Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextgrafted

Pull networking updates from Jakub Kicinski:
 "Core:

   - Add dedicated kmem_cache for typical/small skb->head, avoid having
     to access struct page at kfree time, and improve memory use.

   - Introduce sysctl to set default RPS configuration for new netdevs.

   - Define Netlink protocol specification format which can be used to
     describe messages used by each family and auto-generate parsers.
     Add tools for generating kernel data structures and uAPI headers.

   - Expose all net/core sysctls inside netns.

   - Remove 4s sleep in netpoll if carrier is instantly detected on
     boot.

   - Add configurable limit of MDB entries per port, and port-vlan.

   - Continue populating drop reasons throughout the stack.

   - Retire a handful of legacy Qdiscs and classifiers.

  Protocols:

   - Support IPv4 big TCP (TSO frames larger than 64kB).

   - Add IP_LOCAL_PORT_RANGE socket option, to control local port range
     on socket by socket basis.

   - Track and report in procfs number of MPTCP sockets used.

   - Support mixing IPv4 and IPv6 flows in the in-kernel MPTCP path
     manager.

   - IPv6: don't check net.ipv6.route.max_size and rely on garbage
     collection to free memory (similarly to IPv4).

   - Support Penultimate Segment Pop (PSP) flavor in SRv6 (RFC8986).

   - ICMP: add per-rate limit counters.

   - Add support for user scanning requests in ieee802154.

   - Remove static WEP support.

   - Support minimal Wi-Fi 7 Extremely High Throughput (EHT) rate
     reporting.

   - WiFi 7 EHT channel puncturing support (client & AP).

  BPF:

   - Add a rbtree data structure following the "next-gen data structure"
     precedent set by recently added linked list, that is, by using
     kfunc + kptr instead of adding a new BPF map type.

   - Expose XDP hints via kfuncs with initial support for RX hash and
     timestamp metadata.

   - Add BPF_F_NO_TUNNEL_KEY extension to bpf_skb_set_tunnel_key to
     better support decap on GRE tunnel devices not operating in collect
     metadata.

   - Improve x86 JIT's codegen for PROBE_MEM runtime error checks.

   - Remove the need for trace_printk_lock for bpf_trace_printk and
     bpf_trace_vprintk helpers.

   - Extend libbpf's bpf_tracing.h support for tracing arguments of
     kprobes/uprobes and syscall as a special case.

   - Significantly reduce the search time for module symbols by
     livepatch and BPF.

   - Enable cpumasks to be used as kptrs, which is useful for tracing
     programs tracking which tasks end up running on which CPUs in
     different time intervals.

   - Add support for BPF trampoline on s390x and riscv64.

   - Add capability to export the XDP features supported by the NIC.

   - Add __bpf_kfunc tag for marking kernel functions as kfuncs.

   - Add cgroup.memory=nobpf kernel parameter option to disable BPF
     memory accounting for container environments.

  Netfilter:

   - Remove the CLUSTERIP target. It has been marked as obsolete for
     years, and we still have WARN splats wrt races of the out-of-band
     /proc interface installed by this target.

   - Add 'destroy' commands to nf_tables. They are identical to the
     existing 'delete' commands, but do not return an error if the
     referenced object (set, chain, rule...) did not exist.

  Driver API:

   - Improve cpumask_local_spread() locality to help NICs set the right
     IRQ affinity on AMD platforms.

   - Separate C22 and C45 MDIO bus transactions more clearly.

   - Introduce new DCB table to control DSCP rewrite on egress.

   - Support configuration of Physical Layer Collision Avoidance (PLCA)
     Reconciliation Sublayer (RS) (802.3cg-2019). Modern version of
     shared medium Ethernet.

   - Support for MAC Merge layer (IEEE 802.3-2018 clause 99). Allowing
     preemption of low priority frames by high priority frames.

   - Add support for controlling MACSec offload using netlink SET.

   - Rework devlink instance refcounts to allow registration and
     de-registration under the instance lock. Split the code into
     multiple files, drop some of the unnecessarily granular locks and
     factor out common parts of netlink operation handling.

   - Add TX frame aggregation parameters (for USB drivers).

   - Add a new attr TCA_EXT_WARN_MSG to report TC (offload) warning
     messages with notifications for debug.

   - Allow offloading of UDP NEW connections via act_ct.

