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authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-23 13:28:57 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-23 13:28:57 -0700
commit4352b8aee98005853aa63f57d6377282de17a33f (patch)
tree27614d7a9ef05c32d089004e104364ce42324837 /fs/exfat/misc.c
downloadlinux-stable-4352b8aee98005853aa63f57d6377282de17a33f.tar.gz
linux-stable-4352b8aee98005853aa63f57d6377282de17a33f.zip
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 ...
Diffstat (limited to 'fs/exfat/misc.c')
-rw-r--r--fs/exfat/misc.c207
1 files changed, 207 insertions, 0 deletions
diff --git a/fs/exfat/misc.c b/fs/exfat/misc.c
new file mode 100644
index 000000000..6f11a96a4
--- /dev/null
+++ b/fs/exfat/misc.c
@@ -0,0 +1,207 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * 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)
+ * Copyright (C) 2012-2013 Samsung Electronics Co., Ltd.
+ */
+
+#include <linux/time.h>
+#include <linux/fs.h>
+#include <linux/slab.h>
+#include <linux/buffer_head.h>
+#include <linux/blk_types.h>
+
+#include "exfat_raw.h"
+#include "exfat_fs.h"
+
+/*
+ * exfat_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 __exfat_fs_error(struct super_block *sb, int report, const char *fmt, ...)
+{
+ struct exfat_mount_options *opts = &EXFAT_SB(sb)->options;
+ va_list args;
+ struct va_format vaf;
+
+ if (report) {
+ va_start(args, fmt);
+ vaf.fmt = fmt;
+ vaf.va = &args;
+ exfat_err(sb, "error, %pV", &vaf);
+ va_end(args);
+ }
+
+ if (opts->errors == EXFAT_ERRORS_PANIC) {
+ panic("exFAT-fs (%s): fs panic from previous error\n",
+ sb->s_id);
+ } else if (opts->errors == EXFAT_ERRORS_RO && !sb_rdonly(sb)) {
+ sb->s_flags |= SB_RDONLY;
+ exfat_err(sb, "Filesystem has been set read-only");
+ }
+}
+
+#define SECS_PER_MIN (60)
+#define TIMEZONE_SEC(x) ((x) * 15 * SECS_PER_MIN)
+
+static void exfat_adjust_tz(struct timespec64 *ts, u8 tz_off)
+{
+ if (tz_off <= 0x3F)
+ ts->tv_sec -= TIMEZONE_SEC(tz_off);
+ else /* 0x40 <= (tz_off & 0x7F) <=0x7F */
+ ts->tv_sec += TIMEZONE_SEC(0x80 - tz_off);
+}
+
+static inline int exfat_tz_offset(struct exfat_sb_info *sbi)
+{
+ if (sbi->options.sys_tz)
+ return -sys_tz.tz_minuteswest;
+ return sbi->options.time_offset;
+}
+
+/* Convert a EXFAT time/date pair to a UNIX date (seconds since 1 1 70). */
+void exfat_get_entry_time(struct exfat_sb_info *sbi, struct timespec64 *ts,
+ u8 tz, __le16 time, __le16 date, u8 time_cs)
+{
+ u16 t = le16_to_cpu(time);
+ u16 d = le16_to_cpu(date);
+
+ ts->tv_sec = mktime64(1980 + (d >> 9), d >> 5 & 0x000F, d & 0x001F,
+ t >> 11, (t >> 5) & 0x003F, (t & 0x001F) << 1);
+
+
+ /* time_cs field represent 0 ~ 199cs(1990 ms) */
+ if (time_cs) {
+ ts->tv_sec += time_cs / 100;
+ ts->tv_nsec = (time_cs % 100) * 10 * NSEC_PER_MSEC;
+ } else
+ ts->tv_nsec = 0;
+
+ if (tz & EXFAT_TZ_VALID)
+ /* Adjust timezone to UTC0. */
+ exfat_adjust_tz(ts, tz & ~EXFAT_TZ_VALID);
+ else
+ ts->tv_sec -= exfat_tz_offset(sbi) * SECS_PER_MIN;
+}
+
+/* Convert linear UNIX date to a EXFAT time/date pair. */
+void exfat_set_entry_time(struct exfat_sb_info *sbi, struct timespec64 *ts,
+ u8 *tz, __le16 *time, __le16 *date, u8 *time_cs)
+{
+ struct tm tm;
+ u16 t, d;
+
+ time64_to_tm(ts->tv_sec, 0, &tm);
+ t = (tm.tm_hour << 11) | (tm.tm_min << 5) | (tm.tm_sec >> 1);
+ d = ((tm.tm_year - 80) << 9) | ((tm.tm_mon + 1) << 5) | tm.tm_mday;
+
+ *time = cpu_to_le16(t);
+ *date = cpu_to_le16(d);
+
+ /* time_cs field represent 0 ~ 199cs(1990 ms) */
+ if (time_cs)
+ *time_cs = (tm.tm_sec & 1) * 100 +
+ ts->tv_nsec / (10 * NSEC_PER_MSEC);
+
+ /*
+ * Record 00h value for OffsetFromUtc field and 1 value for OffsetValid
+ * to indicate that local time and UTC are the same.
