1 files changed, 778 insertions, 0 deletions

diff --git a/fs/xfs/libxfs/xfs_inode_fork.c b/fs/xfs/libxfs/xfs_inode_fork.c
new file mode 100644
index 000000000000..1772d82f2d68
--- /dev/null
+++ b/fs/xfs/libxfs/xfs_inode_fork.c
@@ -0,0 +1,778 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2000-2006 Silicon Graphics, Inc.
+ * All Rights Reserved.
+ */
+
+#include "xfs.h"
+#include "xfs_fs.h"
+#include "xfs_shared.h"
+#include "xfs_format.h"
+#include "xfs_log_format.h"
+#include "xfs_trans_resv.h"
+#include "xfs_mount.h"
+#include "xfs_inode.h"
+#include "xfs_trans.h"
+#include "xfs_inode_item.h"
+#include "xfs_btree.h"
+#include "xfs_bmap_btree.h"
+#include "xfs_bmap.h"
+#include "xfs_error.h"
+#include "xfs_trace.h"
+#include "xfs_da_format.h"
+#include "xfs_da_btree.h"
+#include "xfs_dir2_priv.h"
+#include "xfs_attr_leaf.h"
+#include "xfs_types.h"
+#include "xfs_errortag.h"
+#include "xfs_health.h"
+#include "xfs_symlink_remote.h"
+#include "xfs_rtrmap_btree.h"
+#include "xfs_rtrefcount_btree.h"
+
+struct kmem_cache *xfs_ifork_cache;
+
+void
+xfs_init_local_fork(
+	struct xfs_inode	*ip,
+	int			whichfork,
+	const void		*data,
+	int64_t			size)
+{
+	struct xfs_ifork	*ifp = xfs_ifork_ptr(ip, whichfork);
+	int			mem_size = size;
+	bool			zero_terminate;
+
+	/*
+	 * If we are using the local fork to store a symlink body we need to
+	 * zero-terminate it so that we can pass it back to the VFS directly.
+	 * Overallocate the in-memory fork by one for that and add a zero
+	 * to terminate it below.
+	 */
+	zero_terminate = S_ISLNK(VFS_I(ip)->i_mode);
+	if (zero_terminate)
+		mem_size++;
+
+	if (size) {
+		char *new_data = kmalloc(mem_size,
+				GFP_KERNEL | __GFP_NOLOCKDEP | __GFP_NOFAIL);
+
+		memcpy(new_data, data, size);
+		if (zero_terminate)
+			new_data[size] = '\0';
+
+		ifp->if_data = new_data;
+	} else {
+		ifp->if_data = NULL;
+	}
+
+	ifp->if_bytes = size;
+}
+
+/*
+ * The file is in-lined in the on-disk inode.
+ */
+STATIC int
+xfs_iformat_local(
+	struct xfs_inode	*ip,
+	struct xfs_dinode	*dip,
+	int			whichfork,
+	int			size)
+{
+	/*
+	 * If the size is unreasonable, then something
+	 * is wrong and we just bail out rather than crash in
+	 * kmalloc() or memcpy() below.
+	 */
+	if (unlikely(size > XFS_DFORK_SIZE(dip, ip->i_mount, whichfork))) {
+		xfs_warn(ip->i_mount,
+	"corrupt inode %llu (bad size %d for local fork, size = %zd).",
+			(unsigned long long) ip->i_ino, size,
+			XFS_DFORK_SIZE(dip, ip->i_mount, whichfork));
+		xfs_inode_verifier_error(ip, -EFSCORRUPTED,
+				"xfs_iformat_local", dip, sizeof(*dip),
+				__this_address);
+		xfs_inode_mark_sick(ip, XFS_SICK_INO_CORE);
+		return -EFSCORRUPTED;
+	}
+
+	xfs_init_local_fork(ip, whichfork, XFS_DFORK_PTR(dip, whichfork), size);
+	return 0;
+}
+
+/*
+ * The file consists of a set of extents all of which fit into the on-disk
+ * inode.
