 	if (len <= 0)	/* if nothing being freed */
 		return 0;
 
+	/*
+	 * Now AIO and DIO has drained we flush and (if necessary) invalidate
+	 * the cached range over the first operation we are about to run.
+	 */
+	error = xfs_flush_unmap_range(ip, offset, len);
+	if (error)
+		return error;
+
 	startoffset_fsb = XFS_B_TO_FSB(mp, offset);
 	endoffset_fsb = XFS_B_TO_FSBT(mp, offset + len);
 
diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c
index 4cdc54dc9686..f6e4912769a0 100644
--- a/fs/xfs/xfs_file.c
+++ b/fs/xfs/xfs_file.c
@@ -852,6 +852,192 @@ static inline bool xfs_file_sync_writes(struct file *filp)
 	return false;
 }
 
+static int
+xfs_falloc_newsize(
+	struct file		*file,
+	int			mode,
+	loff_t			offset,
+	loff_t			len,
+	loff_t			*new_size)
+{
+	struct inode		*inode = file_inode(file);
+
+	if ((mode & FALLOC_FL_KEEP_SIZE) || offset + len <= i_size_read(inode))
+		return 0;
+	*new_size = offset + len;
+	return inode_newsize_ok(inode, *new_size);
+}
+
+static int
+xfs_falloc_setsize(
+	struct file		*file,
+	loff_t			new_size)
+{
+	struct iattr iattr = {
+		.ia_valid	= ATTR_SIZE,
+		.ia_size	= new_size,
+	};
+
+	if (!new_size)
+		return 0;
+	return xfs_vn_setattr_size(file_mnt_idmap(file), file_dentry(file),
+			&iattr);
+}
+
+static int
+xfs_falloc_collapse_range(
+	struct file		*file,
+	loff_t			offset,
+	loff_t			len)
+{
+	struct inode		*inode = file_inode(file);
+	loff_t			new_size = i_size_read(inode) - len;
+	int			error;
+
+	if (!xfs_is_falloc_aligned(XFS_I(inode), offset, len))
+		return -EINVAL;
+
+	/*
+	 * There is no need to overlap collapse range with EOF, in which case it
+	 * is effectively a truncate operation
+	 */
+	if (offset + len >= i_size_read(inode))
+		return -EINVAL;
+
+	error = xfs_collapse_file_space(XFS_I(inode), offset, len);
+	if (error)
+		return error;
+	return xfs_falloc_setsize(file, new_size);
+}
+
+static int
+xfs_falloc_insert_range(
+	struct file		*file,
+	loff_t			offset,
+	loff_t			len)
+{
+	struct inode		*inode = file_inode(file);
+	loff_t			isize = i_size_read(inode);
+	int			error;
+
+	if (!xfs_is_falloc_aligned(XFS_I(inode), offset, len))
+		return -EINVAL;
+
+	/*
+	 * New inode size must not exceed ->s_maxbytes, accounting for
+	 * possible signed overflow.
+	 */
+	if (inode->i_sb->s_maxbytes - isize < len)
+		return -EFBIG;
+
+	/* Offset should be less than i_size */
+	if (offset >= isize)
+		return -EINVAL;
+
+	error = xfs_falloc_setsize(file, isize + len);
+	if (error)
+		return error;
+
+	/*
+	 * Perform hole insertion now that the file size has been updated so
+	 * that if we crash during the operation we don't leave shifted extents
