From: Steven Rostedt <[email protected]> At Linux Plumbers, Andy Lutomirski approached me and pointed out that the function call syscall_get_arguments() implemented in x86 was horribly written and not optimized for the standard case of passing in 0 and 6 for the starting index and the number of system calls to get. When looking at all the users of this function, I discovered that all instances pass in only 0 and 6 for these arguments. Instead of having this function handle different cases that are never used, simply rewrite it to return the first 6 arguments of a system call.
This should help out the performance of tracing system calls by ptrace, ftrace and perf. Reported-by: Andy Lutomirski <[email protected]> Signed-off-by: Steven Rostedt <[email protected]> --- arch/arc/include/asm/syscall.h | 7 ++-- arch/arm/include/asm/syscall.h | 23 ++--------- arch/arm64/include/asm/syscall.h | 22 ++--------- arch/blackfin/include/asm/syscall.h | 22 +++++++---- arch/c6x/include/asm/syscall.h | 41 ++++---------------- arch/frv/include/asm/syscall.h | 26 +++---------- arch/h8300/include/asm/syscall.h | 34 ++++------------- arch/hexagon/include/asm/syscall.h | 4 +- arch/ia64/include/asm/syscall.h | 5 +-- arch/metag/include/asm/syscall.h | 4 +- arch/microblaze/include/asm/syscall.h | 4 +- arch/mips/include/asm/syscall.h | 3 +- arch/mn10300/include/asm/syscall.h | 32 +++------------- arch/nios2/include/asm/syscall.h | 42 ++++---------------- arch/openrisc/include/asm/syscall.h | 6 +-- arch/parisc/include/asm/syscall.h | 30 ++++----------- arch/powerpc/include/asm/syscall.h | 8 ++-- arch/s390/include/asm/syscall.h | 11 +++--- arch/sh/include/asm/syscall_32.h | 26 +++---------- arch/sh/include/asm/syscall_64.h | 4 +- arch/sparc/include/asm/syscall.h | 4 +- arch/tile/include/asm/syscall.h | 4 +- arch/um/include/asm/syscall-generic.h | 39 +++---------------- arch/x86/include/asm/syscall.h | 72 ++++++++--------------------------- include/asm-generic/syscall.h | 11 ++---- include/trace/events/syscalls.h | 2 +- kernel/seccomp.c | 2 +- kernel/trace/trace_syscalls.c | 4 +- lib/syscall.c | 2 +- 29 files changed, 124 insertions(+), 370 deletions(-) diff --git a/arch/arc/include/asm/syscall.h b/arch/arc/include/asm/syscall.h index 29de09804306..c7a4201ed62b 100644 --- a/arch/arc/include/asm/syscall.h +++ b/arch/arc/include/asm/syscall.h @@ -55,12 +55,11 @@ syscall_set_return_value(struct task_struct *task, struct pt_regs *regs, */ static inline void syscall_get_arguments(struct task_struct *task, struct pt_regs *regs, - unsigned int i, unsigned int n, unsigned long *args) + unsigned long *args) { unsigned long *inside_ptregs = &(regs->r0); - inside_ptregs -= i; - - BUG_ON((i + n) > 6); + unsigned int n = 6; + unsigned int i = 0; while (n--) { args[i++] = (*inside_ptregs); diff --git a/arch/arm/include/asm/syscall.h b/arch/arm/include/asm/syscall.h index e86c985b8c7a..1521b465b581 100644 --- a/arch/arm/include/asm/syscall.h +++ b/arch/arm/include/asm/syscall.h @@ -54,29 +54,14 @@ static inline void syscall_set_return_value(struct task_struct *task, static inline void syscall_get_arguments(struct task_struct *task, struct pt_regs *regs, - unsigned int i, unsigned int n, unsigned long *args) { - if (n == 0) - return; - - if (i + n > SYSCALL_MAX_ARGS) { - unsigned long *args_bad = args + SYSCALL_MAX_ARGS - i; - unsigned int n_bad = n + i - SYSCALL_MAX_ARGS; - pr_warn("%s called with