1 files changed, 134 insertions, 27 deletions

diff --git a/fs/xfs/xfs_iops.c b/fs/xfs/xfs_iops.c
index 207e0dadffc3..8cddbb7c149b 100644
--- a/fs/xfs/xfs_iops.c
+++ b/fs/xfs/xfs_iops.c
@@ -29,6 +29,7 @@
 #include "xfs_xattr.h"
 #include "xfs_file.h"
 #include "xfs_bmap.h"
+#include "xfs_zone_alloc.h"
 
 #include <linux/posix_acl.h>
 #include <linux/security.h>
@@ -298,14 +299,14 @@ xfs_vn_create(
 	return xfs_generic_create(idmap, dir, dentry, mode, 0, NULL);
 }
 
-STATIC int
+STATIC struct dentry *
 xfs_vn_mkdir(
 	struct mnt_idmap	*idmap,
 	struct inode		*dir,
 	struct dentry		*dentry,
 	umode_t			mode)
 {
-	return xfs_generic_create(idmap, dir, dentry, mode | S_IFDIR, 0, NULL);
+	return ERR_PTR(xfs_generic_create(idmap, dir, dentry, mode | S_IFDIR, 0, NULL));
 }
 
 STATIC struct dentry *
@@ -573,17 +574,109 @@ xfs_stat_blksize(
 }
 
 static void
-xfs_get_atomic_write_attr(
+xfs_report_dioalign(
 	struct xfs_inode	*ip,
-	unsigned int		*unit_min,
-	unsigned int		*unit_max)
+	struct kstat		*stat)
+{
+	struct xfs_buftarg	*target = xfs_inode_buftarg(ip);
+	struct block_device	*bdev = target->bt_bdev;
+
+	stat->result_mask |= STATX_DIOALIGN | STATX_DIO_READ_ALIGN;
+	stat->dio_mem_align = bdev_dma_alignment(bdev) + 1;
+
+	/*
+	 * For COW inodes, we can only perform out of place writes of entire
+	 * allocation units (blocks or RT extents).
+	 * For writes smaller than the allocation unit, we must fall back to
+	 * buffered I/O to perform read-modify-write cycles.  At best this is
+	 * highly inefficient; at worst it leads to page cache invalidation
+	 * races.  Tell applications to avoid this by reporting the larger write
+	 * alignment in dio_offset_align, and the smaller read alignment in
+	 * dio_read_offset_align.
+	 */
+	stat->dio_read_offset_align = bdev_logical_block_size(bdev);
+	if (xfs_is_cow_inode(ip))
+		stat->dio_offset_align = xfs_inode_alloc_unitsize(ip);
+	else
+		stat->dio_offset_align = stat->dio_read_offset_align;
+}
+
+unsigned int
+xfs_get_atomic_write_min(
+	struct xfs_inode	*ip)
+{
+	struct xfs_mount	*mp = ip->i_mount;
+
+	/*
+	 * If we can complete an atomic write via atomic out of place writes,
+	 * then advertise a minimum size of one fsblock.  Without this
+	 * mechanism, we can only guarantee atomic writes up to a single LBA.
+	 *
+	 * If out of place writes are not available, we can guarantee an atomic
+	 * write of exactly one single fsblock if the bdev will make that
+	 * guarantee for us.
+	 */
+	if (xfs_inode_can_hw_atomic_write(ip) || xfs_can_sw_atomic_write(mp))
+		return mp->m_sb.sb_blocksize;
+
+	return 0;
+}
+
+unsigned int
+xfs_get_atomic_write_max(
+	struct xfs_inode	*ip)
 {
-	if (!xfs_inode_can_atomicwrite(ip)) {
-		*unit_min = *unit_max = 0;
-		return;
+	struct xfs_mount	*mp = ip->i_mount;
+
+	/*
+	 * If out of place writes are not available, we can guarantee an atomic
+	 * write of exactly one single fsblock if the bdev will make that
+	 * guarantee for us.
+	 */
+	if (!xfs_can_sw_atomic_write(mp)) {
+		if (xfs_inode_can_hw_atomic_write(ip))
+			return mp->m_sb.sb_blocksize;
+		return 0;
 	}
 
