Merge tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linuxgrafted

Pull I3C updates from Alexandre Belloni:
 "A new driver this cycle, for the AMD AXI I3C controller.

  There are also new features such as IBI wakeup support, SETAASA device
  discovery and ACPI support for the the DAA methods, meaning we can now
  communicate with the SPD devices on DDR5 modules.

  New driver:
   - AMD AXI I3C master controller

  Subsystem:
   - I3C Common Command Code (CCC) handling improvements, especially
     around GET CCCs
   - SETAASA device discovery support
   - ACPI support for all existing DAA methods like SETDASA, SETNEWDA as
     well as I2C devices on I3C bus
   - IBI-based wakeup support

  Drivers:
   - dw: SETAASA support
   - mipi-i3c-hci: advertise IBI wakeup capability, AMD_PT I3C
     controller support, PIO queue management support for HCI v1.2
   - renesas: improve suspend to RAM support, add runtime PM support"

* tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux: (70 commits)
  i3c: dw: reduce do_daa time if there's no client
  i3c: mipi-i3c-hci: Add support for AMD_PT I3C controller
  i3c: mipi-i3c-hci: Add PIO queue management support for HCI v1.2
  i3c: mipi-i3c-hci: Fix missing STAT_IBI_STATUS_THLD in PIO mode
  i3c: dw: rename "pclk" to "apb" to match dt-binding
  i3c: dw: make struct dw_i3c_cmd smaller
  i3c: dw: use COMMAND_PORT_TRANSFER_ARG instead of hardcoding
  i3c: renesas: Don't register devices when ENTDAA times out
  i3c: master: dw-i3c-master: fix OD timing for first broadcast
  i3c: mipi-i3c-hci: Advertise IBI wakeup capability
  i3c: mipi-i3c-hci: Factor out i3c_hci_sysdev()
  i3c: mipi-i3c-hci-pci: Propagate I3C wakeup requirements to PCI
  i3c: master: Reject IBI requests from non-IBI-capable devices
  i3c: master: Add helper to query bus wakeup requirements
  i3c: master: Report wakeup events for IBIs
  i3c: master: Support IBI-based wakeup capability
  i3c: master: Fix potential UAF in i3c_device_match()
  i3c: master: Fix potential UAF in i3c_device_uevent()
  i3c: Make dev->desc locking assumptions explicit
  i3c: master: Fix use-after-free of master->this
  ...

1 files changed, 658 insertions, 0 deletions

diff --git a/fs/ufs/dir.c b/fs/ufs/dir.c
new file mode 100644
index 000000000..e62fe5667
--- /dev/null
+++ b/fs/ufs/dir.c
@@ -0,0 +1,658 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ *  linux/fs/ufs/ufs_dir.c
+ *
+ * Copyright (C) 1996
+ * Adrian Rodriguez (adrian@franklins-tower.rutgers.edu)
+ * Laboratory for Computer Science Research Computing Facility
+ * Rutgers, The State University of New Jersey
+ *
+ * swab support by Francois-Rene Rideau <fare@tunes.org> 19970406
+ *
+ * 4.4BSD (FreeBSD) support added on February 1st 1998 by
+ * Niels Kristian Bech Jensen <nkbj@image.dk> partially based
+ * on code by Martin von Loewis <martin@mira.isdn.cs.tu-berlin.de>.
+ *
+ * Migration to usage of "page cache" on May 2006 by
+ * Evgeniy Dushistov <dushistov@mail.ru> based on ext2 code base.
+ */
+
+#include <linux/time.h>
+#include <linux/fs.h>
+#include <linux/filelock.h>
+#include <linux/swap.h>
+#include <linux/iversion.h>
+
+#include "ufs_fs.h"
+#include "ufs.h"
+#include "swab.h"
+#include "util.h"
+
+/*
+ * NOTE! unlike strncmp, ufs_match returns 1 for success, 0 for failure.
+ *
+ * len <= UFS_MAXNAMLEN and de != NULL are guaranteed by caller.
