Searched hist:"53 bb724f94f57b67213e08a4c155c8c5eb74c644" (Results 1 – 3 of 3) sorted by last modified time
| /linux/drivers/mtd/ |
| H A D | mtdchar.c | diff 53bb724f94f57b67213e08a4c155c8c5eb74c644 Mon Sep 21 22:26:59 CEST 2015 Brian Norris <computersforpeace@gmail.com> mtd: provide proper 32/64-bit compat_ioctl() support for BLKPG
After a bit of poking around wondering why my 32-bit user-space can't
seem to send a proper ioctl(BLKPG) to an MTD on my 64-bit kernel
(ARM64), I noticed that struct blkpg_ioctl_arg is actually pretty
unsuitable for use in the ioctl() ABI, due to its use of raw pointers,
and its lack of alignment/packing restrictions (32-bit arch'es tend to
pack the 4 fields into 4 32-bit words, whereas 64-bit arch'es would add
padding after the third int, and make this 6 32-bit words).
Anyway, this means BLKPG deserves some special compat_ioctl handling. Do
the conversion in a small shim for MTD.
block/compat_ioctl.c already has compat support for the block subsystem,
but it does so by a re-marshalling data to/from user-space (see
compat_blkpg_ioctl()). Personally, I think this approach is cleaner.
Tested only on MTD, with an ARM32 user space on an ARM64 kernel.
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
|
| /linux/include/uapi/linux/ |
| H A D | blkpg.h | diff 53bb724f94f57b67213e08a4c155c8c5eb74c644 Mon Sep 21 22:26:59 CEST 2015 Brian Norris <computersforpeace@gmail.com> mtd: provide proper 32/64-bit compat_ioctl() support for BLKPG
After a bit of poking around wondering why my 32-bit user-space can't
seem to send a proper ioctl(BLKPG) to an MTD on my 64-bit kernel
(ARM64), I noticed that struct blkpg_ioctl_arg is actually pretty
unsuitable for use in the ioctl() ABI, due to its use of raw pointers,
and its lack of alignment/packing restrictions (32-bit arch'es tend to
pack the 4 fields into 4 32-bit words, whereas 64-bit arch'es would add
padding after the third int, and make this 6 32-bit words).
Anyway, this means BLKPG deserves some special compat_ioctl handling. Do
the conversion in a small shim for MTD.
block/compat_ioctl.c already has compat support for the block subsystem,
but it does so by a re-marshalling data to/from user-space (see
compat_blkpg_ioctl()). Personally, I think this approach is cleaner.
Tested only on MTD, with an ARM32 user space on an ARM64 kernel.
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
|
| /linux/include/linux/ |
| H A D | blkpg.h | diff 53bb724f94f57b67213e08a4c155c8c5eb74c644 Mon Sep 21 22:26:59 CEST 2015 Brian Norris <computersforpeace@gmail.com> mtd: provide proper 32/64-bit compat_ioctl() support for BLKPG
After a bit of poking around wondering why my 32-bit user-space can't
seem to send a proper ioctl(BLKPG) to an MTD on my 64-bit kernel
(ARM64), I noticed that struct blkpg_ioctl_arg is actually pretty
unsuitable for use in the ioctl() ABI, due to its use of raw pointers,
and its lack of alignment/packing restrictions (32-bit arch'es tend to
pack the 4 fields into 4 32-bit words, whereas 64-bit arch'es would add
padding after the third int, and make this 6 32-bit words).
Anyway, this means BLKPG deserves some special compat_ioctl handling. Do
the conversion in a small shim for MTD.
block/compat_ioctl.c already has compat support for the block subsystem,
but it does so by a re-marshalling data to/from user-space (see
compat_blkpg_ioctl()). Personally, I think this approach is cleaner.
Tested only on MTD, with an ARM32 user space on an ARM64 kernel.
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
|