+ */
+STATIC int
+xfs_iformat_extents(
+	struct xfs_inode	*ip,
+	struct xfs_dinode	*dip,
+	int			whichfork)
+{
+	struct xfs_mount	*mp = ip->i_mount;
+	struct xfs_ifork	*ifp = xfs_ifork_ptr(ip, whichfork);
+	int			state = xfs_bmap_fork_to_state(whichfork);
+	xfs_extnum_t		nex = xfs_dfork_nextents(dip, whichfork);
+	int			size = nex * sizeof(xfs_bmbt_rec_t);
+	struct xfs_iext_cursor	icur;
+	struct xfs_bmbt_rec	*dp;
+	struct xfs_bmbt_irec	new;
+	int			i;
+
+	/*
+	 * If the number of extents is unreasonable, then something is wrong and
+	 * we just bail out rather than crash in kmalloc() or memcpy() below.
+	 */
+	if (unlikely(size < 0 || size > XFS_DFORK_SIZE(dip, mp, whichfork))) {
+		xfs_warn(ip->i_mount, "corrupt inode %llu ((a)extents = %llu).",
+			ip->i_ino, nex);
+		xfs_inode_verifier_error(ip, -EFSCORRUPTED,
+				"xfs_iformat_extents(1)", dip, sizeof(*dip),
+				__this_address);
+		xfs_inode_mark_sick(ip, XFS_SICK_INO_CORE);
+		return -EFSCORRUPTED;
+	}
+
+	ifp->if_bytes = 0;
+	ifp->if_data = NULL;
+	ifp->if_height = 0;
+	if (size) {
+		dp = (xfs_bmbt_rec_t *) XFS_DFORK_PTR(dip, whichfork);
+
+		xfs_iext_first(ifp, &icur);
+		for (i = 0; i < nex; i++, dp++) {
+			xfs_failaddr_t	fa;
+
+			xfs_bmbt_disk_get_all(dp, &new);
+			fa = xfs_bmap_validate_extent(ip, whichfork, &new);
+			if (fa) {
+				xfs_inode_verifier_error(ip, -EFSCORRUPTED,
+						"xfs_iformat_extents(2)",
+						dp, sizeof(*dp), fa);
+				xfs_inode_mark_sick(ip, XFS_SICK_INO_CORE);
+				return xfs_bmap_complain_bad_rec(ip, whichfork,
+						fa, &new);
+			}
+
+			xfs_iext_insert(ip, &icur, &new, state);
+			trace_xfs_read_extent(ip, &icur, state, _THIS_IP_);
+			xfs_iext_next(ifp, &icur);
+		}
+	}
+	return 0;
+}
+
+/*
+ * The file has too many extents to fit into
+ * the inode, so they are in B-tree format.
+ * Allocate a buffer for the root of the B-tree
+ * and copy the root into it.  The i_extents
+ * field will remain NULL until all of the
+ * extents are read in (when they are needed).
+ */
+STATIC int
+xfs_iformat_btree(
+	struct xfs_inode	*ip,
+	struct xfs_dinode	*dip,
+	int			whichfork)
+{
+	struct xfs_mount	*mp = ip->i_mount;
+	xfs_bmdr_block_t	*dfp;
+	struct xfs_ifork	*ifp;
+	struct xfs_btree_block	*broot;
+	int			nrecs;
+	int			size;
+	int			level;
+
+	ifp = xfs_ifork_ptr(ip, whichfork);
+	dfp = (xfs_bmdr_block_t *)XFS_DFORK_PTR(dip, whichfork);
+	size = xfs_bmap_broot_space(mp, dfp);
+	nrecs = be16_to_cpu(dfp->bb_numrecs);
+	level = be16_to_cpu(dfp->bb_level);
+
+	/*
+	 * blow out if -- fork has less extents than can fit in
+	 * fork (fork shouldn't be a btree format), root btree
+	 * block has more records than can fit into the fork,
+	 * or the number of extents is greater than the number of
+	 * blocks.
+	 */
+	if (unlikely(ifp->if_nextents <= XFS_IFORK_MAXEXT(ip, whichfork) ||
+		     nrecs == 0 ||
+		     xfs_bmdr_space_calc(nrecs) >
+					XFS_DFORK_SIZE(dip, mp, whichfork) ||
+		     ifp->if_nextents > ip->i_nblocks) ||
+		     level == 0 || level > XFS_BM_MAXLEVELS(mp, whichfork)) {
+		xfs_warn(mp, "corrupt inode %llu (btree).",
+					(unsigned long long) ip->i_ino);
+		xfs_inode_verifier_error(ip, -EFSCORRUPTED,
+				"xfs_iformat_btree", dfp, size,
+				__this_address);
+		xfs_inode_mark_sick(ip, XFS_SICK_INO_CORE);
+		return -EFSCORRUPTED;
+	}
+
+	broot = xfs_broot_alloc(ifp, size);
+	/*
+	 * Copy and convert from the on-disk structure
+	 * to the in-memory structure.
