Merge tag 'xfs-6.4-merge-1' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux

Pull xfs updates from Dave Chinner:
 "This consists mainly of online scrub functionality and the design
  documentation for the upcoming online repair functionality built on
  top of the scrub code:

   - Added detailed design documentation for the upcoming online repair
     feature

   - major update to online scrub to complete the reverse mapping
     cross-referencing infrastructure enabling us to fully validate
     allocated metadata against owner records. This is the last piece of
     scrub infrastructure needed before we can start merging online
     repair functionality.

   - Fixes for the ascii-ci hashing issues

   - deprecation of the ascii-ci functionality

   - on-disk format verification bug fixes

   - various random bug fixes for syzbot and other bug reports"

* tag 'xfs-6.4-merge-1' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux: (107 commits)
  xfs: fix livelock in delayed allocation at ENOSPC
  xfs: Extend table marker on deprecated mount options table
  xfs: fix duplicate includes
  xfs: fix BUG_ON in xfs_getbmap()
  xfs: verify buffer contents when we skip log replay
  xfs: _{attr,data}_map_shared should take ILOCK_EXCL until iread_extents is completely done
  xfs: remove WARN when dquot cache insertion fails
  xfs: don't consider future format versions valid
  xfs: deprecate the ascii-ci feature
  xfs: test the ascii case-insensitive hash
  xfs: stabilize the dirent name transformation function used for ascii-ci dir hash computation
  xfs: cross-reference rmap records with refcount btrees
  xfs: cross-reference rmap records with inode btrees
  xfs: cross-reference rmap records with free space btrees
  xfs: cross-reference rmap records with ag btrees
  xfs: introduce bitmap type for AG blocks
  xfs: convert xbitmap to interval tree
  xfs: drop the _safe behavior from the xbitmap foreach macro
  xfs: don't load local xattr values during scrub
  xfs: remove the for_each_xbitmap_ helpers
  ...

Author: torvalds

Documentation/admin-guide/xfs.rst

@@ -236,13 +236,14 @@ the dates listed above.
 Deprecated Mount Options
 ========================
 
-===========================     ================
+============================    ================
   Name				Removal Schedule
-===========================     ================
+============================    ================
 Mounting with V4 filesystem     September 2030
+Mounting ascii-ci filesystem    September 2030
 ikeep/noikeep			September 2025
 attr2/noattr2			September 2025
-===========================     ================
+============================    ================
 
 
 Removed Mount Options

Documentation/filesystems/index.rst

@@ -123,4 +123,5 @@ Documentation for filesystem implementations.
    vfat
    xfs-delayed-logging-design
    xfs-self-describing-metadata
+   xfs-online-fsck-design
    zonefs

Documentation/filesystems/xfs-online-fsck-design.rst

@@ -1,4 +1,5 @@
 .. SPDX-License-Identifier: GPL-2.0
+.. _xfs_self_describing_metadata:
 
 ============================
 XFS Self Describing Metadata

Documentation/filesystems/xfs-self-describing-metadata.rst

@@ -47,6 +47,33 @@ config XFS_SUPPORT_V4
 	  To continue supporting the old V4 format (crc=0), say Y.
 	  To close off an attack surface, say N.
 
+config XFS_SUPPORT_ASCII_CI
+	bool "Support deprecated case-insensitive ascii (ascii-ci=1) format"
+	depends on XFS_FS
+	default y
+	help
+	  The ASCII case insensitivity filesystem feature only works correctly
+	  on systems that have been coerced into using ISO 8859-1, and it does
+	  not work on extended attributes.  The kernel has no visibility into
+	  the locale settings in userspace, so it corrupts UTF-8 names.
+	  Enabling this feature makes XFS vulnerable to mixed case sensitivity
+	  attacks.  Because of this, the feature is deprecated.  All users
+	  should upgrade by backing up their files, reformatting, and restoring
+	  from the backup.
+
+	  Administrators and users can detect such a filesystem by running
+	  xfs_info against a filesystem mountpoint and checking for a string
+	  beginning with "ascii-ci=".  If the string "ascii-ci=1" is found, the
+	  filesystem is a case-insensitive filesystem.  If no such string is
+	  found, please upgrade xfsprogs to the latest version and try again.
+
+	  This option will become default N in September 2025.  Support for the
+	  feature will be removed entirely in September 2030.  Distributors
+	  can say N here to withdraw support earlier.
+
+	  To continue supporting case-insensitivity (ascii-ci=1), say Y.
+	  To close off an attack surface, say N.
+
 config XFS_QUOTA
 	bool "XFS Quota support"
 	depends on XFS_FS
@@ -93,10 +120,15 @@ config XFS_RT
 
 	  If unsure, say N.
 
