Merge tag 'scrub-cleanup-malloc-6.2_2022-11-16' of git://git.kernel.org/pub/scm/linux/kernel/git/djwong/xfs-linux into xfs-6.2-mergeA

xfs: clean up memory allocations in online fsck

This series standardizes the GFP_ flags that we use for memory
allocation in online scrub, and convert the callers away from the old
kmem_alloc code that was ported from Irix.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>

* tag 'scrub-cleanup-malloc-6.2_2022-11-16' of git://git.kernel.org/pub/scm/linux/kernel/git/djwong/xfs-linux:
  xfs: pivot online scrub away from kmem.[ch]
  xfs: initialize the check_owner object fully
  xfs: standardize GFP flags usage in online scrub

fs/xfs/scrub/agheader.c

@@ -737,7 +737,7 @@ xchk_agfl(
 		goto out;
 	}
 	sai.entries = kvcalloc(sai.agflcount, sizeof(xfs_agblock_t),
-			GFP_KERNEL | __GFP_RETRY_MAYFAIL);
+			       XCHK_GFP_FLAGS);
 	if (!sai.entries) {
 		error = -ENOMEM;
 		goto out;

fs/xfs/scrub/agheader_repair.c

@@ -685,7 +685,7 @@ xrep_agfl_init_header(
 		if (br->len)
 			break;
 		list_del(&br->list);
-		kmem_free(br);
+		kfree(br);
 	}
 
 	/* Write new AGFL to disk. */

fs/xfs/scrub/attr.c

@@ -49,7 +49,7 @@ xchk_setup_xattr_buf(
 	if (ab) {
 		if (sz <= ab->sz)
 			return 0;
-		kmem_free(ab);
+		kvfree(ab);
 		sc->buf = NULL;
 	}
 
@@ -79,7 +79,8 @@ xchk_setup_xattr(
 	 * without the inode lock held, which means we can sleep.
 	 */
 	if (sc->flags & XCHK_TRY_HARDER) {
-		error = xchk_setup_xattr_buf(sc, XATTR_SIZE_MAX, GFP_KERNEL);
+		error = xchk_setup_xattr_buf(sc, XATTR_SIZE_MAX,
+				XCHK_GFP_FLAGS);
 		if (error)
 			return error;
 	}
@@ -138,8 +139,7 @@ xchk_xattr_listent(
 	 * doesn't work, we overload the seen_enough variable to convey
 	 * the error message back to the main scrub function.
 	 */
-	error = xchk_setup_xattr_buf(sx->sc, valuelen,
-			GFP_KERNEL | __GFP_RETRY_MAYFAIL);
+	error = xchk_setup_xattr_buf(sx->sc, valuelen, XCHK_GFP_FLAGS);
 	if (error == -ENOMEM)
 		error = -EDEADLOCK;
 	if (error) {
@@ -324,8 +324,7 @@ xchk_xattr_block(
 		return 0;
 
 	/* Allocate memory for block usage checking. */
-	error = xchk_setup_xattr_buf(ds->sc, 0,
-			GFP_KERNEL | __GFP_RETRY_MAYFAIL);
+	error = xchk_setup_xattr_buf(ds->sc, 0, XCHK_GFP_FLAGS);
 	if (error == -ENOMEM)
 		return -EDEADLOCK;
 	if (error)

fs/xfs/scrub/bitmap.c

@@ -10,6 +10,7 @@
 #include "xfs_trans_resv.h"
 #include "xfs_mount.h"
 #include "xfs_btree.h"
+#include "scrub/scrub.h"
 #include "scrub/bitmap.h"
 
 /*
@@ -25,7 +26,7 @@ xbitmap_set(
 {
 	struct xbitmap_range	*bmr;
 
-	bmr = kmem_alloc(sizeof(struct xbitmap_range), KM_MAYFAIL);
+	bmr = kmalloc(sizeof(struct xbitmap_range), XCHK_GFP_FLAGS);
 	if (!bmr)
 		return -ENOMEM;
 