+	 */
+	xfs_bmdr_to_bmbt(ip, dfp, XFS_DFORK_SIZE(dip, ip->i_mount, whichfork),
+			 broot, size);
+
+	ifp->if_bytes = 0;
+	ifp->if_data = NULL;
+	ifp->if_height = 0;
+	return 0;
+}
+
+int
+xfs_iformat_data_fork(
+	struct xfs_inode	*ip,
+	struct xfs_dinode	*dip)
+{
+	struct inode		*inode = VFS_I(ip);
+	int			error;
+
+	/*
+	 * Initialize the extent count early, as the per-format routines may
+	 * depend on it.  Use release semantics to set needextents /after/ we
+	 * set the format. This ensures that we can use acquire semantics on
+	 * needextents in xfs_need_iread_extents() and be guaranteed to see a
+	 * valid format value after that load.
+	 */
+	ip->i_df.if_format = dip->di_format;
+	ip->i_df.if_nextents = xfs_dfork_data_extents(dip);
+	smp_store_release(&ip->i_df.if_needextents,
+			   ip->i_df.if_format == XFS_DINODE_FMT_BTREE ? 1 : 0);
+
+	switch (inode->i_mode & S_IFMT) {
+	case S_IFIFO:
+	case S_IFCHR:
+	case S_IFBLK:
+	case S_IFSOCK:
+		ip->i_disk_size = 0;
+		inode->i_rdev = xfs_to_linux_dev_t(xfs_dinode_get_rdev(dip));
+		return 0;
+	case S_IFREG:
+	case S_IFLNK:
+	case S_IFDIR:
+		switch (ip->i_df.if_format) {
+		case XFS_DINODE_FMT_LOCAL:
+			error = xfs_iformat_local(ip, dip, XFS_DATA_FORK,
+					be64_to_cpu(dip->di_size));
+			if (!error)
+				error = xfs_ifork_verify_local_data(ip);
+			return error;
+		case XFS_DINODE_FMT_EXTENTS:
+			return xfs_iformat_extents(ip, dip, XFS_DATA_FORK);
+		case XFS_DINODE_FMT_BTREE:
+			return xfs_iformat_btree(ip, dip, XFS_DATA_FORK);
+		case XFS_DINODE_FMT_META_BTREE:
+			switch (ip->i_metatype) {
+			case XFS_METAFILE_RTRMAP:
+				return xfs_iformat_rtrmap(ip, dip);
+			case XFS_METAFILE_RTREFCOUNT:
+				return xfs_iformat_rtrefcount(ip, dip);
+			default:
+				break;
+			}
+			fallthrough;
+		default:
+			xfs_inode_verifier_error(ip, -EFSCORRUPTED, __func__,
+					dip, sizeof(*dip), __this_address);
+			xfs_inode_mark_sick(ip, XFS_SICK_INO_CORE);
+			return -EFSCORRUPTED;
+		}
+		break;
+	default:
+		xfs_inode_verifier_error(ip, -EFSCORRUPTED, __func__, dip,
+				sizeof(*dip), __this_address);
+		xfs_inode_mark_sick(ip, XFS_SICK_INO_CORE);
+		return -EFSCORRUPTED;
+	}
+}
+
+static uint16_t
+xfs_dfork_attr_shortform_size(
+	struct xfs_dinode		*dip)
+{
+	struct xfs_attr_sf_hdr		*sf = XFS_DFORK_APTR(dip);
+
+	return be16_to_cpu(sf->totsize);
+}
+
+void
+xfs_ifork_init_attr(
+	struct xfs_inode	*ip,
+	enum xfs_dinode_fmt	format,
+	xfs_extnum_t		nextents)
+{
+	/*
+	 * Initialize the extent count early, as the per-format routines may
+	 * depend on it.  Use release semantics to set needextents /after/ we
+	 * set the format. This ensures that we can use acquire semantics on
+	 * needextents in xfs_need_iread_extents() and be guaranteed to see a
+	 * valid format value after that load.