+ */
+static inline int ufs_match(struct super_block *sb, int len,
+		const unsigned char *name, struct ufs_dir_entry *de)
+{
+	if (len != ufs_get_de_namlen(sb, de))
+		return 0;
+	if (!de->d_ino)
+		return 0;
+	return !memcmp(name, de->d_name, len);
+}
+
+static void ufs_commit_chunk(struct folio *folio, loff_t pos, unsigned len)
+{
+	struct address_space *mapping = folio->mapping;
+	struct inode *dir = mapping->host;
+
+	inode_inc_iversion(dir);
+	block_write_end(pos, len, len, folio);
+	if (pos+len > dir->i_size) {
+		i_size_write(dir, pos+len);
+		mark_inode_dirty(dir);
+	}
+	folio_unlock(folio);
+}
+
+static int ufs_handle_dirsync(struct inode *dir)
+{
+	int err;
+
+	err = filemap_write_and_wait(dir->i_mapping);
+	if (!err)
+		err = sync_inode_metadata(dir, 1);
+	return err;
+}
+
+ino_t ufs_inode_by_name(struct inode *dir, const struct qstr *qstr)
+{
+	ino_t res = 0;
+	struct ufs_dir_entry *de;
+	struct folio *folio;
+	
+	de = ufs_find_entry(dir, qstr, &folio);
+	if (de) {
+		res = fs32_to_cpu(dir->i_sb, de->d_ino);
+		folio_release_kmap(folio, de);
+	}
+	return res;
+}
+
+
+int ufs_set_link(struct inode *dir, struct ufs_dir_entry *de,
+		 struct folio *folio, struct inode *inode,
+		 bool update_times)
+{
+	loff_t pos = folio_pos(folio) + offset_in_folio(folio, de);
+	unsigned len = fs16_to_cpu(dir->i_sb, de->d_reclen);
+	int err;
+
+	folio_lock(folio);
+	err = ufs_prepare_chunk(folio, pos, len);
+	if (unlikely(err)) {
+		folio_unlock(folio);
+		return err;
+	}
+
+	de->d_ino = cpu_to_fs32(dir->i_sb, inode->i_ino);
+	ufs_set_de_type(dir->i_sb, de, inode->i_mode);
+
+	ufs_commit_chunk(folio, pos, len);
+	if (update_times)
+		inode_set_mtime_to_ts(dir, inode_set_ctime_current(dir));
+	mark_inode_dirty(dir);
+	return ufs_handle_dirsync(dir);
+}
+
+static bool ufs_check_folio(struct folio *folio, char *kaddr)
+{
+	struct inode *dir = folio->mapping->host;
+	struct super_block *sb = dir->i_sb;
+	unsigned offs, rec_len;
+	unsigned limit = folio_size(folio);
+	const unsigned chunk_mask = UFS_SB(sb)->s_uspi->s_dirblksize - 1;
+	struct ufs_dir_entry *p;
+	char *error;
+
+	if (dir->i_size < folio_pos(folio) + limit) {
+		limit = offset_in_folio(folio, dir->i_size);
+		if (limit & chunk_mask)
+			goto Ebadsize;
+		if (!limit)
+			goto out;
+	}
+	for (offs = 0; offs <= limit - UFS_DIR_REC_LEN(1); offs += rec_len) {
+		p = (struct ufs_dir_entry *)(kaddr + offs);
+		rec_len = fs16_to_cpu(sb, p->d_reclen);
+
+		if (rec_len < UFS_DIR_REC_LEN(1))
+			goto Eshort;
+		if (rec_len & 3)
+			goto Ealign;
+		if (rec_len < UFS_DIR_REC_LEN(ufs_get_de_namlen(sb, p)))
+			goto Enamelen;
+		if (((offs + rec_len - 1) ^ offs) & ~chunk_mask)
+			goto Espan;
+		if (fs32_to_cpu(sb, p->d_ino) > (UFS_SB(sb)->s_uspi->s_ipg *
+						  UFS_SB(sb)->s_uspi->s_ncg))
+			goto Einumber;
+	}
+	if (offs != limit)
+		goto Eend;
+out:
+	folio_set_checked(folio);
+	return true;
+
+	/* Too bad, we had an error */
+
+Ebadsize:
+	ufs_error(sb, __func__,
+		  "size of directory #%llu is not a multiple of chunk size",
+		  dir->i_ino
+	);
+	goto fail;
+Eshort:
+	error = "rec_len is smaller than minimal";
+	goto bad_entry;
+Ealign:
+	error = "unaligned directory entry";
+	goto bad_entry;
+Enamelen:
+	error = "rec_len is too small for name_len";
+	goto bad_entry;
+Espan:
+	error = "directory entry across blocks";
+	goto bad_entry;
+Einumber:
+	error = "inode out of bounds";
+bad_entry:
+	ufs_error(sb, __func__, "bad entry in directory #%llu: %s - "
+		   "offset=%llu, rec_len=%d, name_len=%d",
+		   dir->i_ino, error, folio_pos(folio) + offs,
+		   rec_len, ufs_get_de_namlen(sb, p));
+	goto fail;
+Eend:
+	p = (struct ufs_dir_entry *)(kaddr + offs);
+	ufs_error(sb, __func__,
+		   "entry in directory #%llu spans the page boundary"
+		   "offset=%llu",
+		   dir->i_ino, folio_pos(folio) + offs);
+fail:
+	return false;
+}
+
+static void *ufs_get_folio(struct inode *dir, unsigned long n,
+		struct folio **foliop)
+{
+	struct address_space *mapping = dir->i_mapping;
+	struct folio *folio = read_mapping_folio(mapping, n, NULL);
+	void *kaddr;
+
+	if (IS_ERR(folio))
+		return ERR_CAST(folio);
+	kaddr = kmap_local_folio(folio, 0);
+	if (unlikely(!folio_test_checked(folio))) {
+		if (!ufs_check_folio(folio, kaddr))
+			goto fail;
+	}
+	*foliop = folio;
+	return kaddr;
+
+fail:
+	folio_release_kmap(folio, kaddr);
+	return ERR_PTR(-EIO);
+}
+
+/*
+ * Return the offset into page `page_nr' of the last valid
+ * byte in that page, plus one.