+config XFS_DRAIN_INTENTS
+	bool
+	select JUMP_LABEL if HAVE_ARCH_JUMP_LABEL
+
 config XFS_ONLINE_SCRUB
 	bool "XFS online metadata check support"
 	default n
 	depends on XFS_FS
+	select XFS_DRAIN_INTENTS
 	help
 	  If you say Y here you will be able to check metadata on a
 	  mounted XFS filesystem.  This feature is intended to reduce

fs/xfs/Kconfig

@@ -136,6 +136,8 @@ ifeq ($(CONFIG_MEMORY_FAILURE),y)
 xfs-$(CONFIG_FS_DAX)		+= xfs_notify_failure.o
 endif
 
+xfs-$(CONFIG_XFS_DRAIN_INTENTS)	+= xfs_drain.o
+
 # online scrub/repair
 ifeq ($(CONFIG_XFS_ONLINE_SCRUB),y)
 
@@ -146,6 +148,7 @@ xfs-y				+= $(addprefix scrub/, \
 				   agheader.o \
 				   alloc.o \
 				   attr.o \
+				   bitmap.o \
 				   bmap.o \
 				   btree.o \
 				   common.o \
@@ -156,6 +159,7 @@ xfs-y				+= $(addprefix scrub/, \
 				   ialloc.o \
 				   inode.o \
 				   parent.o \
+				   readdir.o \
 				   refcount.o \
 				   rmap.o \
 				   scrub.o \
@@ -169,7 +173,6 @@ xfs-$(CONFIG_XFS_QUOTA)		+= scrub/quota.o
 ifeq ($(CONFIG_XFS_ONLINE_REPAIR),y)
 xfs-y				+= $(addprefix scrub/, \
 				   agheader_repair.o \
-				   bitmap.o \
 				   repair.o \
 				   )
 endif

fs/xfs/Makefile

@@ -81,6 +81,19 @@ xfs_perag_get_tag(
 	return pag;
 }
 
+/* Get a passive reference to the given perag. */
+struct xfs_perag *
+xfs_perag_hold(
+	struct xfs_perag	*pag)
+{
+	ASSERT(atomic_read(&pag->pag_ref) > 0 ||
+	       atomic_read(&pag->pag_active_ref) > 0);
+
+	trace_xfs_perag_hold(pag, _RET_IP_);
+	atomic_inc(&pag->pag_ref);
+	return pag;
+}
+
 void
 xfs_perag_put(
 	struct xfs_perag	*pag)
@@ -247,6 +260,7 @@ xfs_free_perag(
 		spin_unlock(&mp->m_perag_lock);
 		ASSERT(pag);
 		XFS_IS_CORRUPT(pag->pag_mount, atomic_read(&pag->pag_ref) != 0);
+		xfs_defer_drain_free(&pag->pag_intents_drain);
 
 		cancel_delayed_work_sync(&pag->pag_blockgc_work);
 		xfs_buf_hash_destroy(pag);
@@ -372,6 +386,7 @@ xfs_initialize_perag(
 		spin_lock_init(&pag->pag_state_lock);
 		INIT_DELAYED_WORK(&pag->pag_blockgc_work, xfs_blockgc_worker);
 		INIT_RADIX_TREE(&pag->pag_ici_root, GFP_ATOMIC);
+		xfs_defer_drain_init(&pag->pag_intents_drain);
 		init_waitqueue_head(&pag->pagb_wait);
 		init_waitqueue_head(&pag->pag_active_wq);
 		pag->pagb_count = 0;
@@ -408,6 +423,7 @@ xfs_initialize_perag(
 	return 0;
 
 out_remove_pag:
+	xfs_defer_drain_free(&pag->pag_intents_drain);
 	radix_tree_delete(&mp->m_perag_tree, index);
 out_free_pag:
 	kmem_free(pag);
@@ -418,6 +434,7 @@ xfs_initialize_perag(
 		if (!pag)
 			break;
 		xfs_buf_hash_destroy(pag);
+		xfs_defer_drain_free(&pag->pag_intents_drain);
 		kmem_free(pag);
 	}
 	return error;
@@ -1043,10 +1060,8 @@ xfs_ag_extend_space(
 	if (error)
 		return error;
 
-	error = xfs_free_extent(tp, XFS_AGB_TO_FSB(pag->pag_mount, pag->pag_agno,
-					be32_to_cpu(agf->agf_length) - len),
-				len, &XFS_RMAP_OINFO_SKIP_UPDATE,
-				XFS_AG_RESV_NONE);
+	error = xfs_free_extent(tp, pag, be32_to_cpu(agf->agf_length) - len,
+			len, &XFS_RMAP_OINFO_SKIP_UPDATE, XFS_AG_RESV_NONE);
 	if (error)
 		return error;
 

fs/xfs/libxfs/xfs_ag.c

@@ -101,6 +101,14 @@ struct xfs_perag {
 	/* background prealloc block trimming */
 	struct delayed_work	pag_blockgc_work;
 
+	/*
+	 * We use xfs_drain to track the number of deferred log intent items
+	 * that have been queued (but not yet processed) so that waiters (e.g.
+	 * scrub) will not lock resources when other threads are in the middle
+	 * of processing a chain of intent items only to find momentary
+	 * inconsistencies.
+	 */
+	struct xfs_defer_drain	pag_intents_drain;
 #endif /* __KERNEL__ */
 };
 
@@ -134,6 +142,7 @@ void xfs_free_perag(struct xfs_mount *mp);
 struct xfs_perag *xfs_perag_get(struct xfs_mount *mp, xfs_agnumber_t agno);
 struct xfs_perag *xfs_perag_get_tag(struct xfs_mount *mp, xfs_agnumber_t agno,
 		unsigned int tag);
+struct xfs_perag *xfs_perag_hold(struct xfs_perag *pag);
 void xfs_perag_put(struct xfs_perag *pag);
 
 /* Active AG references */