+	 */
+	ip->i_af.if_format = format;
+	ip->i_af.if_nextents = nextents;
+	smp_store_release(&ip->i_af.if_needextents,
+			   ip->i_af.if_format == XFS_DINODE_FMT_BTREE ? 1 : 0);
+}
+
+void
+xfs_ifork_zap_attr(
+	struct xfs_inode	*ip)
+{
+	xfs_idestroy_fork(&ip->i_af);
+	memset(&ip->i_af, 0, sizeof(struct xfs_ifork));
+	ip->i_af.if_format = XFS_DINODE_FMT_EXTENTS;
+}
+
+int
+xfs_iformat_attr_fork(
+	struct xfs_inode	*ip,
+	struct xfs_dinode	*dip)
+{
+	xfs_extnum_t		naextents = xfs_dfork_attr_extents(dip);
+	int			error = 0;
+
+	/*
+	 * Initialize the extent count early, as the per-format routines may
+	 * depend on it.
+	 */
+	xfs_ifork_init_attr(ip, dip->di_aformat, naextents);
+
+	switch (ip->i_af.if_format) {
+	case XFS_DINODE_FMT_LOCAL:
+		error = xfs_iformat_local(ip, dip, XFS_ATTR_FORK,
+				xfs_dfork_attr_shortform_size(dip));
+		if (!error)
+			error = xfs_ifork_verify_local_attr(ip);
+		break;
+	case XFS_DINODE_FMT_EXTENTS:
+		error = xfs_iformat_extents(ip, dip, XFS_ATTR_FORK);
+		break;
+	case XFS_DINODE_FMT_BTREE:
+		error = xfs_iformat_btree(ip, dip, XFS_ATTR_FORK);
+		break;
+	default:
+		xfs_inode_verifier_error(ip, error, __func__, dip,
+				sizeof(*dip), __this_address);
+		xfs_inode_mark_sick(ip, XFS_SICK_INO_CORE);
+		error = -EFSCORRUPTED;
+		break;
+	}
+
+	if (error)
+		xfs_ifork_zap_attr(ip);
+	return error;
+}
+
+/*
+ * Allocate the if_broot component of an inode fork so that it is @new_size
+ * bytes in size, using __GFP_NOLOCKDEP like all the other code that
+ * initializes a broot during inode load.  Returns if_broot.
+ */
+struct xfs_btree_block *
+xfs_broot_alloc(
+	struct xfs_ifork	*ifp,
+	size_t			new_size)
+{
+	ASSERT(ifp->if_broot == NULL);
+
+	ifp->if_broot = kmalloc(new_size,
+				GFP_KERNEL | __GFP_NOLOCKDEP | __GFP_NOFAIL);
+	ifp->if_broot_bytes = new_size;
+	return ifp->if_broot;
+}
+
+/*
+ * Reallocate the if_broot component of an inode fork so that it is @new_size
+ * bytes in size.  Returns if_broot.
+ */
+struct xfs_btree_block *
+xfs_broot_realloc(
+	struct xfs_ifork	*ifp,
+	size_t			new_size)
+{
+	/* No size change?  No action needed. */
+	if (new_size == ifp->if_broot_bytes)
+		return ifp->if_broot;
+
+	/* New size is zero, free it. */
+	if (new_size == 0) {
+		ifp->if_broot_bytes = 0;
+		kfree(ifp->if_broot);
+		ifp->if_broot = NULL;
+		return NULL;
+	}
+
+	/*
+	 * Shrinking the iroot means we allocate a new smaller object and copy
+	 * it.  We don't trust krealloc not to nop on realloc-down.
+	 */
+	if (ifp->if_broot_bytes > 0 && ifp->if_broot_bytes > new_size) {
+		struct xfs_btree_block	*old_broot = ifp->if_broot;
+
+		ifp->if_broot = kmalloc(new_size, GFP_KERNEL | __GFP_NOFAIL);
+		ifp->if_broot_bytes = new_size;
+		memcpy(ifp->if_broot, old_broot, new_size);
+		kfree(old_broot);
+		return ifp->if_broot;
+	}
+
+	/*
+	 * Growing the iroot means we can krealloc.  This may get us the same
+	 * object.