+ */
+static unsigned
+ufs_last_byte(struct inode *inode, unsigned long page_nr)
+{
+	unsigned last_byte = inode->i_size;
+
+	last_byte -= page_nr << PAGE_SHIFT;
+	if (last_byte > PAGE_SIZE)
+		last_byte = PAGE_SIZE;
+	return last_byte;
+}
+
+static inline struct ufs_dir_entry *
+ufs_next_entry(struct super_block *sb, struct ufs_dir_entry *p)
+{
+	return (struct ufs_dir_entry *)((char *)p +
+					fs16_to_cpu(sb, p->d_reclen));
+}
+
+struct ufs_dir_entry *ufs_dotdot(struct inode *dir, struct folio **foliop)
+{
+	struct ufs_dir_entry *de = ufs_get_folio(dir, 0, foliop);
+
+	if (!IS_ERR(de))
+		return ufs_next_entry(dir->i_sb, de);
+
+	return NULL;
+}
+
+/*
+ *	ufs_find_entry()
+ *
+ * finds an entry in the specified directory with the wanted name. It
+ * returns the page in which the entry was found, and the entry itself
+ * (as a parameter - res_dir). Page is returned mapped and unlocked.
+ * Entry is guaranteed to be valid.
+ */
+struct ufs_dir_entry *ufs_find_entry(struct inode *dir, const struct qstr *qstr,
+				     struct folio **foliop)
+{
+	struct super_block *sb = dir->i_sb;
+	const unsigned char *name = qstr->name;
+	int namelen = qstr->len;
+	unsigned reclen = UFS_DIR_REC_LEN(namelen);
+	unsigned long start, n;
+	unsigned long npages = dir_pages(dir);
+	struct ufs_inode_info *ui = UFS_I(dir);
+	struct ufs_dir_entry *de;
+
+	UFSD("ENTER, dir_ino %llu, name %s, namlen %u\n", dir->i_ino, name, namelen);
+
+	if (npages == 0 || namelen > UFS_MAXNAMLEN)
+		goto out;
+
+	start = ui->i_dir_start_lookup;
+
+	if (start >= npages)
+		start = 0;
+	n = start;
+	do {
+		char *kaddr = ufs_get_folio(dir, n, foliop);
+
+		if (!IS_ERR(kaddr)) {
+			de = (struct ufs_dir_entry *)kaddr;
+			kaddr += ufs_last_byte(dir, n) - reclen;
+			while ((char *) de <= kaddr) {
+				if (ufs_match(sb, namelen, name, de))
+					goto found;
+				de = ufs_next_entry(sb, de);
+			}
+			folio_release_kmap(*foliop, kaddr);
+		}
+		if (++n >= npages)
+			n = 0;
+	} while (n != start);
+out:
+	return NULL;
+
+found:
+	ui->i_dir_start_lookup = n;
+	return de;
+}
+
+/*
+ *	Parent is locked.
