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, 287 insertions, 0 deletions

diff --git a/fs/romfs/storage.c b/fs/romfs/storage.c
new file mode 100644
index 000000000..b57b3ffcb
--- /dev/null
+++ b/fs/romfs/storage.c
@@ -0,0 +1,287 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/* RomFS storage access routines
+ *
+ * Copyright © 2007 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ */
+
+#include <linux/fs.h>
+#include <linux/mtd/super.h>
+#include <linux/buffer_head.h>
+#include "internal.h"
+
+#if !defined(CONFIG_ROMFS_ON_MTD) && !defined(CONFIG_ROMFS_ON_BLOCK)
+#error no ROMFS backing store interface configured
+#endif
+
+#ifdef CONFIG_ROMFS_ON_MTD
+#define ROMFS_MTD_READ(sb, ...) mtd_read((sb)->s_mtd, ##__VA_ARGS__)
+
+/*
+ * read data from an romfs image on an MTD device
+ */
+static int romfs_mtd_read(struct super_block *sb, unsigned long pos,
+			  void *buf, size_t buflen)
+{
+	size_t rlen;
+	int ret;
+
+	ret = ROMFS_MTD_READ(sb, pos, buflen, &rlen, buf);
+	return (ret < 0 || rlen != buflen) ? -EIO : 0;
+}
+
+/*
+ * determine the length of a string in a romfs image on an MTD device
+ */
+static ssize_t romfs_mtd_strnlen(struct super_block *sb,
+				 unsigned long pos, size_t maxlen)
+{
+	ssize_t n = 0;
+	size_t segment;
+	u_char buf[16], *p;
+	size_t len;
+	int ret;
+
+	/* scan the string up to 16 bytes at a time */
+	while (maxlen > 0) {
+		segment = min_t(size_t, maxlen, 16);
+		ret = ROMFS_MTD_READ(sb, pos, segment, &len, buf);
+		if (ret < 0)
+			return ret;
+		p = memchr(buf, 0, len);
+		if (p)
+			return n + (p - buf);
+		maxlen -= len;
+		pos += len;
+		n += len;
+	}
+
+	return n;
+}
+
+/*
+ * compare a string to one in a romfs image on MTD
+ * - return 1 if matched, 0 if differ, -ve if error
+ */
+static int romfs_mtd_strcmp(struct super_block *sb, unsigned long pos,
+			    const char *str, size_t size)
+{
+	u_char buf[17];
+	size_t len, segment;
+	int ret;
+
+	/* scan the string up to 16 bytes at a time, and attempt to grab the
+	 * trailing NUL whilst we're at it */
+	buf[0] = 0xff;
+
+	while (size > 0) {
+		segment = min_t(size_t, size + 1, 17);
+		ret = ROMFS_MTD_READ(sb, pos, segment, &len, buf);
+		if (ret < 0)
+			return ret;
+		len--;
+		if (memcmp(buf, str, len) != 0)
+			return 0;
+		buf[0] = buf[len];
+		size -= len;
+		pos += len;
+		str += len;
+	}
+
+	/* check the trailing NUL was */
+	if (buf[0])
+		return 0;
+
+	return 1;
+}
+#endif /* CONFIG_ROMFS_ON_MTD */
+
+#ifdef CONFIG_ROMFS_ON_BLOCK
+/*
+ * read data from an romfs image on a block device
+ */
+static int romfs_blk_read(struct super_block *sb, unsigned long pos,
+			  void *buf, size_t buflen)
+{
+	struct buffer_head *bh;
+	unsigned long offset;
+	size_t segment;
+
+	/* copy the string up to blocksize bytes at a time */
+	while (buflen > 0) {
+		offset = pos & (ROMBSIZE - 1);
+		segment = min_t(size_t, buflen, ROMBSIZE - offset);
+		bh = sb_bread(sb, pos >> ROMBSBITS);
+		if (!bh)
+			return -EIO;
+		memcpy(buf, bh->b_data + offset, segment);
+		brelse(bh);
+		buf += segment;
+		buflen -= segment;
+		pos += segment;
+	}
+
+	return 0;
+}
+
+/*
+ * determine the length of a string in romfs on a block device
+ */
+static ssize_t romfs_blk_strnlen(struct super_block *sb,
+				 unsigned long pos, size_t limit)
+{
+	struct buffer_head *bh;
+	unsigned long offset;
+	ssize_t n = 0;
+	size_t segment;
+	u_char *buf, *p;
+
