AuxXxilium/linux_dsm_epyc7002
1
0
Fork 0
mirror of https://github.com/AuxXxilium/linux_dsm_epyc7002.git synced 2024-11-30 12:16:45 +07:00
Code Issues Actions Packages Projects Releases Wiki Activity
f27bd5bfed
linux_dsm_epyc7002/arch/m68k/include/asm/div64.h

36 lines
819 B
C
Raw Normal View History

m68k: merge the mmu and non-mmu versions of div64.h Trivial merge of the mmu and non-mmu versions of div64.h Signed-off-by: Greg Ungerer <gerg@uclinux.org> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
2009-02-06 11:50:08 +07:00
#ifndef _M68K_DIV64_H
#define _M68K_DIV64_H
m68k: handle presence of 64bit mul/div instructions cleanly The traditional 68000 processors and the newer reduced instruction set ColdFire processors do not support the 32*32->64 multiply or the 64/32->32 divide instructions. This is not a difference based on the presence of a hardware MMU or not. Create a new config symbol to mark that a CPU type doesn't support the longer multiply/divide instructions. Use this then as a basis for using the fast 64bit based divide (in div64.h) and for linking in the extra libgcc functions that may be required (mulsi3, divsi3, etc). Signed-off-by: Greg Ungerer <gerg@uclinux.org> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
2011-11-11 12:13:08 +07:00
#ifdef CONFIG_CPU_HAS_NO_MULDIV64
#include <asm-generic/div64.h>
#else
m68k: merge the mmu and non-mmu versions of div64.h Trivial merge of the mmu and non-mmu versions of div64.h Signed-off-by: Greg Ungerer <gerg@uclinux.org> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
2009-02-06 11:50:08 +07:00
#include <linux/types.h>
/* n = n / base; return rem; */
#define do_div(n, base) ({ \
union { \
unsigned long n32[2]; \
unsigned long long n64; \
} __n; \
unsigned long __rem, __upper; \
m68k: Truncate base in do_div() Explicitly truncate the second operand of do_div() to 32 bits to guard against bogus code calling it with a 64-bit divisor. [Thorsten] After upgrading from 3.2 to 3.10, mounting a btrfs volume fails with: btrfs: setting nodatacow, compression disabled btrfs: enabling auto recovery btrfs: disk space caching is enabled *** ZERO DIVIDE *** FORMAT=2 Current process id is 722 BAD KERNEL TRAP: 00000000 Modules linked in: evdev mac_hid ext4 crc16 jbd2 mbcache btrfs xor lzo_compress zlib_deflate raid6_pq crc32c libcrc32c PC: [<319535b2>] __btrfs_map_block+0x11c/0x119a [btrfs] SR: 2000 SP: 30c1fab4 a2: 30f0faf0 d0: 00000000 d1: 00001000 d2: 00000000 d3: 00000000 d4: 00010000 d5: 00000000 a0: 3085c72c a1: 3085c72c Process mount (pid: 722, task=30f0faf0) Frame format=2 instr addr=319535ae Stack from 30c1faec: 00000000 00000020 00000000 00001000 00000000 01401000 30253928 300ffc00 00a843ac 3026f640 00000000 00010000 0009e250 00d106c0 00011220 00000000 00001000 301c6830 0009e32a 000000ff 00000009 3085c72c 00000000 00000000 30c1fd14 00000000 00000020 00000000 30c1fd14 0009e26c 00000020 00000003 00000000 0009dd8a 300b0b6c 30253928 00a843ac 00001000 00000000 00000000 0000a008 3194e76a 30253928 00a843ac 00001000 00000000 00000000 00000002 Call Trace: [<00001000>] kernel_pg_dir+0x0/0x1000 [...] Code: 222e ff74 2a2e ff5c 2c2e ff60 4c45 1402 <2d40> ff64 2d41 ff68 2205 4c2e 1800 ff68 4c04 0800 2041 d1c0 2206 4c2e 1400 ff68 [Geert] As diagnosed by Andreas, fs/btrfs/volumes.c:__btrfs_map_block() calls do_div(stripe_nr, stripe_len); with stripe_len u64, while do_div() assumes the divisor is a 32-bit number. Due to the lack of truncation in the m68k-specific implementation of do_div(), the division is performed using the upper 32-bit word of stripe_len, which is zero. This was introduced by commit 53b381b3abeb86f12787a6c40fee9b2f71edc23b ("Btrfs: RAID5 and RAID6"), which changed the divisor from map->stripe_len (struct map_lookup.stripe_len is int) to a 64-bit temporary. Reported-by: Thorsten Glaser <tg@debian.org> Signed-off-by: Andreas Schwab <schwab@linux-m68k.org> Tested-by: Thorsten Glaser <tg@debian.org> Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Cc: stable@vger.kernel.org