max args %d, handling only %d\n", - __func__, i + n, SYSCALL_MAX_ARGS); - memset(args_bad, 0, n_bad * sizeof(args[0])); - n = SYSCALL_MAX_ARGS - i; - } + unsigned int n; - if (i == 0) { - args[0] = regs->ARM_ORIG_r0; - args++; - i++; - n--; - } + args[0] = regs->ARM_ORIG_r0; + args++; - memcpy(args, ®s->ARM_r0 + i, n * sizeof(args[0])); + memcpy(args, ®s->ARM_r0 + 1, 5 * sizeof(args[0])); } static inline void syscall_set_arguments(struct task_struct *task, diff --git a/arch/arm64/include/asm/syscall.h b/arch/arm64/include/asm/syscall.h index 709a574468f0..fb6668df435b 100644 --- a/arch/arm64/include/asm/syscall.h +++ b/arch/arm64/include/asm/syscall.h @@ -59,28 +59,12 @@ static inline void syscall_set_return_value(struct task_struct *task, static inline void syscall_get_arguments(struct task_struct *task, struct pt_regs *regs, - unsigned int i, unsigned int n, unsigned long *args) { - if (n == 0) - return; - - if (i + n > SYSCALL_MAX_ARGS) { - unsigned long *args_bad = args + SYSCALL_MAX_ARGS - i; - unsigned int n_bad = n + i - SYSCALL_MAX_ARGS; - pr_warning("%s called with max args %d, handling only %d\n", - __func__, i + n, SYSCALL_MAX_ARGS); - memset(args_bad, 0, n_bad * sizeof(args[0])); - } - - if (i == 0) { - args[0] = regs->orig_x0; - args++; - i++; - n--; - } + args[0] = regs->orig_x0; + args++; - memcpy(args, ®s->regs[i], n * sizeof(args[0])); + memcpy(args, ®s->regs[1], 5 * sizeof(args[0])); } static inline void syscall_set_arguments(struct task_struct *task, diff --git a/arch/blackfin/include/asm/syscall.h b/arch/blackfin/include/asm/syscall.h index 4921a4815cce..cef32063f54b 100644 --- a/arch/blackfin/include/asm/syscall.h +++ b/arch/blackfin/include/asm/syscall.h @@ -57,30 +57,36 @@ syscall_set_return_value(struct task_struct *task, struct pt_regs *regs, * syscall_get_arguments() * @task: unused * @regs: the register layout to extract syscall arguments from - * @i: first syscall argument to extract - * @n: number of syscall arguments to extract * @args: array to return the syscall arguments in * - * args[0] gets i'th argument, args[n - 1] gets the i+n-1'th argument + * Gets the 6 arguments of the system call */ static inline void syscall_get_arguments(struct task_struct *task, struct pt_regs *regs, - unsigned int i, unsigned int n, unsigned long *args) + unsigned long *args) { /* * Assume the ptrace layout doesn't change -- r5 is first in memory, * then r4, ..., then r0. So we simply reverse the ptrace register * array in memory to store into the args array. */ - long *aregs = ®s->r0 - i; - - BUG_ON(i > 5 || i + n > 6); + long *aregs = ®s->r0; + unsigned int n = 6; while (n--) *args++ = *aregs--; } -/* See syscall_get_arguments() comments */ +/** + * syscall_set_arguments() + * @task: unused + * @regs: the register layout to extract syscall arguments from + * @i: first syscall argument to extract + * @n: number of syscall arguments to extract + * @args: array to return the syscall arguments in + * + * args[0] gets i'th argument, args[n - 1] gets the i+n-1'th argument + */ static inline void syscall_set_arguments(struct task_struct *task, struct pt_regs *regs, unsigned int i, unsigned int n, const unsigned long *args) diff --git a/arch/c6x/include/asm/syscall.h b/arch/c6x/include/asm/syscall.h index ae2be315ee9c..06db3251926b 100644 --- a/arch/c6x/include/asm/syscall.h +++ b/arch/c6x/include/asm/syscall.h @@ -46,40 +46,15 @@ static inline