-	*unit_min = *unit_max = ip->i_mount->m_sb.sb_blocksize;
+	/*
+	 * If we can complete an atomic write via atomic out of place writes,
+	 * then advertise a maximum size of whatever we can complete through
+	 * that means.  Hardware support is reported via max_opt, not here.
+	 */
+	if (XFS_IS_REALTIME_INODE(ip))
+		return XFS_FSB_TO_B(mp, mp->m_groups[XG_TYPE_RTG].awu_max);
+	return XFS_FSB_TO_B(mp, mp->m_groups[XG_TYPE_AG].awu_max);
+}
+
+unsigned int
+xfs_get_atomic_write_max_opt(
+	struct xfs_inode	*ip)
+{
+	unsigned int		awu_max = xfs_get_atomic_write_max(ip);
+
+	/* if the max is 1x block, then just keep behaviour that opt is 0 */
+	if (awu_max <= ip->i_mount->m_sb.sb_blocksize)
+		return 0;
+
+	/*
+	 * Advertise the maximum size of an atomic write that we can tell the
+	 * block device to perform for us.  In general the bdev limit will be
+	 * less than our out of place write limit, but we don't want to exceed
+	 * the awu_max.
+	 */
+	return min(awu_max, xfs_inode_buftarg(ip)->bt_bdev_awu_max);
+}
+
+static void
+xfs_report_atomic_write(
+	struct xfs_inode	*ip,
+	struct kstat		*stat)
+{
+	generic_fill_statx_atomic_writes(stat,
+			xfs_get_atomic_write_min(ip),
+			xfs_get_atomic_write_max(ip),
+			xfs_get_atomic_write_max_opt(ip));
 }
 
 STATIC int
@@ -647,22 +740,10 @@ xfs_vn_getattr(
 		stat->rdev = inode->i_rdev;
 		break;
 	case S_IFREG:
-		if (request_mask & STATX_DIOALIGN) {
-			struct xfs_buftarg	*target = xfs_inode_buftarg(ip);
-			struct block_device	*bdev = target->bt_bdev;
-
-			stat->result_mask |= STATX_DIOALIGN;
-			stat->dio_mem_align = bdev_dma_alignment(bdev) + 1;
-			stat->dio_offset_align = bdev_logical_block_size(bdev);
-		}
-		if (request_mask & STATX_WRITE_ATOMIC) {
-			unsigned int	unit_min, unit_max;
-
-			xfs_get_atomic_write_attr(ip, &unit_min,
-					&unit_max);
-			generic_fill_statx_atomic_writes(stat,
-					unit_min, unit_max);
-		}
+		if (request_mask & (STATX_DIOALIGN | STATX_DIO_READ_ALIGN))
+			xfs_report_dioalign(ip, stat);
+		if (request_mask & STATX_WRITE_ATOMIC)
+			xfs_report_atomic_write(ip, stat);
 		fallthrough;
 	default:
 		stat->blksize = xfs_stat_blksize(ip);
@@ -840,6 +921,7 @@ xfs_setattr_size(
 	uint			lock_flags = 0;
 	uint			resblks = 0;
 	bool			did_zeroing = false;
+	struct xfs_zone_alloc_ctx ac = { };
 
 	xfs_assert_ilocked(ip, XFS_IOLOCK_EXCL | XFS_MMAPLOCK_EXCL);
 	ASSERT(S_ISREG(inode->i_mode));
@@ -876,6 +958,28 @@ xfs_setattr_size(
 	inode_dio_wait(inode);
 
 	/*
+	 * Normally xfs_zoned_space_reserve is supposed to be called outside the
+	 * IOLOCK.  For truncate we can't do that since ->setattr is called with
+	 * it already held by the VFS.  So for now chicken out and try to
+	 * allocate space under it.
+	 *
+	 * To avoid deadlocks this means we can't block waiting for space, which
+	 * can lead to spurious -ENOSPC if there are no directly available
+	 * blocks.  We mitigate this a bit by allowing zeroing to dip into the
+	 * reserved pool, but eventually the VFS calling convention needs to
+	 * change.
+	 */
+	if (xfs_is_zoned_inode(ip)) {
+		error = xfs_zoned_space_reserve(ip, 1,
+				XFS_ZR_NOWAIT | XFS_ZR_RESERVED, &ac);
+		if (error) {
+			if (error == -EAGAIN)
+				return -ENOSPC;
+			return error;
+		}
+	}
+
+	/*
 	 * File data changes must be complete before we start the transaction to
 	 * modify the inode.  This needs to be done before joining the inode to
 	 * the transaction because the inode cannot be unlocked once it is a
@@ -888,11 +992,14 @@ xfs_setattr_size(
 	if (newsize > oldsize) {
 		trace_xfs_zero_eof(ip, oldsize, newsize - oldsize);
 		error = xfs_zero_range(ip, oldsize, newsize - oldsize,
-				&did_zeroing);
+				&ac, &did_zeroing);
 	} else {
-		error = xfs_truncate_page(ip, newsize, &did_zeroing);
+		error = xfs_truncate_page(ip, newsize, &ac, &did_zeroing);
 	}
 
+	if (xfs_is_zoned_inode(ip))
+		xfs_zoned_space_unreserve(ip, &ac);
+
 	if (error)
 		return error;