On Sun, Aug 18, 2019 at 09:58:05AM -0700, Deepa Dinamani wrote:
Note that the min timestamp is assumed to be 01 Jan 1970 00:00:00 (Unix epoch). This is consistent with the way we convert timestamps in adfs_adfs2unix_time().
That's not actually correct. RISC OS timestamps are centiseconds since 1900 stored in 5 bytes.
Signed-off-by: Deepa Dinamani deepa.kernel@gmail.com
fs/adfs/adfs.h | 13 +++++++++++++ fs/adfs/inode.c | 8 ++------ fs/adfs/super.c | 2 ++ 3 files changed, 17 insertions(+), 6 deletions(-)
diff --git a/fs/adfs/adfs.h b/fs/adfs/adfs.h index b7e844d2f321..dca8b23aa43f 100644 --- a/fs/adfs/adfs.h +++ b/fs/adfs/adfs.h @@ -3,6 +3,19 @@ #include <linux/fs.h> #include <linux/adfs_fs.h> +/*
- 01 Jan 1970 00:00:00 (Unix epoch) as seconds since
- 01 Jan 1900 00:00:00 (RISC OS epoch)
- */
+#define RISC_OS_EPOCH_DELTA 2208988800LL
+/*
- Convert 40 bit centi seconds to seconds
- since 01 Jan 1900 00:00:00 (RISC OS epoch)
- The result is 2248-06-03 06:57:57 GMT
- */
+#define ADFS_MAX_TIMESTAMP ((0xFFFFFFFFFFLL / 100) - RISC_OS_EPOCH_DELTA)
/* Internal data structures for ADFS */ #define ADFS_FREE_FRAG 0 diff --git a/fs/adfs/inode.c b/fs/adfs/inode.c index 124de75413a5..41eca1c451dc 100644 --- a/fs/adfs/inode.c +++ b/fs/adfs/inode.c @@ -167,11 +167,7 @@ static void adfs_adfs2unix_time(struct timespec64 *tv, struct inode *inode) { unsigned int high, low;
- /* 01 Jan 1970 00:00:00 (Unix epoch) as nanoseconds since
* 01 Jan 1900 00:00:00 (RISC OS epoch)*/- static const s64 nsec_unix_epoch_diff_risc_os_epoch =
2208988800000000000LL;
- static const s64 nsec_unix_epoch_diff_risc_os_epoch = RISC_OS_EPOCH_DELTA * NSEC_PER_SEC; s64 nsec;
if (!adfs_inode_is_stamped(inode)) @@ -216,7 +212,7 @@ adfs_unix2adfs_time(struct inode *inode, unsigned int secs) if (adfs_inode_is_stamped(inode)) { /* convert 32-bit seconds to 40-bit centi-seconds */ low = (secs & 255) * 100;
high = (secs / 256) * 100 + (low >> 8) + 0x336e996a;
high = (secs / 256) * 100 + (low >> 8) + (RISC_OS_EPOCH_DELTA*100/256);ADFS_I(inode)->loadaddr = (high >> 24) | (ADFS_I(inode)->loadaddr & ~0xff); diff --git a/fs/adfs/super.c b/fs/adfs/super.c index 65b04ebb51c3..f074fe7d7158 100644 --- a/fs/adfs/super.c +++ b/fs/adfs/super.c @@ -463,6 +463,8 @@ static int adfs_fill_super(struct super_block *sb, void *data, int silent) asb->s_map_size = dr->nzones | (dr->nzones_high << 8); asb->s_map2blk = dr->log2bpmb - dr->log2secsize; asb->s_log2sharesize = dr->log2sharesize;
- sb->s_time_min = 0;
- sb->s_time_max = ADFS_MAX_TIMESTAMP;
asb->s_map = adfs_read_map(sb, dr); if (IS_ERR(asb->s_map)) { -- 2.17.1