   - Add support for per action HW stats in TC.

   - Support hardware miss to TC action (continue processing in SW from
     a specific point in the action chain).

   - Warn if old Wireless Extension user space interface is used with
     modern cfg80211/mac80211 drivers. Do not support Wireless
     Extensions for Wi-Fi 7 devices at all. Everyone should switch to
     using nl80211 interface instead.

   - Improve the CAN bit timing configuration. Use extack to return
     error messages directly to user space, update the SJW handling,
     including the definition of a new default value that will benefit
     CAN-FD controllers, by increasing their oscillator tolerance.

  New hardware / drivers:

   - Ethernet:
      - nVidia BlueField-3 support (control traffic driver)
      - Ethernet support for imx93 SoCs
      - Motorcomm yt8531 gigabit Ethernet PHY
      - onsemi NCN26000 10BASE-T1S PHY (with support for PLCA)
      - Microchip LAN8841 PHY (incl. cable diagnostics and PTP)
      - Amlogic gxl MDIO mux

   - WiFi:
      - RealTek RTL8188EU (rtl8xxxu)
      - Qualcomm Wi-Fi 7 devices (ath12k)

   - CAN:
      - Renesas R-Car V4H

  Drivers:

   - Bluetooth:
      - Set Per Platform Antenna Gain (PPAG) for Intel controllers.

   - Ethernet NICs:
      - Intel (1G, igc):
         - support TSN / Qbv / packet scheduling features of i226 model
      - Intel (100G, ice):
         - use GNSS subsystem instead of TTY
         - multi-buffer XDP support
         - extend support for GPIO pins to E823 devices
      - nVidia/Mellanox:
         - update the shared buffer configuration on PFC commands
         - implement PTP adjphase function for HW offset control
         - TC support for Geneve and GRE with VF tunnel offload
         - more efficient crypto key management method
         - multi-port eswitch support
      - Netronome/Corigine:
         - add DCB IEEE support
         - support IPsec offloading for NFP3800
      - Freescale/NXP (enetc):
         - support XDP_REDIRECT for XDP non-linear buffers
         - improve reconfig, avoid link flap and waiting for idle
         - support MAC Merge layer
      - Other NICs:
         - sfc/ef100: add basic devlink support for ef100
         - ionic: rx_push mode operation (writing descriptors via MMIO)
         - bnxt: use the auxiliary bus abstraction for RDMA
         - r8169: disable ASPM and reset bus in case of tx timeout
         - cpsw: support QSGMII mode for J721e CPSW9G
         - cpts: support pulse-per-second output
         - ngbe: add an mdio bus driver
         - usbnet: optimize usbnet_bh() by avoiding unnecessary queuing
         - r8152: handle devices with FW with NCM support
         - amd-xgbe: support 10Mbps, 2.5GbE speeds and rx-adaptation
         - virtio-net: support multi buffer XDP
         - virtio/vsock: replace virtio_vsock_pkt with sk_buff
         - tsnep: XDP support

   - Ethernet high-speed switches:
      - nVidia/Mellanox (mlxsw):
         - add support for latency TLV (in FW control messages)
      - Microchip (sparx5):
         - separate explicit and implicit traffic forwarding rules, make
           the implicit rules always active
         - add support for egress DSCP rewrite
         - IS0 VCAP support (Ingress Classification)
         - IS2 VCAP filters (protos, L3 addrs, L4 ports, flags, ToS
           etc.)
         - ES2 VCAP support (Egress Access Control)
         - support for Per-Stream Filtering and Policing (802.1Q,
           8.6.5.1)

   - Ethernet embedded switches:
      - Marvell (mv88e6xxx):
         - add MAB (port auth) offload support
         - enable PTP receive for mv88e6390
      - NXP (ocelot):
         - support MAC Merge layer
         - support for the the vsc7512 internal copper phys
      - Microchip:
         - lan9303: convert to PHYLINK
         - lan966x: support TC flower filter statistics
         - lan937x: PTP support for KSZ9563/KSZ8563 and LAN937x
         - lan937x: support Credit Based Shaper configuration
         - ksz9477: support Energy Efficient Ethernet
      - other:
         - qca8k: convert to regmap read/write API, use bulk operations
         - rswitch: Improve TX timestamp accuracy

   - Intel WiFi (iwlwifi):
      - EHT (Wi-Fi 7) rate reporting
      - STEP equalizer support: transfer some STEP (connection to radio
        on platforms with integrated wifi) related parameters from the
        BIOS to the firmware.