2013-08-09 20:14:08 +07:00
unsigned long __base = (base); \
m68k: merge the mmu and non-mmu versions of div64.h Trivial merge of the mmu and non-mmu versions of div64.h Signed-off-by: Greg Ungerer <gerg@uclinux.org> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
2009-02-06 11:50:08 +07:00
\
__n.n64 = (n); \
if ((__upper = __n.n32[0])) { \
asm ("divul.l %2,%1:%0" \
m68k: Truncate base in do_div() Explicitly truncate the second operand of do_div() to 32 bits to guard against bogus code calling it with a 64-bit divisor. [Thorsten] After upgrading from 3.2 to 3.10, mounting a btrfs volume fails with: btrfs: setting nodatacow, compression disabled btrfs: enabling auto recovery btrfs: disk space caching is enabled *** ZERO DIVIDE *** FORMAT=2 Current process id is 722 BAD KERNEL TRAP: 00000000 Modules linked in: evdev mac_hid ext4 crc16 jbd2 mbcache btrfs xor lzo_compress zlib_deflate raid6_pq crc32c libcrc32c PC: [<319535b2>] __btrfs_map_block+0x11c/0x119a [btrfs] SR: 2000 SP: 30c1fab4 a2: 30f0faf0 d0: 00000000 d1: 00001000 d2: 00000000 d3: 00000000 d4: 00010000 d5: 00000000 a0: 3085c72c a1: 3085c72c Process mount (pid: 722, task=30f0faf0) Frame format=2 instr addr=319535ae Stack from 30c1faec: 00000000 00000020 00000000 00001000 00000000 01401000 30253928 300ffc00 00a843ac 3026f640 00000000 00010000 0009e250 00d106c0 00011220 00000000 00001000 301c6830 0009e32a 000000ff 00000009 3085c72c 00000000 00000000 30c1fd14 00000000 00000020 00000000 30c1fd14 0009e26c 00000020 00000003 00000000 0009dd8a 300b0b6c 30253928 00a843ac 00001000 00000000 00000000 0000a008 3194e76a 30253928 00a843ac 00001000 00000000 00000000 00000002 Call Trace: [<00001000>] kernel_pg_dir+0x0/0x1000 [...] Code: 222e ff74 2a2e ff5c 2c2e ff60 4c45 1402 <2d40> ff64 2d41 ff68 2205 4c2e 1800 ff68 4c04 0800 2041 d1c0 2206 4c2e 1400 ff68 [Geert] As diagnosed by Andreas, fs/btrfs/volumes.c:__btrfs_map_block() calls do_div(stripe_nr, stripe_len); with stripe_len u64, while do_div() assumes the divisor is a 32-bit number. Due to the lack of truncation in the m68k-specific implementation of do_div(), the division is performed using the upper 32-bit word of stripe_len, which is zero. This was introduced by commit 53b381b3abeb86f12787a6c40fee9b2f71edc23b ("Btrfs: RAID5 and RAID6"), which changed the divisor from map->stripe_len (struct map_lookup.stripe_len is int) to a 64-bit temporary. Reported-by: Thorsten Glaser <tg@debian.org> Signed-off-by: Andreas Schwab <schwab@linux-m68k.org> Tested-by: Thorsten Glaser <tg@debian.org> Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Cc: stable@vger.kernel.org
2013-08-09 20:14:08 +07:00
: "=d" (__n.n32[0]), "=d" (__upper) \
: "d" (__base), "0" (__n.n32[0])); \
m68k: merge the mmu and non-mmu versions of div64.h Trivial merge of the mmu and non-mmu versions of div64.h Signed-off-by: Greg Ungerer <gerg@uclinux.org> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
2009-02-06 11:50:08 +07:00
} \
asm ("divu.l %2,%1:%0" \