+	 * past EOF and hence losing access to the data that is contained within
+	 * them.
+	 */
+	return xfs_insert_file_space(XFS_I(inode), offset, len);
+}
+
+/*
+ * Punch a hole and prealloc the range.  We use a hole punch rather than
+ * unwritten extent conversion for two reasons:
+ *
+ *   1.) Hole punch handles partial block zeroing for us.
+ *   2.) If prealloc returns ENOSPC, the file range is still zero-valued by
+ *	 virtue of the hole punch.
+ */
+static int
+xfs_falloc_zero_range(
+	struct file		*file,
+	int			mode,
+	loff_t			offset,
+	loff_t			len)
+{
+	struct inode		*inode = file_inode(file);
+	unsigned int		blksize = i_blocksize(inode);
+	loff_t			new_size = 0;
+	int			error;
+
+	trace_xfs_zero_file_space(XFS_I(inode));
+
+	error = xfs_falloc_newsize(file, mode, offset, len, &new_size);
+	if (error)
+		return error;
+
+	error = xfs_free_file_space(XFS_I(inode), offset, len);
+	if (error)
+		return error;
+
+	len = round_up(offset + len, blksize) - round_down(offset, blksize);
+	offset = round_down(offset, blksize);
+	error = xfs_alloc_file_space(XFS_I(inode), offset, len);
+	if (error)
+		return error;
+	return xfs_falloc_setsize(file, new_size);
+}
+
+static int
+xfs_falloc_unshare_range(
+	struct file		*file,
+	int			mode,
+	loff_t			offset,
+	loff_t			len)
+{
+	struct inode		*inode = file_inode(file);
+	loff_t			new_size = 0;
+	int			error;
+
+	error = xfs_falloc_newsize(file, mode, offset, len, &new_size);
+	if (error)
+		return error;
+
+	error = xfs_reflink_unshare(XFS_I(inode), offset, len);
+	if (error)
+		return error;
+
+	error = xfs_alloc_file_space(XFS_I(inode), offset, len);
+	if (error)
+		return error;
+	return xfs_falloc_setsize(file, new_size);
+}
+
+static int
+xfs_falloc_allocate_range(
+	struct file		*file,
+	int			mode,
+	loff_t			offset,
+	loff_t			len)
+{
+	struct inode		*inode = file_inode(file);
+	loff_t			new_size = 0;
+	int			error;
+
+	/*
+	 * If always_cow mode we can't use preallocations and thus should not
+	 * create them.
+	 */
+	if (xfs_is_always_cow_inode(XFS_I(inode)))
+		return -EOPNOTSUPP;
+
+	error = xfs_falloc_newsize(file, mode, offset, len, &new_size);
+	if (error)
+		return error;
+
+	error = xfs_alloc_file_space(XFS_I(inode), offset, len);
+	if (error)
+		return error;
+	return xfs_falloc_setsize(file, new_size);
+}
+
 #define	XFS_FALLOC_FL_SUPPORTED						\
 		(FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE |		\
 		 FALLOC_FL_COLLAPSE_RANGE | FALLOC_FL_ZERO_RANGE |	\
@@ -868,8 +1054,6 @@ xfs_file_fallocate(
 	struct xfs_inode	*ip = XFS_I(inode);
 	long			error;
 	uint			iolock = XFS_IOLOCK_EXCL | XFS_MMAPLOCK_EXCL;
-	loff_t			new_size = 0;
-	bool			do_file_insert = false;
 