+	 */
+	ifp->if_broot = krealloc(ifp->if_broot, new_size,
+			GFP_KERNEL | __GFP_NOFAIL);
+	ifp->if_broot_bytes = new_size;
+	return ifp->if_broot;
+}
+
+/*
+ * This is called when the amount of space needed for if_data
+ * is increased or decreased.  The change in size is indicated by
+ * the number of bytes that need to be added or deleted in the
+ * byte_diff parameter.
+ *
+ * If the amount of space needed has decreased below the size of the
+ * inline buffer, then switch to using the inline buffer.  Otherwise,
+ * use krealloc() or kmalloc() to adjust the size of the buffer
+ * to what is needed.
+ *
+ * ip -- the inode whose if_data area is changing
+ * byte_diff -- the change in the number of bytes, positive or negative,
+ *	 requested for the if_data array.
+ */
+void *
+xfs_idata_realloc(
+	struct xfs_inode	*ip,
+	int64_t			byte_diff,
+	int			whichfork)
+{
+	struct xfs_ifork	*ifp = xfs_ifork_ptr(ip, whichfork);
+	int64_t			new_size = ifp->if_bytes + byte_diff;
+
+	ASSERT(new_size >= 0);
+	ASSERT(new_size <= xfs_inode_fork_size(ip, whichfork));
+
+	if (byte_diff) {
+		ifp->if_data = krealloc(ifp->if_data, new_size,
+					GFP_KERNEL | __GFP_NOFAIL);
+		if (new_size == 0)
+			ifp->if_data = NULL;
+		ifp->if_bytes = new_size;
+	}
+
+	return ifp->if_data;
+}
+
+/* Free all memory and reset a fork back to its initial state. */
+void
+xfs_idestroy_fork(
+	struct xfs_ifork	*ifp)
+{
+	if (ifp->if_broot != NULL) {
+		kfree(ifp->if_broot);
+		ifp->if_broot = NULL;
+	}
+
+	switch (ifp->if_format) {
+	case XFS_DINODE_FMT_LOCAL:
+		kfree(ifp->if_data);
+		ifp->if_data = NULL;
+		break;
+	case XFS_DINODE_FMT_EXTENTS:
+	case XFS_DINODE_FMT_BTREE:
+		if (ifp->if_height)
+			xfs_iext_destroy(ifp);
+		break;
+	}
+}
+
+/*
+ * Convert in-core extents to on-disk form
+ *
+ * In the case of the data fork, the in-core and on-disk fork sizes can be
+ * different due to delayed allocation extents. We only copy on-disk extents
+ * here, so callers must always use the physical fork size to determine the
+ * size of the buffer passed to this routine.  We will return the size actually
+ * used.
+ */
+int
+xfs_iextents_copy(
+	struct xfs_inode	*ip,
+	struct xfs_bmbt_rec	*dp,
+	int			whichfork)
+{
+	int			state = xfs_bmap_fork_to_state(whichfork);
+	struct xfs_ifork	*ifp = xfs_ifork_ptr(ip, whichfork);
+	struct xfs_iext_cursor	icur;
+	struct xfs_bmbt_irec	rec;
+	int64_t			copied = 0;
+
+	xfs_assert_ilocked(ip, XFS_ILOCK_EXCL | XFS_ILOCK_SHARED);
+	ASSERT(ifp->if_bytes > 0);
+
+	for_each_xfs_iext(ifp, &icur, &rec) {
+		if (isnullstartblock(rec.br_startblock))
+			continue;
+		ASSERT(xfs_bmap_validate_extent(ip, whichfork, &rec) == NULL);
+		xfs_bmbt_disk_set_all(dp, &rec);
+		trace_xfs_write_extent(ip, &icur, state, _RET_IP_);
+		copied += sizeof(struct xfs_bmbt_rec);
+		dp++;
+	}
+
+	ASSERT(copied > 0);
+	ASSERT(copied <= ifp->if_bytes);
+	return copied;
+}
+
+/*
+ * Each of the following cases stores data into the same region
+ * of the on-disk inode, so only one of them can be valid at
+ * any given time. While it is possible to have conflicting formats
+ * and log flags, e.g. having XFS_ILOG_?DATA set when the fork is
+ * in EXTENTS format, this can only happen when the fork has
+ * changed formats after being modified but before being flushed.
+ * In these cases, the format always takes precedence, because the
+ * format indicates the current state of the fork.