   - Qualcomm 802.11ax WiFi (ath11k):
      - IPQ5018 support
      - Fine Timing Measurement (FTM) responder role support
      - channel 177 support

   - MediaTek WiFi (mt76):
      - per-PHY LED support
      - mt7996: EHT (Wi-Fi 7) support
      - Wireless Ethernet Dispatch (WED) reset support
      - switch to using page pool allocator

   - RealTek WiFi (rtw89):
      - support new version of Bluetooth co-existance

   - Mobile:
      - rmnet: support TX aggregation"

* tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1872 commits)
  page_pool: add a comment explaining the fragment counter usage
  net: ethtool: fix __ethtool_dev_mm_supported() implementation
  ethtool: pse-pd: Fix double word in comments
  xsk: add linux/vmalloc.h to xsk.c
  sefltests: netdevsim: wait for devlink instance after netns removal
  selftest: fib_tests: Always cleanup before exit
  net/mlx5e: Align IPsec ASO result memory to be as required by hardware
  net/mlx5e: TC, Set CT miss to the specific ct action instance
  net/mlx5e: Rename CHAIN_TO_REG to MAPPED_OBJ_TO_REG
  net/mlx5: Refactor tc miss handling to a single function
  net/mlx5: Kconfig: Make tc offload depend on tc skb extension
  net/sched: flower: Support hardware miss to tc action
  net/sched: flower: Move filter handle initialization earlier
  net/sched: cls_api: Support hardware miss to tc action
  net/sched: Rename user cookie and act cookie
  sfc: fix builds without CONFIG_RTC_LIB
  sfc: clean up some inconsistent indentings
  net/mlx4_en: Introduce flexible array to silence overflow warning
  net: lan966x: Fix possible deadlock inside PTP
  net/ulp: Remove redundant ->clone() test in inet_clone_ulp().
  ...