@@ -47,7 +48,7 @@ xbitmap_destroy(
 
 	for_each_xbitmap_extent(bmr, n, bitmap) {
 		list_del(&bmr->list);
-		kmem_free(bmr);
+		kfree(bmr);
 	}
 }
 
@@ -174,15 +175,15 @@ xbitmap_disunion(
 			/* Total overlap, just delete ex. */
 			lp = lp->next;
 			list_del(&br->list);
-			kmem_free(br);
+			kfree(br);
 			break;
 		case 0:
 			/*
 			 * Deleting from the middle: add the new right extent
 			 * and then shrink the left extent.
 			 */
-			new_br = kmem_alloc(sizeof(struct xbitmap_range),
-					KM_MAYFAIL);
+			new_br = kmalloc(sizeof(struct xbitmap_range),
+					XCHK_GFP_FLAGS);
 			if (!new_br) {
 				error = -ENOMEM;
 				goto out;

fs/xfs/scrub/btree.c

@@ -408,7 +408,6 @@ xchk_btree_check_owner(
 	struct xfs_buf		*bp)
 {
 	struct xfs_btree_cur	*cur = bs->cur;
-	struct check_owner	*co;
 
 	/*
 	 * In theory, xfs_btree_get_block should only give us a null buffer
@@ -431,10 +430,13 @@ xchk_btree_check_owner(
 	 * later scanning.
 	 */
 	if (cur->bc_btnum == XFS_BTNUM_BNO || cur->bc_btnum == XFS_BTNUM_RMAP) {
-		co = kmem_alloc(sizeof(struct check_owner),
-				KM_MAYFAIL);
+		struct check_owner	*co;
+
+		co = kmalloc(sizeof(struct check_owner), XCHK_GFP_FLAGS);
 		if (!co)
 			return -ENOMEM;
+
+		INIT_LIST_HEAD(&co->list);
 		co->level = level;
 		co->daddr = xfs_buf_daddr(bp);
 		list_add_tail(&co->list, &bs->to_check);
@@ -649,7 +651,7 @@ xchk_btree(
 		xchk_btree_set_corrupt(sc, cur, 0);
 		return 0;
 	}
-	bs = kmem_zalloc(cur_sz, KM_NOFS | KM_MAYFAIL);
+	bs = kzalloc(cur_sz, XCHK_GFP_FLAGS);
 	if (!bs)
 		return -ENOMEM;
 	bs->cur = cur;
@@ -740,9 +742,9 @@ xchk_btree(
 			error = xchk_btree_check_block_owner(bs, co->level,
 					co->daddr);
 		list_del(&co->list);
-		kmem_free(co);
+		kfree(co);
 	}
-	kmem_free(bs);
+	kfree(bs);
 
 	return error;
 }

fs/xfs/scrub/dabtree.c

@@ -486,7 +486,7 @@ xchk_da_btree(
 		return 0;
 
 	/* Set up initial da state. */
-	ds = kmem_zalloc(sizeof(struct xchk_da_btree), KM_NOFS | KM_MAYFAIL);
+	ds = kzalloc(sizeof(struct xchk_da_btree), XCHK_GFP_FLAGS);
 	if (!ds)
 		return -ENOMEM;
 	ds->dargs.dp = sc->ip;
@@ -591,6 +591,6 @@ xchk_da_btree(
 
 out_state:
 	xfs_da_state_free(ds->state);
-	kmem_free(ds);
+	kfree(ds);
 	return error;
 }

fs/xfs/scrub/fscounters.c

@@ -116,7 +116,7 @@ xchk_setup_fscounters(
 	struct xchk_fscounters	*fsc;
 	int			error;
 