+ */
+void
+xfs_iflush_fork(
+	struct xfs_inode	*ip,
+	struct xfs_dinode	*dip,
+	struct xfs_inode_log_item *iip,
+	int			whichfork)
+{
+	char			*cp;
+	struct xfs_ifork	*ifp;
+	xfs_mount_t		*mp;
+	static const short	brootflag[2] =
+		{ XFS_ILOG_DBROOT, XFS_ILOG_ABROOT };
+	static const short	dataflag[2] =
+		{ XFS_ILOG_DDATA, XFS_ILOG_ADATA };
+	static const short	extflag[2] =
+		{ XFS_ILOG_DEXT, XFS_ILOG_AEXT };
+
+	if (!iip)
+		return;
+	ifp = xfs_ifork_ptr(ip, whichfork);
+	/*
+	 * This can happen if we gave up in iformat in an error path,
+	 * for the attribute fork.
+	 */
+	if (!ifp) {
+		ASSERT(whichfork == XFS_ATTR_FORK);
+		return;
+	}
+	cp = XFS_DFORK_PTR(dip, whichfork);
+	mp = ip->i_mount;
+	switch (ifp->if_format) {
+	case XFS_DINODE_FMT_LOCAL:
+		if ((iip->ili_fields & dataflag[whichfork]) &&
+		    (ifp->if_bytes > 0)) {
+			ASSERT(ifp->if_data != NULL);
+			ASSERT(ifp->if_bytes <= xfs_inode_fork_size(ip, whichfork));
+			memcpy(cp, ifp->if_data, ifp->if_bytes);
+		}
+		break;
+
+	case XFS_DINODE_FMT_EXTENTS:
+		if ((iip->ili_fields & extflag[whichfork]) &&
+		    (ifp->if_bytes > 0)) {
+			ASSERT(ifp->if_nextents > 0);
+			(void)xfs_iextents_copy(ip, (xfs_bmbt_rec_t *)cp,
+				whichfork);
+		}
+		break;
+
+	case XFS_DINODE_FMT_BTREE:
+		if ((iip->ili_fields & brootflag[whichfork]) &&
+		    (ifp->if_broot_bytes > 0)) {
+			ASSERT(ifp->if_broot != NULL);
+			ASSERT(xfs_bmap_bmdr_space(ifp->if_broot) <=
+			        xfs_inode_fork_size(ip, whichfork));
+			xfs_bmbt_to_bmdr(mp, ifp->if_broot, ifp->if_broot_bytes,
+				(xfs_bmdr_block_t *)cp,
+				XFS_DFORK_SIZE(dip, mp, whichfork));
+		}
+		break;
+
+	case XFS_DINODE_FMT_DEV:
+		if (iip->ili_fields & XFS_ILOG_DEV) {
+			ASSERT(whichfork == XFS_DATA_FORK);
+			xfs_dinode_put_rdev(dip,
+					linux_to_xfs_dev_t(VFS_I(ip)->i_rdev));
+		}
+		break;
+
+	case XFS_DINODE_FMT_META_BTREE:
+		ASSERT(whichfork == XFS_DATA_FORK);
+
+		if (!(iip->ili_fields & brootflag[whichfork]))
+			break;
+
+		switch (ip->i_metatype) {
+		case XFS_METAFILE_RTRMAP:
+			xfs_iflush_rtrmap(ip, dip);
+			break;
+		case XFS_METAFILE_RTREFCOUNT:
+			xfs_iflush_rtrefcount(ip, dip);
+			break;
+		default:
+			ASSERT(0);
+			break;
+		}
+		break;
+
+	default:
+		ASSERT(0);
+		break;
+	}
+}
+
+/* Convert bmap state flags to an inode fork. */
+struct xfs_ifork *
+xfs_iext_state_to_fork(
+	struct xfs_inode	*ip,
+	int			state)
+{
+	if (state & BMAP_COWFORK)
+		return ip->i_cowfp;
+	else if (state & BMAP_ATTRFORK)
+		return &ip->i_af;
+	return &ip->i_df;
+}
+
+/*
+ * Initialize an inode's copy-on-write fork.