+	/* scan the string up to blocksize bytes at a time */
+	while (limit > 0) {
+		offset = pos & (ROMBSIZE - 1);
+		segment = min_t(size_t, limit, ROMBSIZE - offset);
+		bh = sb_bread(sb, pos >> ROMBSBITS);
+		if (!bh)
+			return -EIO;
+		buf = bh->b_data + offset;
+		p = memchr(buf, 0, segment);
+		brelse(bh);
+		if (p)
+			return n + (p - buf);
+		limit -= segment;
+		pos += segment;
+		n += segment;
+	}
+
+	return n;
+}
+
+/*
+ * compare a string to one in a romfs image on a block device
+ * - return 1 if matched, 0 if differ, -ve if error
+ */
+static int romfs_blk_strcmp(struct super_block *sb, unsigned long pos,
+			    const char *str, size_t size)
+{
+	struct buffer_head *bh;
+	unsigned long offset;
+	size_t segment;
+	bool matched, terminated = false;
+
+	/* compare string up to a block at a time */
+	while (size > 0) {
+		offset = pos & (ROMBSIZE - 1);
+		segment = min_t(size_t, size, ROMBSIZE - offset);
+		bh = sb_bread(sb, pos >> ROMBSBITS);
+		if (!bh)
+			return -EIO;
+		matched = (memcmp(bh->b_data + offset, str, segment) == 0);
+
+		size -= segment;
+		pos += segment;
+		str += segment;
+		if (matched && size == 0 && offset + segment < ROMBSIZE) {
+			if (!bh->b_data[offset + segment])
+				terminated = true;
+			else
+				matched = false;
+		}
+		brelse(bh);
+		if (!matched)
+			return 0;
+	}
+
+	if (!terminated) {
+		/* the terminating NUL must be on the first byte of the next
+		 * block */
+		BUG_ON((pos & (ROMBSIZE - 1)) != 0);
+		bh = sb_bread(sb, pos >> ROMBSBITS);
+		if (!bh)
+			return -EIO;
+		matched = !bh->b_data[0];
+		brelse(bh);
+		if (!matched)
+			return 0;
+	}
+
+	return 1;
+}
+#endif /* CONFIG_ROMFS_ON_BLOCK */
+
+/*
+ * read data from the romfs image
+ */
+int romfs_dev_read(struct super_block *sb, unsigned long pos,
+		   void *buf, size_t buflen)
+{
+	size_t limit;
+
+	limit = romfs_maxsize(sb);
+	if (pos >= limit || buflen > limit - pos)
+		return -EIO;
+
+#ifdef CONFIG_ROMFS_ON_MTD
+	if (sb->s_mtd)
+		return romfs_mtd_read(sb, pos, buf, buflen);
+#endif
+#ifdef CONFIG_ROMFS_ON_BLOCK
+	if (sb->s_bdev)
+		return romfs_blk_read(sb, pos, buf, buflen);
+#endif
+	return -EIO;
+}
+
+/*
+ * determine the length of a string in romfs
+ */
+ssize_t romfs_dev_strnlen(struct super_block *sb,
+			  unsigned long pos, size_t maxlen)
+{
+	size_t limit;
+
+	limit = romfs_maxsize(sb);
+	if (pos >= limit)
+		return -EIO;
+	if (maxlen > limit - pos)
+		maxlen = limit - pos;
+
+#ifdef CONFIG_ROMFS_ON_MTD
+	if (sb->s_mtd)
+		return romfs_mtd_strnlen(sb, pos, maxlen);
+#endif
+#ifdef CONFIG_ROMFS_ON_BLOCK
+	if (sb->s_bdev)
+		return romfs_blk_strnlen(sb, pos, maxlen);
+#endif
+	return -EIO;
+}
+
+/*
+ * compare a string to one in romfs
+ * - the string to be compared to, str, may not be NUL-terminated; instead the
+ *   string is of the specified size
+ * - return 1 if matched, 0 if differ, -ve if error
+ */
+int romfs_dev_strcmp(struct super_block *sb, unsigned long pos,
+		     const char *str, size_t size)
+{
+	size_t limit;
+
+	limit = romfs_maxsize(sb);
+	if (pos >= limit)
+		return -EIO;
+	if (size > ROMFS_MAXFN)
+		return -ENAMETOOLONG;
+	if (size + 1 > limit - pos)
+		return -EIO;
+
+#ifdef CONFIG_ROMFS_ON_MTD
+	if (sb->s_mtd)
+		return romfs_mtd_strcmp(sb, pos, str, size);
+#endif
+#ifdef CONFIG_ROMFS_ON_BLOCK
+	if (sb->s_bdev)
+		return romfs_blk_strcmp(sb, pos, str, size);
+#endif
+	return -EIO;
+}