m68k: Truncate base in do_div() Explicitly truncate the second operand of do_div() to 32 bits to guard against bogus code calling it with a 64-bit divisor. [Thorsten] After upgrading from 3.2 to 3.10, mounting a btrfs volume fails with: btrfs: setting nodatacow, compression disabled btrfs: enabling auto recovery btrfs: disk space caching is enabled *** ZERO DIVIDE *** FORMAT=2 Current process id is 722 BAD KERNEL TRAP: 00000000 Modules linked in: evdev mac_hid ext4 crc16 jbd2 mbcache btrfs xor lzo_compress zlib_deflate raid6_pq crc32c libcrc32c PC: [<319535b2>] __btrfs_map_block+0x11c/0x119a [btrfs] SR: 2000 SP: 30c1fab4 a2: 30f0faf0 d0: 00000000 d1: 00001000 d2: 00000000 d3: 00000000 d4: 00010000 d5: 00000000 a0: 3085c72c a1: 3085c72c Process mount (pid: 722, task=30f0faf0) Frame format=2 instr addr=319535ae Stack from 30c1faec: 00000000 00000020 00000000 00001000 00000000 01401000 30253928 300ffc00 00a843ac 3026f640 00000000 00010000 0009e250 00d106c0 00011220 00000000 00001000 301c6830 0009e32a 000000ff 00000009 3085c72c 00000000 00000000 30c1fd14 00000000 00000020 00000000 30c1fd14 0009e26c 00000020 00000003 00000000 0009dd8a 300b0b6c 30253928 00a843ac 00001000 00000000 00000000 0000a008 3194e76a 30253928 00a843ac 00001000 00000000 00000000 00000002 Call Trace: [<00001000>] kernel_pg_dir+0x0/0x1000 [...] Code: 222e ff74 2a2e ff5c 2c2e ff60 4c45 1402 <2d40> ff64 2d41 ff68 2205 4c2e 1800 ff68 4c04 0800 2041 d1c0 2206 4c2e 1400 ff68 [Geert] As diagnosed by Andreas, fs/btrfs/volumes.c:__btrfs_map_block() calls do_div(stripe_nr, stripe_len); with stripe_len u64, while do_div() assumes the divisor is a 32-bit number. Due to the lack of truncation in the m68k-specific implementation of do_div(), the division is performed using the upper 32-bit word of stripe_len, which is zero. This was introduced by commit 53b381b3abeb86f12787a6c40fee9b2f71edc23b ("Btrfs: RAID5 and RAID6"), which changed the divisor from map->stripe_len (struct map_lookup.stripe_len is int) to a 64-bit temporary. Reported-by: Thorsten Glaser <tg@debian.org> Signed-off-by: Andreas Schwab <schwab@linux-m68k.org> Tested-by: Thorsten Glaser <tg@debian.org> Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Cc: stable@vger.kernel.org
2013-08-09 20:14:08 +07:00
: "=d" (__n.n32[1]), "=d" (__rem) \
: "d" (__base), "1" (__upper), "0" (__n.n32[1])); \
m68k: merge the mmu and non-mmu versions of div64.h Trivial merge of the mmu and non-mmu versions of div64.h Signed-off-by: Greg Ungerer <gerg@uclinux.org> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
2009-02-06 11:50:08 +07:00
(n) = __n.n64; \
__rem; \
})
m68k: handle presence of 64bit mul/div instructions cleanly The traditional 68000 processors and the newer reduced instruction set ColdFire processors do not support the 32*32->64 multiply or the 64/32->32 divide instructions. This is not a difference based on the presence of a hardware MMU or not. Create a new config symbol to mark that a CPU type doesn't support the longer multiply/divide instructions. Use this then as a basis for using the fast 64bit based divide (in div64.h) and for linking in the extra libgcc functions that may be required (mulsi3, divsi3, etc). Signed-off-by: Greg Ungerer <gerg@uclinux.org> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
2011-11-11 12:13:08 +07:00
#endif /* CONFIG_CPU_HAS_NO_MULDIV64 */
m68k: merge the mmu and non-mmu versions of div64.h Trivial merge of the mmu and non-mmu versions of div64.h Signed-off-by: Greg Ungerer <gerg@uclinux.org> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
2009-02-06 11:50:08 +07:00
#endif /* _M68K_DIV64_H */
Reference in New Issue Copy Permalink