+ */
+int ufs_add_link(struct dentry *dentry, struct inode *inode)
+{
+	struct inode *dir = d_inode(dentry->d_parent);
+	const unsigned char *name = dentry->d_name.name;
+	int namelen = dentry->d_name.len;
+	struct super_block *sb = dir->i_sb;
+	unsigned reclen = UFS_DIR_REC_LEN(namelen);
+	const unsigned int chunk_size = UFS_SB(sb)->s_uspi->s_dirblksize;
+	unsigned short rec_len, name_len;
+	struct folio *folio = NULL;
+	struct ufs_dir_entry *de;
+	unsigned long npages = dir_pages(dir);
+	unsigned long n;
+	loff_t pos;
+	int err;
+
+	UFSD("ENTER, name %s, namelen %u\n", name, namelen);
+
+	/*
+	 * We take care of directory expansion in the same loop.
+	 * This code plays outside i_size, so it locks the folio
+	 * to protect that region.
+	 */
+	for (n = 0; n <= npages; n++) {
+		char *kaddr = ufs_get_folio(dir, n, &folio);
+		char *dir_end;
+
+		if (IS_ERR(kaddr))
+			return PTR_ERR(kaddr);
+		folio_lock(folio);
+		dir_end = kaddr + ufs_last_byte(dir, n);
+		de = (struct ufs_dir_entry *)kaddr;
+		kaddr += folio_size(folio) - reclen;
+		while ((char *)de <= kaddr) {
+			if ((char *)de == dir_end) {
+				/* We hit i_size */
+				name_len = 0;
+				rec_len = chunk_size;
+				de->d_reclen = cpu_to_fs16(sb, chunk_size);
+				de->d_ino = 0;
+				goto got_it;
+			}
+			if (de->d_reclen == 0) {
+				ufs_error(dir->i_sb, __func__,
+					  "zero-length directory entry");
+				err = -EIO;
+				goto out_unlock;
+			}
+			err = -EEXIST;
+			if (ufs_match(sb, namelen, name, de))
+				goto out_unlock;
+			name_len = UFS_DIR_REC_LEN(ufs_get_de_namlen(sb, de));
+			rec_len = fs16_to_cpu(sb, de->d_reclen);
+			if (!de->d_ino && rec_len >= reclen)
+				goto got_it;
+			if (rec_len >= name_len + reclen)
+				goto got_it;
+			de = (struct ufs_dir_entry *) ((char *) de + rec_len);
+		}
+		folio_unlock(folio);
+		folio_release_kmap(folio, kaddr);
+	}
+	BUG();
+	return -EINVAL;
+
+got_it:
+	pos = folio_pos(folio) + offset_in_folio(folio, de);
+	err = ufs_prepare_chunk(folio, pos, rec_len);
+	if (err)
+		goto out_unlock;
+	if (de->d_ino) {
+		struct ufs_dir_entry *de1 =
+			(struct ufs_dir_entry *) ((char *) de + name_len);
+		de1->d_reclen = cpu_to_fs16(sb, rec_len - name_len);
+		de->d_reclen = cpu_to_fs16(sb, name_len);
+
+		de = de1;
+	}
+
+	ufs_set_de_namlen(sb, de, namelen);
+	memcpy(de->d_name, name, namelen + 1);
+	de->d_ino = cpu_to_fs32(sb, inode->i_ino);
+	ufs_set_de_type(sb, de, inode->i_mode);
+
+	ufs_commit_chunk(folio, pos, rec_len);
+	inode_set_mtime_to_ts(dir, inode_set_ctime_current(dir));
+
+	mark_inode_dirty(dir);
+	err = ufs_handle_dirsync(dir);
+	/* OFFSET_CACHE */
+out_put:
+	folio_release_kmap(folio, de);
+	return err;
+out_unlock:
+	folio_unlock(folio);
+	goto out_put;
+}
+
+static inline unsigned
+ufs_validate_entry(struct super_block *sb, char *base,
+		   unsigned offset, unsigned mask)
+{
+	struct ufs_dir_entry *de = (struct ufs_dir_entry*)(base + offset);
+	struct ufs_dir_entry *p = (struct ufs_dir_entry*)(base + (offset&mask));
+	while ((char*)p < (char*)de)
+		p = ufs_next_entry(sb, p);
+	return (char *)p - base;
+}
+
+
+/*
+ * This is blatantly stolen from ext2fs
+ */
+static int
+ufs_readdir(struct file *file, struct dir_context *ctx)
+{
+	loff_t pos = ctx->pos;
