Commit 9d14545b authored by Arnd Bergmann's avatar Arnd Bergmann
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Merge branch 'limits' of https://github.com/deepa-hub/vfs into y2038 

The series is an update and a more complete version of the
previously posted series at
https://lore.kernel.org/linux-fsdevel/20180122020426.2988-1-deepa.kernel@gmail.com/

Thanks to Arnd Bergmann for doing a few preliminary reviews.
They helped me fix a few issues I had overlooked.

The limits (sometimes granularity also) for the filesystems updated here are according to the
following table:

File system   Time type                      Start year Expiration year Granularity
cramfs        fixed                          0          0
romfs         fixed                          0          0
pstore        ascii seconds (27 digit ascii) S64_MIN    S64_MAX         1
coda          INT64                          S64_MIN    S64_MAX         1
omfs          64-bit milliseconds            0          U64_MAX/ 1000   NSEC_PER_MSEC
befs          unsigned 48-bit seconds        0          0xffffffffffff  alloc_super
bfs           unsigned 32-bit seconds        0          U32_MAX         alloc_super
efs           unsigned 32-bit seconds        0          U32_MAX         alloc_super
ext2          signed 32-bit seconds          S32_MIN    S32_MAX         alloc_super
ext3          signed 32-bit seconds          S32_MIN    S32_MAX         alloc_super
ext4 (old)    signed 32-bit seconds          S32_MIN    S32_MAX         alloc_super
ext4 (extra)  34-bit seconds, 30-bit ns      S32_MIN    0x37fffffff     1
freevxfs      u32 secs/usecs                 0          U32_MAX         alloc_super
jffs2         unsigned 32-bit seconds        0          U32_MAX         alloc_super
jfs           unsigned 32-bit seconds/ns     0          U32_MAX         1
minix         unsigned 32-bit seconds        0          U32_MAX         alloc_super
qnx4          unsigned 32-bit seconds        0          U32_MAX         alloc_super
qnx6          unsigned 32-bit seconds        0          U32_MAX         alloc_super
reiserfs      unsigned 32-bit seconds        0          U32_MAX         alloc_super
squashfs      unsigned 32-bit seconds        0          U32_MAX         alloc_super
ufs1          signed 32-bit seconds          S32_MIN    S32_MAX         NSEC_PER_SEC
ufs2          signed 64-bit seconds/u32 ns   S64_MIN    S64_MAX         1
xfs           signed 32-bit seconds/ns       S32_MIN    S32_MAX         1
ceph          unsigned 32-bit second/ns      0          U32_MAX         1000
sysv          unsigned 32-bit seconds        0          U32_MAX         alloc_super
affs          u32 day, min, ticks            1978       u32_max days    NSEC_PER_SEC
nfsv2         unsigned 32-bit seconds/ns     0          U32_MAX         1
nfsv3         unsigned 32-bit seconds/ns     0          U32_MAX         1000
nfsv4         u64 seconds/u32 ns             S64_MIN    S64_MAX         1000
isofs         u8 year since 1900 (fixable)   1900       2155            alloc_super
hpfs          unsigned 32-bit seconds        1970       2106            alloc_super
fat           7-bit years, 2s resolution     1980       2107
cifs (smb)    7-bit years                    1980       2107
cifs (modern) 64-bit 100ns since 1601        1601       30828
9p (9P2000)   unsigned 32-bit seconds        1970       2106
9p (9P2000.L) signed 64-bit seconds, ns      1970       S64_MAX

Granularity column filled in by the alloc_super() in the above table indicates that
the granularity is NSEC_PER_SEC.
Note that anything not mentioned above still has the default limits
S64_MIN..S64_MAX.

The patches in the series are as structured below:
1. Add vfs support to maintain the limits per filesystem.
2. Add a new timestamp_truncate() api for clamping timestamps
   according to the filesystem limits.
3. Add a warning for mount syscall to indicate the impending
   expiry of timestamps.
4. Modify utimes to clamp the timestamps.
5. Fill in limits for filesystems.

A test for checking file system timestamp limits has been posted
at https://www.spinics.net/lists/fstests/msg12262.html

Changes since v8:
* Dropped orangefs patch because of ongoing discussion
* Dropped adfs patch because a conflict with Russell's ADFS series
Changes since v7:
* Dropped fat modifications from timespec_truncate patch
* Leverage timestamp_truncate function in utimes
* Added a fix for pstore ramoops timestamps
* Added ext4 warning for inodes without room for extended timestamps.
* Made mount warning more human readable
Changes since v6:
* No change in mount behavior because of expiry of timestamps.
* Included limits for more filesystems.
Changes since v5:
* Dropped y2038-specific changes
Changes since v4:
* Added documentation for boot param
Changes since v3:
* Remove redundant initializations in libfs.c
* Change early_param to __setup similar to other root mount options.
* Fix documentation warning
Changes since v2:
* Introduce early boot param override for checks.
* Drop afs patch for timestamp limits.
Changes since v1:
* return EROFS on mount errors
* fix mtime copy/paste error in utimes

* 'limits' of https://github.com/deepa-hub/vfs:
  isofs: Initialize filesystem timestamp ranges
  pstore: fs superblock limits
  fs: omfs: Initialize filesystem timestamp ranges
  fs: hpfs: Initialize filesystem timestamp ranges
  fs: ceph: Initialize filesystem timestamp ranges
  fs: sysv: Initialize filesystem timestamp ranges
  fs: affs: Initialize filesystem timestamp ranges
  fs: fat: Initialize filesystem timestamp ranges
  fs: cifs: Initialize filesystem timestamp ranges
  fs: nfs: Initialize filesystem timestamp ranges
  ext4: Initialize timestamps limits
  9p: Fill min and max timestamps in sb
  fs: Fill in max and min timestamps in superblock
  utimes: Clamp the timestamps before update
  mount: Add mount warning for impending timestamp expiry
  timestamp_truncate: Replace users of timespec64_trunc
  vfs: Add timestamp_truncate() api
  vfs: Add file timestamp range support

Link: https://lore.kernel.org/lkml/20190730014924.2193-1-deepa.kernel@gmail.com/
Link: https://lore.kernel.org/lkml/20190830154744.4868-1-deepa.kernel@gmail.com/


Signed-off-by: default avatarArnd Bergmann <arnd@arndb.de>
parents a55aa89a 5ad32b3a

fs/9p/vfs_super.c

+5 −1
Original line number Diff line number Diff line
@@ -69,8 +69,12 @@ v9fs_fill_super(struct super_block *sb, struct v9fs_session_info *v9ses, 
	if (v9fs_proto_dotl(v9ses)) {

		sb->s_op = &v9fs_super_ops_dotl;

		sb->s_xattr = v9fs_xattr_handlers;

	} else

	} else {

		sb->s_op = &v9fs_super_ops;

		sb->s_time_max = U32_MAX;

	}



	sb->s_time_min = 0;



	ret = super_setup_bdi(sb);

	if (ret)

fs/affs/amigaffs.c

+1 −1
Original line number Diff line number Diff line
@@ -375,7 +375,7 @@ affs_secs_to_datestamp(time64_t secs, struct affs_date *ds) 
	u32	 minute;

	s32	 rem;



	secs -= sys_tz.tz_minuteswest * 60 + ((8 * 365 + 2) * 24 * 60 * 60);

	secs -= sys_tz.tz_minuteswest * 60 + AFFS_EPOCH_DELTA;

	if (secs < 0)

		secs = 0;

	days    = div_s64_rem(secs, 86400, &rem);

fs/affs/amigaffs.h

+3 −0
Original line number Diff line number Diff line
@@ -32,6 +32,9 @@ 


#define AFFS_ROOT_BMAPS		25



/* Seconds since Amiga epoch of 1978/01/01 to UNIX */

#define AFFS_EPOCH_DELTA ((8 * 365 + 2) * 86400LL)



struct affs_date {

	__be32 days;

	__be32 mins;

fs/affs/inode.c

+2 −2
Original line number Diff line number Diff line
@@ -150,10 +150,10 @@ struct inode *affs_iget(struct super_block *sb, unsigned long ino) 
	}



	inode->i_mtime.tv_sec = inode->i_atime.tv_sec = inode->i_ctime.tv_sec

		       = (be32_to_cpu(tail->change.days) * (24 * 60 * 60) +

		       = (be32_to_cpu(tail->change.days) * 86400LL +

		         be32_to_cpu(tail->change.mins) * 60 +

			 be32_to_cpu(tail->change.ticks) / 50 +

			 ((8 * 365 + 2) * 24 * 60 * 60)) +

			 AFFS_EPOCH_DELTA) +

			 sys_tz.tz_minuteswest * 60;

	inode->i_mtime.tv_nsec = inode->i_ctime.tv_nsec = inode->i_atime.tv_nsec = 0;

	affs_brelse(bh);

fs/affs/super.c

+4 −0
Original line number Diff line number Diff line
@@ -355,6 +355,10 @@ static int affs_fill_super(struct super_block *sb, void *data, int silent) 
	sb->s_op                = &affs_sops;

	sb->s_flags |= SB_NODIRATIME;



	sb->s_time_gran = NSEC_PER_SEC;

	sb->s_time_min = sys_tz.tz_minuteswest * 60 + AFFS_EPOCH_DELTA;

	sb->s_time_max = 86400LL * U32_MAX + 86400 + sb->s_time_min;



	sbi = kzalloc(sizeof(struct affs_sb_info), GFP_KERNEL);

	if (!sbi)

		return -ENOMEM;

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