From 4881c4971df04107b37c29bb6c719ec29ceb6571 Mon Sep 17 00:00:00 2001 From: Deepa Dinamani Date: Sun, 21 Jan 2018 18:04:24 -0800 Subject: ext4: Initialize timestamps limits ext4 has different overflow limits for max filesystem timestamps based on the extra bytes available. The timestamp limits are calculated according to the encoding table in a4dad1ae24f85i(ext4: Fix handling of extended tv_sec): * extra msb of adjust for signed * epoch 32-bit 32-bit tv_sec to * bits time decoded 64-bit tv_sec 64-bit tv_sec valid time range * 0 0 1 -0x80000000..-0x00000001 0x000000000 1901-12-13..1969-12-31 * 0 0 0 0x000000000..0x07fffffff 0x000000000 1970-01-01..2038-01-19 * 0 1 1 0x080000000..0x0ffffffff 0x100000000 2038-01-19..2106-02-07 * 0 1 0 0x100000000..0x17fffffff 0x100000000 2106-02-07..2174-02-25 * 1 0 1 0x180000000..0x1ffffffff 0x200000000 2174-02-25..2242-03-16 * 1 0 0 0x200000000..0x27fffffff 0x200000000 2242-03-16..2310-04-04 * 1 1 1 0x280000000..0x2ffffffff 0x300000000 2310-04-04..2378-04-22 * 1 1 0 0x300000000..0x37fffffff 0x300000000 2378-04-22..2446-05-10 Note that the time limits are not correct for deletion times. Added a warn when an inode cannot be extended to incorporate an extended timestamp. Signed-off-by: Deepa Dinamani Reviewed-by: Andreas Dilger Acked-by: Jeff Layton Cc: tytso@mit.edu Cc: adilger.kernel@dilger.ca Cc: linux-ext4@vger.kernel.org --- fs/ext4/ext4.h | 10 +++++++++- fs/ext4/super.c | 17 +++++++++++++++-- 2 files changed, 24 insertions(+), 3 deletions(-) (limited to 'fs/ext4') diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h index bf660aa7a9e0..9e3ae3be3de9 100644 --- a/fs/ext4/ext4.h +++ b/fs/ext4/ext4.h @@ -828,11 +828,15 @@ static inline void ext4_decode_extra_time(struct timespec64 *time, #define EXT4_INODE_SET_XTIME(xtime, inode, raw_inode) \ do { \ - (raw_inode)->xtime = cpu_to_le32((inode)->xtime.tv_sec); \ if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra)) {\ + (raw_inode)->xtime = cpu_to_le32((inode)->xtime.tv_sec); \ (raw_inode)->xtime ## _extra = \ ext4_encode_extra_time(&(inode)->xtime); \ } \ + else {\ + (raw_inode)->xtime = cpu_to_le32(clamp_t(int32_t, (inode)->xtime.tv_sec, S32_MIN, S32_MAX)); \ + ext4_warning_inode(inode, "inode does not support timestamps beyond 2038"); \ + } \ } while (0) #define EXT4_EINODE_SET_XTIME(xtime, einode, raw_inode) \ @@ -1632,6 +1636,10 @@ static inline void ext4_clear_state_flags(struct ext4_inode_info *ei) #define EXT4_GOOD_OLD_INODE_SIZE 128 +#define EXT4_EXTRA_TIMESTAMP_MAX (((s64)1 << 34) - 1 + S32_MIN) +#define EXT4_NON_EXTRA_TIMESTAMP_MAX S32_MAX +#define EXT4_TIMESTAMP_MIN S32_MIN + /* * Feature set definitions */ diff --git a/fs/ext4/super.c b/fs/ext4/super.c index 4079605d437a..3ea2d60f33aa 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -4035,8 +4035,21 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent) sbi->s_inode_size); goto failed_mount; } - if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE) - sb->s_time_gran = 1 << (EXT4_EPOCH_BITS - 2); + /* + * i_atime_extra is the last extra field available for [acm]times in + * struct ext4_inode. Checking for that field should suffice to ensure + * we have extra space for all three. + */ + if (sbi->s_inode_size >= offsetof(struct ext4_inode, i_atime_extra) + + sizeof(((struct ext4_inode *)0)->i_atime_extra)) { + sb->s_time_gran = 1; + sb->s_time_max = EXT4_EXTRA_TIMESTAMP_MAX; + } else { + sb->s_time_gran = NSEC_PER_SEC; + sb->s_time_max = EXT4_NON_EXTRA_TIMESTAMP_MAX; + } + + sb->s_time_min = EXT4_TIMESTAMP_MIN; } sbi->s_desc_size = le16_to_cpu(es->s_desc_size); -- cgit v1.2.3 From cba465b4f9820b0d929822a70341dde14909fc18 Mon Sep 17 00:00:00 2001 From: Deepa Dinamani Date: Wed, 4 Sep 2019 08:02:51 -0700 Subject: ext4: Reduce ext4 timestamp warnings When ext4 file systems were created intentionally with 128 byte inodes, the rate-limited warning of eventual possible timestamp overflow are still emitted rather frequently. Remove the warning for now. Discussion for whether any warning is needed, and where it should be emitted, can be found at https://lore.kernel.org/lkml/1567523922.5576.57.camel@lca.pw/. I can post a separate follow-up patch after the conclusion. Reported-by: Qian Cai Signed-off-by: Deepa Dinamani Reviewed-by: Andreas Dilger Signed-off-by: Arnd Bergmann --- fs/ext4/ext4.h | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) (limited to 'fs/ext4') diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h index 9e3ae3be3de9..24b14bd3feab 100644 --- a/fs/ext4/ext4.h +++ b/fs/ext4/ext4.h @@ -833,10 +833,8 @@ do { \ (raw_inode)->xtime ## _extra = \ ext4_encode_extra_time(&(inode)->xtime); \ } \ - else {\ + else \ (raw_inode)->xtime = cpu_to_le32(clamp_t(int32_t, (inode)->xtime.tv_sec, S32_MIN, S32_MAX)); \ - ext4_warning_inode(inode, "inode does not support timestamps beyond 2038"); \ - } \ } while (0) #define EXT4_EINODE_SET_XTIME(xtime, einode, raw_inode) \ -- cgit v1.2.3