1 files changed, 377 insertions, 0 deletions

diff --git a/fs/fat/misc.c b/fs/fat/misc.c
new file mode 100644
index 000000000..7e5d6ae30
--- /dev/null
+++ b/fs/fat/misc.c
@@ -0,0 +1,377 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ *  linux/fs/fat/misc.c
+ *
+ *  Written 1992,1993 by Werner Almesberger
+ *  22/11/2000 - Fixed fat_date_unix2dos for dates earlier than 01/01/1980
+ *		 and date_dos2unix for date==0 by Igor Zhbanov(bsg@uniyar.ac.ru)
+ */
+
+#include "fat.h"
+#include <linux/iversion.h>
+
+/*
+ * fat_fs_error reports a file system problem that might indicate fa data
+ * corruption/inconsistency. Depending on 'errors' mount option the
+ * panic() is called, or error message is printed FAT and nothing is done,
+ * or filesystem is remounted read-only (default behavior).
+ * In case the file system is remounted read-only, it can be made writable
+ * again by remounting it.
+ */
+void __fat_fs_error(struct super_block *sb, int report, const char *fmt, ...)
+{
+	struct fat_mount_options *opts = &MSDOS_SB(sb)->options;
+	va_list args;
+	struct va_format vaf;
+
+	if (report) {
+		va_start(args, fmt);
+		vaf.fmt = fmt;
+		vaf.va = &args;
+		fat_msg(sb, KERN_ERR, "error, %pV", &vaf);
+		va_end(args);
+	}
+
+	if (opts->errors == FAT_ERRORS_PANIC)
+		panic("FAT-fs (%s): fs panic from previous error\n", sb->s_id);
+	else if (opts->errors == FAT_ERRORS_RO && !sb_rdonly(sb)) {
+		sb->s_flags |= SB_RDONLY;
+		fat_msg(sb, KERN_ERR, "Filesystem has been set read-only");
+	}
+}
+EXPORT_SYMBOL_GPL(__fat_fs_error);
+
+/**
+ * _fat_msg() - Print a preformatted FAT message based on a superblock.
+ * @sb: A pointer to a &struct super_block
+ * @level: A Kernel printk level constant
+ * @fmt: The printf-style format string to print.
+ *
+ * Everything that is not fat_fs_error() should be fat_msg().
+ *
+ * fat_msg() wraps _fat_msg() for printk indexing.
+ */
+void _fat_msg(struct super_block *sb, const char *level, const char *fmt, ...)
+{
+	struct va_format vaf;
+	va_list args;
+
+	va_start(args, fmt);
+	vaf.fmt = fmt;
+	vaf.va = &args;
+	_printk(FAT_PRINTK_PREFIX "%pV\n", level, sb->s_id, &vaf);
+	va_end(args);
+}
+
+/* Flushes the number of free clusters on FAT32 */
+/* XXX: Need to write one per FSINFO block.  Currently only writes 1 */
+int fat_clusters_flush(struct super_block *sb)
+{
+	struct msdos_sb_info *sbi = MSDOS_SB(sb);
+	struct buffer_head *bh;
+	struct fat_boot_fsinfo *fsinfo;
+
+	if (!is_fat32(sbi))
+		return 0;
+
+	bh = sb_bread(sb, sbi->fsinfo_sector);
+	if (bh == NULL) {
+		fat_msg(sb, KERN_ERR, "bread failed in fat_clusters_flush");
+		return -EIO;
+	}
+
+	fsinfo = (struct fat_boot_fsinfo *)bh->b_data;
+	/* Sanity check */
+	if (!IS_FSINFO(fsinfo)) {
+		fat_msg(sb, KERN_ERR, "Invalid FSINFO signature: "
+		       "0x%08x, 0x%08x (sector = %lu)",
+		       le32_to_cpu(fsinfo->signature1),
+		       le32_to_cpu(fsinfo->signature2),
+		       sbi->fsinfo_sector);
+	} else {
+		if (sbi->free_clusters != -1)
+			fsinfo->free_clusters = cpu_to_le32(sbi->free_clusters);
+		if (sbi->prev_free != -1)
+			fsinfo->next_cluster = cpu_to_le32(sbi->prev_free);
+		mark_buffer_dirty(bh);
+	}
+	brelse(bh);
+
+	return 0;
+}
+
+/*
+ * fat_chain_add() adds a new cluster to the chain of clusters represented
+ * by inode.
+ */
+int fat_chain_add(struct inode *inode, int new_dclus, int nr_cluster)
+{
+	struct super_block *sb = inode->i_sb;
+	struct msdos_sb_info *sbi = MSDOS_SB(sb);
+	int ret, new_fclus, last;
+
+	/*
+	 * We must locate the last cluster of the file to add this new
+	 * one (new_dclus) to the end of the link list (the FAT).