 	if (!S_ISREG(inode->i_mode))
 		return -EINVAL;
@@ -890,156 +1074,35 @@ xfs_file_fallocate(
 	 */
 	inode_dio_wait(inode);
 
-	/*
-	 * Now AIO and DIO has drained we flush and (if necessary) invalidate
-	 * the cached range over the first operation we are about to run.
-	 *
-	 * We care about zero and collapse here because they both run a hole
-	 * punch over the range first. Because that can zero data, and the range
-	 * of invalidation for the shift operations is much larger, we still do
-	 * the required flush for collapse in xfs_prepare_shift().
-	 *
-	 * Insert has the same range requirements as collapse, and we extend the
-	 * file first which can zero data. Hence insert has the same
-	 * flush/invalidate requirements as collapse and so they are both
-	 * handled at the right time by xfs_prepare_shift().
-	 */
-	if (mode & (FALLOC_FL_PUNCH_HOLE | FALLOC_FL_ZERO_RANGE |
-		    FALLOC_FL_COLLAPSE_RANGE)) {
-		error = xfs_flush_unmap_range(ip, offset, len);
-		if (error)
-			goto out_unlock;
-	}
-
 	error = file_modified(file);
 	if (error)
 		goto out_unlock;
 
-	if (mode & FALLOC_FL_PUNCH_HOLE) {
+	switch (mode & FALLOC_FL_MODE_MASK) {
+	case FALLOC_FL_PUNCH_HOLE:
 		error = xfs_free_file_space(ip, offset, len);
-		if (error)
-			goto out_unlock;
-	} else if (mode & FALLOC_FL_COLLAPSE_RANGE) {
-		if (!xfs_is_falloc_aligned(ip, offset, len)) {
-			error = -EINVAL;
-			goto out_unlock;
-		}
-
-		/*
-		 * There is no need to overlap collapse range with EOF,
-		 * in which case it is effectively a truncate operation
-		 */
-		if (offset + len >= i_size_read(inode)) {
-			error = -EINVAL;
-			goto out_unlock;
-		}
-
-		new_size = i_size_read(inode) - len;
-
-		error = xfs_collapse_file_space(ip, offset, len);
-		if (error)
-			goto out_unlock;
-	} else if (mode & FALLOC_FL_INSERT_RANGE) {
-		loff_t		isize = i_size_read(inode);
-
-		if (!xfs_is_falloc_aligned(ip, offset, len)) {
-			error = -EINVAL;
-			goto out_unlock;
-		}
-
-		/*
-		 * New inode size must not exceed ->s_maxbytes, accounting for
-		 * possible signed overflow.
-		 */
-		if (inode->i_sb->s_maxbytes - isize < len) {
-			error = -EFBIG;
-			goto out_unlock;
-		}
-		new_size = isize + len;
-
-		/* Offset should be less than i_size */
-		if (offset >= isize) {
-			error = -EINVAL;
-			goto out_unlock;
-		}
-		do_file_insert = true;
-	} else {
-		if (!(mode & FALLOC_FL_KEEP_SIZE) &&
-		    offset + len > i_size_read(inode)) {
-			new_size = offset + len;
-			error = inode_newsize_ok(inode, new_size);
-			if (error)
-				goto out_unlock;
-		}
-
-		if (mode & FALLOC_FL_ZERO_RANGE) {
-			/*
-			 * Punch a hole and prealloc the range.  We use a hole
-			 * punch rather than unwritten extent conversion for two
-			 * reasons:
-			 *
-			 *   1.) Hole punch handles partial block zeroing for us.
-			 *   2.) If prealloc returns ENOSPC, the file range is
-			 *       still zero-valued by virtue of the hole punch.
-			 */
-			unsigned int blksize = i_blocksize(inode);
-
-			trace_xfs_zero_file_space(ip);
-
-			error = xfs_free_file_space(ip, offset, len);
-			if (error)
-				goto out_unlock;
-
-			len = round_up(offset + len, blksize) -
-			      round_down(offset, blksize);
-			offset = round_down(offset, blksize);
-		} else if (mode & FALLOC_FL_UNSHARE_RANGE) {
-			error = xfs_reflink_unshare(ip, offset, len);
-			if (error)
-				goto out_unlock;
-		} else {
-			/*
-			 * If always_cow mode we can't use preallocations and
-			 * thus should not create them.
-			 */
-			if (xfs_is_always_cow_inode(ip)) {
-				error = -EOPNOTSUPP;
-				goto out_unlock;
-			}
-		}
-
-		if (!xfs_is_always_cow_inode(ip)) {
-			error = xfs_alloc_file_space(ip, offset, len);
-			if (error)
-				goto out_unlock;
-		}
-	}
-
-	/* Change file size if needed */
-	if (new_size) {
-		struct iattr iattr;
-
-		iattr.ia_valid = ATTR_SIZE;
-		iattr.ia_size = new_size;
-		error = xfs_vn_setattr_size(file_mnt_idmap(file),
-					    file_dentry(file), &iattr);
-		if (error)
-			goto out_unlock;
-	}
-
-	/*
-	 * Perform hole insertion now that the file size has been
-	 * updated so that if we crash during the operation we don't
-	 * leave shifted extents past EOF and hence losing access to
-	 * the data that is contained within them.
-	 */
-	if (do_file_insert) {
-		error = xfs_insert_file_space(ip, offset, len);
-		if (error)
-			goto out_unlock;
+		break;
+	case FALLOC_FL_COLLAPSE_RANGE:
+		error = xfs_falloc_collapse_range(file, offset, len);
+		break;
+	case FALLOC_FL_INSERT_RANGE:
+		error = xfs_falloc_insert_range(file, offset, len);
+		break;
+	case FALLOC_FL_ZERO_RANGE:
+		error = xfs_falloc_zero_range(file, mode, offset, len);
+		break;
+	case FALLOC_FL_UNSHARE_RANGE:
+		error = xfs_falloc_unshare_range(file, mode, offset, len);
+		break;
+	case FALLOC_FL_ALLOCATE_RANGE:
+		error = xfs_falloc_allocate_range(file, mode, offset, len);
+		break;
+	default:
+		error = -EOPNOTSUPP;
+		break;
 	}
 
-	if (xfs_file_sync_writes(file))
+	if (!error && xfs_file_sync_writes(file))
 		error = xfs_log_force_inode(ip);
 
 out_unlock: