forked from Minki/linux
6ced9aa7b5
We exchange file timestamps with user space using psdev device read/write operations with a fixed but architecture specific binary layout. On 32-bit systems, this uses a 'timespec' structure that is defined by the C library to contain two 32-bit values for seconds and nanoseconds. As we get ready for the year 2038 overflow of the 32-bit signed seconds, the kernel now uses 64-bit timestamps internally, and user space will do the same change by changing the 'timespec' definition in the future. Unfortunately, this breaks the layout of the coda_vattr structure, so we need to redefine that in terms of something that does not change. I'm introducing a new 'struct vtimespec' structure here that keeps the existing layout, and the same change has to be done in the coda user space copy of linux/coda.h before anyone can use that on a 32-bit architecture with 64-bit time_t. An open question is what should happen to actual times past y2038, as they are now truncated to the last valid date when sent to user space, and interpreted as pre-1970 times when a timestamp with the MSB set is read back into the kernel. Alternatively, we could change the new timespec64_to_coda()/coda_to_timespec64() functions to use a different interpretation and extend the available range further to the future by disallowing past timestamps. This would require more changes in the user space side though. Link: http://lkml.kernel.org/r/562b7324149461743e4fbe2fedbf7c242f7e274a.1558117389.git.jaharkes@cs.cmu.edu Link: https://patchwork.kernel.org/patch/10474735/ Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Jan Harkes <jaharkes@cs.cmu.edu> Acked-by: Jan Harkes <jaharkes@cs.cmu.edu> Cc: Colin Ian King <colin.king@canonical.com> Cc: Dan Carpenter <dan.carpenter@oracle.com> Cc: David Howells <dhowells@redhat.com> Cc: Fabian Frederick <fabf@skynet.be> Cc: Mikko Rapeli <mikko.rapeli@iki.fi> Cc: Sam Protsenko <semen.protsenko@linaro.org> Cc: Yann Droneaud <ydroneaud@opteya.com> Cc: Zhouyang Jia <jiazhouyang09@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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cache.c | ||
cnode.c | ||
coda_cache.h | ||
coda_fs_i.h | ||
coda_int.h | ||
coda_linux.c | ||
coda_linux.h | ||
dir.c | ||
file.c | ||
inode.c | ||
Kconfig | ||
Makefile | ||
pioctl.c | ||
psdev.c | ||
symlink.c | ||
sysctl.c | ||
upcall.c |