+	 */
+	last = new_fclus = 0;
+	if (MSDOS_I(inode)->i_start) {
+		int fclus, dclus;
+
+		ret = fat_get_cluster(inode, FAT_ENT_EOF, &fclus, &dclus);
+		if (ret < 0)
+			return ret;
+		new_fclus = fclus + 1;
+		last = dclus;
+	}
+
+	/* add new one to the last of the cluster chain */
+	if (last) {
+		struct fat_entry fatent;
+
+		fatent_init(&fatent);
+		ret = fat_ent_read(inode, &fatent, last);
+		if (ret >= 0) {
+			int wait = inode_needs_sync(inode);
+			ret = fat_ent_write(inode, &fatent, new_dclus, wait);
+			fatent_brelse(&fatent);
+		}
+		if (ret < 0)
+			return ret;
+		/*
+		 * FIXME:Although we can add this cache, fat_cache_add() is
+		 * assuming to be called after linear search with fat_cache_id.
+		 */
+//		fat_cache_add(inode, new_fclus, new_dclus);
+	} else {
+		MSDOS_I(inode)->i_start = new_dclus;
+		MSDOS_I(inode)->i_logstart = new_dclus;
+		/*
+		 * Since generic_write_sync() synchronizes regular files later,
+		 * we sync here only directories.
+		 */
+		if (S_ISDIR(inode->i_mode) && IS_DIRSYNC(inode)) {
+			ret = fat_sync_inode(inode);
+			if (ret)
+				return ret;
+		} else
+			mark_inode_dirty(inode);
+	}
+	if (new_fclus != (inode->i_blocks >> (sbi->cluster_bits - 9))) {
+		fat_fs_error(sb, "clusters badly computed (%d != %llu)",
+			     new_fclus,
+			     (llu)(inode->i_blocks >> (sbi->cluster_bits - 9)));
+		fat_cache_inval_inode(inode);
+	}
+	inode->i_blocks += nr_cluster << (sbi->cluster_bits - 9);
+
+	return 0;
+}
+
+/*
+ * The epoch of FAT timestamp is 1980.
+ *     :  bits :     value
+ * date:  0 -  4: day	(1 -  31)
+ * date:  5 -  8: month	(1 -  12)
+ * date:  9 - 15: year	(0 - 127) from 1980
+ * time:  0 -  4: sec	(0 -  29) 2sec counts
+ * time:  5 - 10: min	(0 -  59)
+ * time: 11 - 15: hour	(0 -  23)
+ */
+#define SECS_PER_MIN	60
+#define SECS_PER_HOUR	(60 * 60)
+#define SECS_PER_DAY	(SECS_PER_HOUR * 24)
+/* days between 1.1.70 and 1.1.80 (2 leap days) */
+#define DAYS_DELTA	(365 * 10 + 2)
+/* 120 (2100 - 1980) isn't leap year */
+#define YEAR_2100	120
+#define IS_LEAP_YEAR(y)	(!((y) & 3) && (y) != YEAR_2100)
+
+/* Linear day numbers of the respective 1sts in non-leap years. */
+static long days_in_year[] = {
+	/* Jan  Feb  Mar  Apr  May  Jun  Jul  Aug  Sep  Oct  Nov  Dec */
+	0,   0,  31,  59,  90, 120, 151, 181, 212, 243, 273, 304, 334, 0, 0, 0,
+};
+
+static inline int fat_tz_offset(const struct msdos_sb_info *sbi)
+{
+	return (sbi->options.tz_set ?
+	       -sbi->options.time_offset :
+	       sys_tz.tz_minuteswest) * SECS_PER_MIN;
+}
+
+/* Convert a FAT time/date pair to a UNIX date (seconds since 1 1 70). */
+void fat_time_fat2unix(struct msdos_sb_info *sbi, struct timespec64 *ts,
+		       __le16 __time, __le16 __date, u8 time_cs)
+{
+	u16 time = le16_to_cpu(__time), date = le16_to_cpu(__date);
+	time64_t second;
+	long day, leap_day, month, year;
+
+	year  = date >> 9;
+	month = max(1, (date >> 5) & 0xf);
+	day   = max(1, date & 0x1f) - 1;
+
+	leap_day = (year + 3) / 4;
+	if (year > YEAR_2100)		/* 2100 isn't leap year */
+		leap_day--;
+	if (IS_LEAP_YEAR(year) && month > 2)
+		leap_day++;
+
+	second =  (time & 0x1f) << 1;
+	second += ((time >> 5) & 0x3f) * SECS_PER_MIN;
+	second += (time >> 11) * SECS_PER_HOUR;
+	second += (time64_t)(year * 365 + leap_day
+		   + days_in_year[month] + day
+		   + DAYS_DELTA) * SECS_PER_DAY;
+
+	second += fat_tz_offset(sbi);
+
+	if (time_cs) {
+		ts->tv_sec = second + (time_cs / 100);
+		ts->tv_nsec = (time_cs % 100) * 10000000;
+	} else {
+		ts->tv_sec = second;
+		ts->tv_nsec = 0;
+	}
+}
+
+/* Export fat_time_fat2unix() for the fat_test KUnit tests. */