+ */
+void
+xfs_ifork_init_cow(
+	struct xfs_inode	*ip)
+{
+	if (ip->i_cowfp)
+		return;
+
+	ip->i_cowfp = kmem_cache_zalloc(xfs_ifork_cache,
+				GFP_KERNEL | __GFP_NOLOCKDEP | __GFP_NOFAIL);
+	ip->i_cowfp->if_format = XFS_DINODE_FMT_EXTENTS;
+}
+
+/* Verify the inline contents of the data fork of an inode. */
+int
+xfs_ifork_verify_local_data(
+	struct xfs_inode	*ip)
+{
+	xfs_failaddr_t		fa = NULL;
+
+	switch (VFS_I(ip)->i_mode & S_IFMT) {
+	case S_IFDIR: {
+		struct xfs_mount	*mp = ip->i_mount;
+		struct xfs_ifork	*ifp = xfs_ifork_ptr(ip, XFS_DATA_FORK);
+		struct xfs_dir2_sf_hdr	*sfp = ifp->if_data;
+
+		fa = xfs_dir2_sf_verify(mp, sfp, ifp->if_bytes);
+		break;
+	}
+	case S_IFLNK: {
+		struct xfs_ifork	*ifp = xfs_ifork_ptr(ip, XFS_DATA_FORK);
+
+		fa = xfs_symlink_shortform_verify(ifp->if_data, ifp->if_bytes);
+		break;
+	}
+	default:
+		break;
+	}
+
+	if (fa) {
+		xfs_inode_verifier_error(ip, -EFSCORRUPTED, "data fork",
+				ip->i_df.if_data, ip->i_df.if_bytes, fa);
+		return -EFSCORRUPTED;
+	}
+
+	return 0;
+}
+
+/* Verify the inline contents of the attr fork of an inode. */
+int
+xfs_ifork_verify_local_attr(
+	struct xfs_inode	*ip)
+{
+	struct xfs_ifork	*ifp = &ip->i_af;
+	xfs_failaddr_t		fa;
+
+	if (!xfs_inode_has_attr_fork(ip)) {
+		fa = __this_address;
+	} else {
+		struct xfs_ifork		*ifp = &ip->i_af;
+
+		ASSERT(ifp->if_format == XFS_DINODE_FMT_LOCAL);
+		fa = xfs_attr_shortform_verify(ifp->if_data, ifp->if_bytes);
+	}
+	if (fa) {
+		xfs_inode_verifier_error(ip, -EFSCORRUPTED, "attr fork",
+				ifp->if_data, ifp->if_bytes, fa);
+		return -EFSCORRUPTED;
+	}
+
+	return 0;
+}
+
+/*
+ * Check if the inode fork supports adding nr_to_add more extents.
+ *
+ * If it doesn't but we can upgrade it to large extent counters, do the upgrade.
+ * If we can't upgrade or are already using big counters but still can't fit the
+ * additional extents, return -EFBIG.
+ */
+int
+xfs_iext_count_extend(
+	struct xfs_trans	*tp,
+	struct xfs_inode	*ip,
+	int			whichfork,
+	uint			nr_to_add)
+{
+	struct xfs_mount	*mp = ip->i_mount;
+	bool			has_large =
+		xfs_inode_has_large_extent_counts(ip);
+	struct xfs_ifork	*ifp = xfs_ifork_ptr(ip, whichfork);
+	uint64_t		nr_exts;
+
+	ASSERT(nr_to_add <= XFS_MAX_EXTCNT_UPGRADE_NR);
+
+	if (whichfork == XFS_COW_FORK)
+		return 0;
+
+	/* no point in upgrading if if_nextents overflows */
+	nr_exts = ifp->if_nextents + nr_to_add;
+	if (nr_exts < ifp->if_nextents)
+		return -EFBIG;
+
+	if (XFS_TEST_ERROR(mp, XFS_ERRTAG_REDUCE_MAX_IEXTENTS) && nr_exts > 10)
+		return -EFBIG;
+
+	if (nr_exts > xfs_iext_max_nextents(has_large, whichfork)) {
+		if (has_large || !xfs_has_large_extent_counts(mp))
+			return -EFBIG;
+		ip->i_diflags2 |= XFS_DIFLAG2_NREXT64;
+		xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
+	}
+	return 0;
+}
+
+/* Decide if a file mapping is on the realtime device or not. */
+bool
+xfs_ifork_is_realtime(
+	struct xfs_inode	*ip,
+	int			whichfork)
+{
+	return XFS_IS_REALTIME_INODE(ip) && whichfork != XFS_ATTR_FORK;
+}