+ */
+ *tz = EXFAT_TZ_VALID;
+}
+
+/*
+ * The timestamp for access_time has double seconds granularity.
+ * (There is no 10msIncrement field for access_time unlike create/modify_time)
+ * atime also has only a 2-second resolution.
+ */
+void exfat_truncate_atime(struct timespec64 *ts)
+{
+ ts->tv_sec = round_down(ts->tv_sec, 2);
+ ts->tv_nsec = 0;
+}
+
+void exfat_truncate_inode_atime(struct inode *inode)
+{
+ struct timespec64 atime = inode_get_atime(inode);
+
+ exfat_truncate_atime(&atime);
+ inode_set_atime_to_ts(inode, atime);
+}
+
+u16 exfat_calc_chksum16(void *data, int len, u16 chksum, int type)
+{
+ int i;
+ u8 *c = (u8 *)data;
+
+ for (i = 0; i < len; i++, c++) {
+ if (unlikely(type == CS_DIR_ENTRY && (i == 2 || i == 3)))
+ continue;
+ chksum = ((chksum << 15) | (chksum >> 1)) + *c;
+ }
+ return chksum;
+}
+
+u32 exfat_calc_chksum32(void *data, int len, u32 chksum, int type)
+{
+ int i;
+ u8 *c = (u8 *)data;
+
+ for (i = 0; i < len; i++, c++) {
+ if (unlikely(type == CS_BOOT_SECTOR &&
+ (i == 106 || i == 107 || i == 112)))
+ continue;
+ chksum = ((chksum << 31) | (chksum >> 1)) + *c;
+ }
+ return chksum;
+}
+
+int exfat_update_bh(struct buffer_head *bh, int sync)
+{
+ int err = 0;
+
+ set_buffer_uptodate(bh);
+ mark_buffer_dirty(bh);
+
+ if (sync)
+ err = sync_dirty_buffer(bh);
+
+ return err;
+}
+
+int exfat_update_bhs(struct buffer_head **bhs, int nr_bhs, int sync)
+{
+ int i, err = 0;
+
+ for (i = 0; i < nr_bhs; i++) {
+ set_buffer_uptodate(bhs[i]);
+ mark_buffer_dirty(bhs[i]);
+ if (sync)
+ write_dirty_buffer(bhs[i], REQ_SYNC);
+ }
+
+ for (i = 0; i < nr_bhs && sync; i++) {
+ wait_on_buffer(bhs[i]);
+ if (!err && !buffer_uptodate(bhs[i]))
+ err = -EIO;
+ }
+ return err;
+}
+
+void exfat_chain_set(struct exfat_chain *ec, unsigned int dir,
+ unsigned int size, unsigned char flags)
+{
+ ec->dir = dir;
+ ec->size = size;
+ ec->flags = flags;
+}
+
+void exfat_chain_dup(struct exfat_chain *dup, struct exfat_chain *ec)
+{
+ return exfat_chain_set(dup, ec->dir, ec->size, ec->flags);
+}