+EXPORT_SYMBOL_GPL(fat_time_fat2unix);
+
+/* Convert linear UNIX date to a FAT time/date pair. */
+void fat_time_unix2fat(struct msdos_sb_info *sbi, struct timespec64 *ts,
+		       __le16 *time, __le16 *date, u8 *time_cs)
+{
+	struct tm tm;
+	time64_to_tm(ts->tv_sec, -fat_tz_offset(sbi), &tm);
+
+	/*  FAT can only support year between 1980 to 2107 */
+	if (tm.tm_year < 1980 - 1900) {
+		*time = 0;
+		*date = cpu_to_le16((0 << 9) | (1 << 5) | 1);
+		if (time_cs)
+			*time_cs = 0;
+		return;
+	}
+	if (tm.tm_year > 2107 - 1900) {
+		*time = cpu_to_le16((23 << 11) | (59 << 5) | 29);
+		*date = cpu_to_le16((127 << 9) | (12 << 5) | 31);
+		if (time_cs)
+			*time_cs = 199;
+		return;
+	}
+
+	/* from 1900 -> from 1980 */
+	tm.tm_year -= 80;
+	/* 0~11 -> 1~12 */
+	tm.tm_mon++;
+	/* 0~59 -> 0~29(2sec counts) */
+	tm.tm_sec >>= 1;
+
+	*time = cpu_to_le16(tm.tm_hour << 11 | tm.tm_min << 5 | tm.tm_sec);
+	*date = cpu_to_le16(tm.tm_year << 9 | tm.tm_mon << 5 | tm.tm_mday);
+	if (time_cs)
+		*time_cs = (ts->tv_sec & 1) * 100 + ts->tv_nsec / 10000000;
+}
+EXPORT_SYMBOL_GPL(fat_time_unix2fat);
+
+static inline struct timespec64 fat_timespec64_trunc_2secs(struct timespec64 ts)
+{
+	return (struct timespec64){ ts.tv_sec & ~1ULL, 0 };
+}
+
+/*
+ * truncate atime to 24 hour granularity (00:00:00 in local timezone)
+ */
+struct timespec64 fat_truncate_atime(const struct msdos_sb_info *sbi,
+				     const struct timespec64 *ts)
+{
+	/* to localtime */
+	time64_t seconds = ts->tv_sec - fat_tz_offset(sbi);
+	s32 remainder;
+
+	div_s64_rem(seconds, SECS_PER_DAY, &remainder);
+	/* to day boundary, and back to unix time */
+	seconds = seconds + fat_tz_offset(sbi) - remainder;
+
+	return (struct timespec64){ seconds, 0 };
+}
+
+/*
+ * truncate mtime to 2 second granularity
+ */
+struct timespec64 fat_truncate_mtime(const struct msdos_sb_info *sbi,
+				     const struct timespec64 *ts)
+{
+	return fat_timespec64_trunc_2secs(*ts);
+}
+
+/*
+ * truncate the various times with appropriate granularity:
+ *   all times in root node are always 0
+ */
+int fat_truncate_time(struct inode *inode, struct timespec64 *now, int flags)
+{
+	struct msdos_sb_info *sbi = MSDOS_SB(inode->i_sb);
+	struct timespec64 ts;
+
+	if (inode->i_ino == MSDOS_ROOT_INO)
+		return 0;
+
+	if (now == NULL) {
+		now = &ts;
+		ts = current_time(inode);
+	}
+
+	if (flags & S_ATIME)
+		inode->i_atime = fat_truncate_atime(sbi, now);
+	/*
+	 * ctime and mtime share the same on-disk field, and should be
+	 * identical in memory. all mtime updates will be applied to ctime,
+	 * but ctime updates are ignored.
+	 */
+	if (flags & S_MTIME)
+		inode->i_mtime = inode->i_ctime = fat_truncate_mtime(sbi, now);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(fat_truncate_time);
+
+int fat_update_time(struct inode *inode, struct timespec64 *now, int flags)
+{
+	int dirty_flags = 0;
+
+	if (inode->i_ino == MSDOS_ROOT_INO)
+		return 0;
+
+	if (flags & (S_ATIME | S_CTIME | S_MTIME)) {
+		fat_truncate_time(inode, now, flags);
+		if (inode->i_sb->s_flags & SB_LAZYTIME)
+			dirty_flags |= I_DIRTY_TIME;
+		else
+			dirty_flags |= I_DIRTY_SYNC;
+	}
+
+	if ((flags & S_VERSION) && inode_maybe_inc_iversion(inode, false))
+		dirty_flags |= I_DIRTY_SYNC;
+
+	__mark_inode_dirty(inode, dirty_flags);
+	return 0;
+}
+EXPORT_SYMBOL_GPL(fat_update_time);
+
+int fat_sync_bhs(struct buffer_head **bhs, int nr_bhs)
+{
+	int i, err = 0;
+
+	for (i = 0; i < nr_bhs; i++)
+		write_dirty_buffer(bhs[i], 0);
+
+	for (i = 0; i < nr_bhs; i++) {
+		wait_on_buffer(bhs[i]);
+		if (!err && !buffer_uptodate(bhs[i]))
+			err = -EIO;
+	}
+	return err;
+}