-	sc->buf = kmem_zalloc(sizeof(struct xchk_fscounters), 0);
+	sc->buf = kzalloc(sizeof(struct xchk_fscounters), XCHK_GFP_FLAGS);
 	if (!sc->buf)
 		return -ENOMEM;
 	fsc = sc->buf;

fs/xfs/scrub/refcount.c

@@ -127,8 +127,8 @@ xchk_refcountbt_rmap_check(
 		 * is healthy each rmap_irec we see will be in agbno order
 		 * so we don't need insertion sort here.
 		 */
-		frag = kmem_alloc(sizeof(struct xchk_refcnt_frag),
-				KM_MAYFAIL);
+		frag = kmalloc(sizeof(struct xchk_refcnt_frag),
+				XCHK_GFP_FLAGS);
 		if (!frag)
 			return -ENOMEM;
 		memcpy(&frag->rm, rec, sizeof(frag->rm));
@@ -215,7 +215,7 @@ xchk_refcountbt_process_rmap_fragments(
 				continue;
 			}
 			list_del(&frag->list);
-			kmem_free(frag);
+			kfree(frag);
 			nr++;
 		}
 
@@ -257,11 +257,11 @@ xchk_refcountbt_process_rmap_fragments(
 	/* Delete fragments and work list. */
 	list_for_each_entry_safe(frag, n, &worklist, list) {
 		list_del(&frag->list);
-		kmem_free(frag);
+		kfree(frag);
 	}
 	list_for_each_entry_safe(frag, n, &refchk->fragments, list) {
 		list_del(&frag->list);
-		kmem_free(frag);
+		kfree(frag);
 	}
 }
 
@@ -306,7 +306,7 @@ xchk_refcountbt_xref_rmap(
 out_free:
 	list_for_each_entry_safe(frag, n, &refchk.fragments, list) {
 		list_del(&frag->list);
-		kmem_free(frag);
+		kfree(frag);
 	}
 }
 

fs/xfs/scrub/scrub.c

@@ -174,7 +174,7 @@ xchk_teardown(
 	if (sc->flags & XCHK_REAPING_DISABLED)
 		xchk_start_reaping(sc);
 	if (sc->buf) {
-		kmem_free(sc->buf);
+		kvfree(sc->buf);
 		sc->buf = NULL;
 	}
 	return error;
@@ -467,7 +467,7 @@ xfs_scrub_metadata(
 	xfs_warn_mount(mp, XFS_OPSTATE_WARNED_SCRUB,
  "EXPERIMENTAL online scrub feature in use. Use at your own risk!");
 
-	sc = kmem_zalloc(sizeof(struct xfs_scrub), KM_NOFS | KM_MAYFAIL);
+	sc = kzalloc(sizeof(struct xfs_scrub), XCHK_GFP_FLAGS);
 	if (!sc) {
 		error = -ENOMEM;
 		goto out;
@@ -557,7 +557,7 @@ xfs_scrub_metadata(
 out_teardown:
 	error = xchk_teardown(sc, error);
 out_sc:
-	kmem_free(sc);
+	kfree(sc);
 out:
 	trace_xchk_done(XFS_I(file_inode(file)), sm, error);
 	if (error == -EFSCORRUPTED || error == -EFSBADCRC) {

fs/xfs/scrub/scrub.h

@@ -8,6 +8,15 @@
 
 struct xfs_scrub;
 
+/*
+ * Standard flags for allocating memory within scrub.  NOFS context is
+ * configured by the process allocation scope.  Scrub and repair must be able
+ * to back out gracefully if there isn't enough memory.  Force-cast to avoid
+ * complaints from static checkers.
+ */
+#define XCHK_GFP_FLAGS	((__force gfp_t)(GFP_KERNEL | __GFP_NOWARN | \
+					 __GFP_RETRY_MAYFAIL))
+
 /* Type info and names for the scrub types. */
 enum xchk_type {
 	ST_NONE = 1,	/* disabled */

fs/xfs/scrub/symlink.c

@@ -21,7 +21,7 @@ xchk_setup_symlink(
 	struct xfs_scrub	*sc)
 {
 	/* Allocate the buffer without the inode lock held. */
-	sc->buf = kvzalloc(XFS_SYMLINK_MAXLEN + 1, GFP_KERNEL);
+	sc->buf = kvzalloc(XFS_SYMLINK_MAXLEN + 1, XCHK_GFP_FLAGS);
 	if (!sc->buf)
 		return -ENOMEM;