+	struct inode *inode = file_inode(file);
+	struct super_block *sb = inode->i_sb;
+	unsigned int offset = pos & ~PAGE_MASK;
+	unsigned long n = pos >> PAGE_SHIFT;
+	unsigned long npages = dir_pages(inode);
+	unsigned chunk_mask = ~(UFS_SB(sb)->s_uspi->s_dirblksize - 1);
+	bool need_revalidate = !inode_eq_iversion(inode, *(u64 *)file->private_data);
+	unsigned flags = UFS_SB(sb)->s_flags;
+
+	UFSD("BEGIN\n");
+
+	if (pos > inode->i_size - UFS_DIR_REC_LEN(1))
+		return 0;
+
+	for ( ; n < npages; n++, offset = 0) {
+		struct ufs_dir_entry *de;
+		struct folio *folio;
+		char *kaddr = ufs_get_folio(inode, n, &folio);
+		char *limit;
+
+		if (IS_ERR(kaddr)) {
+			ufs_error(sb, __func__,
+				  "bad page in #%llu",
+				  inode->i_ino);
+			ctx->pos += PAGE_SIZE - offset;
+			return PTR_ERR(kaddr);
+		}
+		if (unlikely(need_revalidate)) {
+			if (offset) {
+				offset = ufs_validate_entry(sb, kaddr, offset, chunk_mask);
+				ctx->pos = (n<<PAGE_SHIFT) + offset;
+			}
+			*(u64 *)file->private_data = inode_query_iversion(inode);
+			need_revalidate = false;
+		}
+		de = (struct ufs_dir_entry *)(kaddr+offset);
+		limit = kaddr + ufs_last_byte(inode, n) - UFS_DIR_REC_LEN(1);
+		for ( ;(char*)de <= limit; de = ufs_next_entry(sb, de)) {
+			if (de->d_ino) {
+				unsigned char d_type = DT_UNKNOWN;
+
+				UFSD("filldir(%s,%u)\n", de->d_name,
+				      fs32_to_cpu(sb, de->d_ino));
+				UFSD("namlen %u\n", ufs_get_de_namlen(sb, de));
+
+				if ((flags & UFS_DE_MASK) == UFS_DE_44BSD)
+					d_type = de->d_u.d_44.d_type;
+
+				if (!dir_emit(ctx, de->d_name,
+					       ufs_get_de_namlen(sb, de),
+					       fs32_to_cpu(sb, de->d_ino),
+					       d_type)) {
+					folio_release_kmap(folio, de);
+					return 0;
+				}
+			}
+			ctx->pos += fs16_to_cpu(sb, de->d_reclen);
+		}
+		folio_release_kmap(folio, kaddr);
+	}
+	return 0;
+}
+
+
+/*
+ * ufs_delete_entry deletes a directory entry by merging it with the
+ * previous entry.
+ */
+int ufs_delete_entry(struct inode *inode, struct ufs_dir_entry *dir,
+		     struct folio *folio)
+{
+	struct super_block *sb = inode->i_sb;
+	size_t from, to;
+	char *kaddr;
+	loff_t pos;
+	struct ufs_dir_entry *de, *pde = NULL;
+	int err;
+
+	UFSD("ENTER\n");
+
+	from = offset_in_folio(folio, dir);
+	to = from + fs16_to_cpu(sb, dir->d_reclen);
+	kaddr = (char *)dir - from;
+	from &= ~(UFS_SB(sb)->s_uspi->s_dirblksize - 1);
+	de = (struct ufs_dir_entry *) (kaddr + from);
+
+	UFSD("ino %u, reclen %u, namlen %u, name %s\n",
+	      fs32_to_cpu(sb, de->d_ino),
+	      fs16_to_cpu(sb, de->d_reclen),
+	      ufs_get_de_namlen(sb, de), de->d_name);
+
+	while ((char*)de < (char*)dir) {
+		if (de->d_reclen == 0) {
+			ufs_error(inode->i_sb, __func__,
+				  "zero-length directory entry");
+			return -EIO;
+		}
+		pde = de;
+		de = ufs_next_entry(sb, de);
+	}
+	if (pde)
+		from = offset_in_folio(folio, pde);
+	pos = folio_pos(folio) + from;
+	folio_lock(folio);
+	err = ufs_prepare_chunk(folio, pos, to - from);
+	if (unlikely(err)) {
+		folio_unlock(folio);
+		return err;
+	}
+	if (pde)
+		pde->d_reclen = cpu_to_fs16(sb, to - from);
+	dir->d_ino = 0;
+	ufs_commit_chunk(folio, pos, to - from);
+	inode_set_mtime_to_ts(inode, inode_set_ctime_current(inode));
+	mark_inode_dirty(inode);
+	return ufs_handle_dirsync(inode);
+}
+
+int ufs_make_empty(struct inode * inode, struct inode *dir)
+{
+	struct super_block * sb = dir->i_sb;
+	struct address_space *mapping = inode->i_mapping;
+	struct folio *folio = filemap_grab_folio(mapping, 0);
+	const unsigned int chunk_size = UFS_SB(sb)->s_uspi->s_dirblksize;
+	struct ufs_dir_entry * de;
+	int err;
+	char *kaddr;
+
+	if (IS_ERR(folio))
+		return PTR_ERR(folio);
+
+	err = ufs_prepare_chunk(folio, 0, chunk_size);
+	if (err) {
+		folio_unlock(folio);
+		goto fail;
+	}
+
+	kaddr = kmap_local_folio(folio, 0);
+	memset(kaddr, 0, folio_size(folio));
+
+	de = (struct ufs_dir_entry *)kaddr;
+
+	de->d_ino = cpu_to_fs32(sb, inode->i_ino);
+	ufs_set_de_type(sb, de, inode->i_mode);
+	ufs_set_de_namlen(sb, de, 1);
+	de->d_reclen = cpu_to_fs16(sb, UFS_DIR_REC_LEN(1));
+	strcpy (de->d_name, ".");
+	de = (struct ufs_dir_entry *)
+		((char *)de + fs16_to_cpu(sb, de->d_reclen));
+	de->d_ino = cpu_to_fs32(sb, dir->i_ino);
+	ufs_set_de_type(sb, de, dir->i_mode);
+	de->d_reclen = cpu_to_fs16(sb, chunk_size - UFS_DIR_REC_LEN(1));
+	ufs_set_de_namlen(sb, de, 2);
+	strcpy (de->d_name, "..");
+	kunmap_local(kaddr);
+
+	ufs_commit_chunk(folio, 0, chunk_size);
+	err = ufs_handle_dirsync(inode);
+fail:
+	folio_put(folio);
+	return err;
+}
+
+/*
+ * routine to check that the specified directory is empty (for rmdir)
+ */
+int ufs_empty_dir(struct inode * inode)
+{
+	struct super_block *sb = inode->i_sb;
+	struct folio *folio;
+	char *kaddr;
+	unsigned long i, npages = dir_pages(inode);
+
+	for (i = 0; i < npages; i++) {
+		struct ufs_dir_entry *de;
+
+		kaddr = ufs_get_folio(inode, i, &folio);
+		if (IS_ERR(kaddr))
+			continue;
+
+		de = (struct ufs_dir_entry *)kaddr;
+		kaddr += ufs_last_byte(inode, i) - UFS_DIR_REC_LEN(1);
+
+		while ((char *)de <= kaddr) {
+			if (de->d_reclen == 0) {
+				ufs_error(inode->i_sb, __func__,
+					"zero-length directory entry: "
+					"kaddr=%p, de=%p\n", kaddr, de);
+				goto not_empty;
+			}
+			if (de->d_ino) {
+				u16 namelen=ufs_get_de_namlen(sb, de);
+				/* check for . and .. */
+				if (de->d_name[0] != '.')
+					goto not_empty;
+				if (namelen > 2)
+					goto not_empty;
+				if (namelen < 2) {
+					if (inode->i_ino !=
+					    fs32_to_cpu(sb, de->d_ino))
+						goto not_empty;
+				} else if (de->d_name[1] != '.')
+					goto not_empty;
+			}
+			de = ufs_next_entry(sb, de);
+		}
+		folio_release_kmap(folio, kaddr);
+	}
+	return 1;
+
+not_empty:
+	folio_release_kmap(folio, kaddr);
+	return 0;
+}
+
+static int ufs_dir_open(struct inode *inode, struct file *file)
+{
+	file->private_data = kzalloc(sizeof(u64), GFP_KERNEL);
+	if (!file->private_data)
+		return -ENOMEM;
+	return 0;
+}
+
+static int ufs_dir_release(struct inode *inode, struct file *file)
+{
+	kfree(file->private_data);
+	return 0;
+}
+
+static loff_t ufs_dir_llseek(struct file *file, loff_t offset, int whence)
+{
+	return generic_llseek_cookie(file, offset, whence,
+				     (u64 *)file->private_data);
+}
+
+const struct file_operations ufs_dir_operations = {
+	.open		= ufs_dir_open,
+	.release	= ufs_dir_release,
+	.read		= generic_read_dir,
+	.iterate_shared	= ufs_readdir,
+	.fsync		= simple_fsync,
+	.llseek		= ufs_dir_llseek,
+	.setlease	= generic_setlease,
+};