void syscall_set_return_value(struct task_struct *task, } static inline void syscall_get_arguments(struct task_struct *task, - struct pt_regs *regs, unsigned int i, - unsigned int n, unsigned long *args) + struct pt_regs *regs, + unsigned long *args) { - switch (i) { - case 0: - if (!n--) - break; - *args++ = regs->a4; - case 1: - if (!n--) - break; - *args++ = regs->b4; - case 2: - if (!n--) - break; - *args++ = regs->a6; - case 3: - if (!n--) - break; - *args++ = regs->b6; - case 4: - if (!n--) - break; - *args++ = regs->a8; - case 5: - if (!n--) - break; - *args++ = regs->b8; - case 6: - if (!n--) - break; - default: - BUG(); - } + *args++ = regs->a4; + *args++ = regs->b4; + *args++ = regs->a6; + *args++ = regs->b6; + *args++ = regs->a8; + *args = regs->b8; } static inline void syscall_set_arguments(struct task_struct *task, diff --git a/arch/frv/include/asm/syscall.h b/arch/frv/include/asm/syscall.h index 70689eb29b98..4778fa399f52 100644 --- a/arch/frv/include/asm/syscall.h +++ b/arch/frv/include/asm/syscall.h @@ -71,29 +71,15 @@ static inline void syscall_set_return_value(struct task_struct *task, */ static inline void syscall_get_arguments(struct task_struct *task, struct pt_regs *regs, - unsigned int i, unsigned int n, unsigned long *args) { - /* - * Do this simply for now. If we need to start supporting - * fetching arguments from arbitrary indices, this will need some - * extra logic. Presently there are no in-tree users that depend - * on this behaviour. - */ - BUG_ON(i); - /* Argument pattern is: GR8, GR9, GR10, GR11, GR12, GR13 */ - switch (n) { - case 6: args[5] = regs->gr13; - case 5: args[4] = regs->gr12; - case 4: args[3] = regs->gr11; - case 3: args[2] = regs->gr10; - case 2: args[1] = regs->gr9; - case 1: args[0] = regs->gr8; - break; - default: - BUG(); - } + args[5] = regs->gr13; + args[4] = regs->gr12; + args[3] = regs->gr11; + args[2] = regs->gr10; + args[1] = regs->gr9; + args[0] = regs->gr8; } /* diff --git a/arch/h8300/include/asm/syscall.h b/arch/h8300/include/asm/syscall.h index b41f688d02cf..c0bb2e4c152f 100644 --- a/arch/h8300/include/asm/syscall.h +++ b/arch/h8300/include/asm/syscall.h @@ -16,34 +16,14 @@ syscall_get_nr(struct task_struct *task, struct pt_regs *regs) static inline void syscall_get_arguments(struct task_struct *task, struct pt_regs *regs, - unsigned int i, unsigned int n, unsigned long *args) + unsigned long *args) { - BUG_ON(i + n > 6); - - while (n > 0) { - switch (i) { - case 0: - *args++ = regs->er1; - break; - case 1: - *args++ = regs->er2; - break; - case 2: - *args++ = regs->er3; - break; - case 3: - *args++ = regs->er4; - break; - case 4: - *args++ = regs->er5; - break; - case 5: - *args++ = regs->er6; - break; - } - i++; - n--; - } + *args++ = regs->er1; + *args++ = regs->er2; + *args++ = regs->er3; + *args++ = regs->er4; + *args++ = regs->er5; + *args = regs->er6; } diff --git a/arch/hexagon/include/asm/syscall.h b/arch/hexagon/include/asm/syscall.h index 4af9c7b6f13a..ae3a1e24fabd 100644 --- a/arch/hexagon/include/asm/syscall.h +++ b/arch/hexagon/include/asm/syscall.h @@ -37,10 +37,8 @@ static inline long syscall_get_nr(struct task_struct *task, static inline void syscall_get_arguments(struct task_struct *task, struct pt_regs *regs, - unsigned int i, unsigned int n, unsigned long *args) { - BUG_ON(i + n > 6); - memcpy(args, &(®s->r00)[i], n * sizeof(args[0])); + memcpy(args, &(®s->r00)[0], 6 * sizeof(args[0])); } #endif diff --git a/arch/ia64/include/asm/syscall.h b/arch/ia64/include/asm/syscall.h index 1d0b875fec44..8204c1ff70ce 100644 --- a/arch/ia64/include/asm/syscall.h +++ b/arch/ia64/include/asm/syscall.h @@ -63,12 +63,9 @@ extern void ia64_syscall_get_set_arguments(struct task_struct *task, unsigned long *args, int rw); static inline void syscall_get_arguments(struct task_struct *task, struct pt_regs *regs, - unsigned int i, unsigned int n, unsigned long *args) { - BUG_ON(i + n > 6); - - ia64_syscall_get_set_arguments(task, regs, i, n, args, 0); + ia64_syscall_get_set_arguments(task, regs, 0, 6, args, 0); } static inline void syscall_set_arguments(struct task_struct *task, diff --git a/arch/metag/include/asm/syscall.h b/arch/metag/include/asm/syscall.h index 24fc97939f77..981bf74c2ec5 100644 --- a/arch/metag/include/asm/syscall.h +++ b/arch/metag/include/asm/syscall.h @@ -66,13 +66,11 @@ static inline void syscall_set_return_value(struct task_struct *task, static inline void syscall_get_arguments(struct task_struct *task, struct pt_regs *regs, - unsigned int i, unsigned int n, unsigned long *args) { unsigned int reg, j; - BUG_ON(i + n > 6); - for (j = i, reg = 6 - i; j < (i + n); j++, reg--) { + for (j = 0, reg = 6; j < 6; j++, reg--) { if (reg % 2) args[j] = regs->ctx.DX[(reg + 1) / 2].U0; else diff --git a/arch/microblaze/include/asm/syscall.h b/arch/microblaze/include/asm/syscall.h index 04a5bece8168..ec2b0be2076e 100644 --- a/arch/microblaze/include/asm/syscall.h +++ b/arch/microblaze/include/asm/syscall.h @@ -81,9 +81,11 @@ static inline void microblaze_set_syscall_arg(struct pt_regs *regs, static inline void syscall_get_arguments(struct task_struct *task, struct pt_regs *regs, - unsigned int i, unsigned int n, unsigned long *args) { + unsigned int i = 0; + unsigned int n = 6; + while (n--) *args++ = microblaze_get_syscall_arg(regs, i++); } diff --git a/arch/mips/include/asm/syscall.h b/arch/mips/include/asm/syscall.h index d87882513ee3..279878f58191 100644 --- a/arch/mips/include/asm/syscall.h +++ b/arch/mips/include/asm/syscall.h @@ -94,9 +94,10 @@ static inline void syscall_set_return_value(struct task_struct *task, static inline void syscall_get_arguments(struct task_struct *task, struct pt_regs *regs, - unsigned int i, unsigned int n, unsigned long *args) { + unsigned int i = 0; + unsigned int n = 6; int ret; /* O32 ABI syscall() - Either 64-bit with O32 or 32-bit */ if ((IS_ENABLED(CONFIG_32BIT) || diff --git a/arch/mn10300/include/asm/syscall.h b/arch/mn10300/include/asm/syscall.h index b44b0bb75a01..0b2767144a60 100644 --- a/arch/mn10300/include/asm/syscall.h +++ b/arch/mn10300/include/asm/syscall.h @@ -52,34 +52,14 @@ static inline void syscall_set_return_value(struct task_struct *task, static inline void syscall_get_arguments(struct task_struct *task, struct pt_regs *regs, - unsigned int i, unsigned int n, unsigned long *args) { - switch (i) { - case 0: - if (!n--) break; - *args++ = regs->a0; - case 1: - if (!n--) break; - *args++ = regs->d1; - case 2: - if (!n--) break; - *args++ = regs->a3; - case 3: - if (!n--) break; - *args++ = regs->a2; - case 4: - if (!n--) break; - *args++ = regs->d3; - case 5: - if (!n--) break; - *args++ = regs->d2; - case 6: - if (!n--) break; - default: - BUG(); - break; - } + *args++ = regs->a0; + *args++ = regs->d1; + *args++ = regs->a3; + *args++ = regs->a2; + *args++ = regs->d3; + *args = regs->d2; } static inline void syscall_set_arguments(struct task_struct *task, diff --git a/arch/nios2/include/asm/syscall.h b/arch/nios2/include/asm/syscall.h index 9de220854c4a..964603805cbd 100644 --- a/arch/nios2/include/asm/syscall.h +++ b/arch/nios2/include/asm/syscall.h @@ -58,42 +58,14 @@ static inline void syscall_set_return_value(struct task_struct *task, } static inline void syscall_get_arguments(struct task_struct *task, - struct pt_regs *regs, unsigned int i, unsigned int n, - unsigned long *args) + struct pt_regs *regs, unsigned long *args) { - BUG_ON(i + n > 6); - - switch (i) { - case 0: - if (!n--) - break; - *args++ = regs->r4; - case 1: - if (!n--) - break; - *args++ = regs->r5; - case 2: - if (!n--) - break; - *args++ = regs->r6; - case 3: - if (!n--) - break; - *args++ = regs->r7; - case 4: - if (!n--) - break; - *args++ = regs->r8; - case 5: - if (!n--) - break; - *args++ = regs->r9; - case 6: - if (!n--) - break; - default: - BUG(); - } + *args++ = regs->r4; + *args++ = regs->r5; + *args++ = regs->r6; + *args++ = regs->r7; + *args++ = regs->r8; + *args++ = regs->r9; } static inline void syscall_set_arguments(struct task_struct *task, diff --git a/arch/openrisc/include/asm/syscall.h b/arch/openrisc/include/asm/syscall.h index 2db9f1cf0694..72607860cd55 100644 --- a/arch/openrisc/include/asm/syscall.h +++ b/arch/openrisc/include/asm/syscall.h @@ -56,11 +56,9 @@ syscall_set_return_value(struct task_struct *task, struct pt_regs *regs, static inline void syscall_get_arguments(struct task_struct *task, struct pt_regs *regs, - unsigned int i, unsigned int n, unsigned long *args) + unsigned long *args) { - BUG_ON(i + n > 6); - - memcpy(args, ®s->gpr[3 + i], n * sizeof(args[0])); + memcpy(args, ®s->gpr[3], 6 * sizeof(args[0])); } static inline void diff --git a/arch/parisc/include/asm/syscall.h b/arch/parisc/include/asm/syscall.h index 5e0b4e6bd99d..f7296bf30eb4 100644 --- a/arch/parisc/include/asm/syscall.h +++ b/arch/parisc/include/asm/syscall.h @@ -17,29 +17,15 @@ static inline long syscall_get_nr(struct task_struct *tsk, } static inline void syscall_get_arguments(struct task_struct *tsk, - struct pt_regs *regs, unsigned int i, - unsigned int n, unsigned long *args) + struct pt_regs *regs, + unsigned long *args) { - BUG_ON(i); - - switch (n) { - case 6: - args[5] = regs->gr[21]; - case 5: - args[4] = regs->gr[22]; - case 4: - args[3] = regs->gr[23]; - case 3: - args[2] = regs->gr[24]; - case 2: - args[1] = regs->gr[25]; - case 1: - args[0] = regs->gr[26]; - case 0: - break; - default: - BUG(); - } + args[5] = regs->gr[21]; + args[4] = regs->gr[22]; + args[3] = regs->gr[23]; + args[2] = regs->gr[24]; + args[1] = regs->gr[25]; + args[0] = regs->gr[26]; } static inline long syscall_get_return_value(struct task_struct *task, diff --git a/arch/powerpc/include/asm/syscall.h b/arch/powerpc/include/asm/syscall.h index ab9f3f0a8637..70dcb199c47c 100644 --- a/arch/powerpc/include/asm/syscall.h +++ b/arch/powerpc/include/asm/syscall.h @@ -66,22 +66,20 @@ static inline void syscall_set_return_value(struct task_struct *task, static inline void syscall_get_arguments(struct task_struct *task, struct pt_regs *regs, - unsigned int i, unsigned int n, unsigned long *args) { unsigned long val, mask = -1UL; - - BUG_ON(i + n > 6); + unsigned int n = 6; #ifdef CONFIG_COMPAT if (test_tsk_thread_flag(task, TIF_32BIT)) mask = 0xffffffff; #endif while (n--) { - if (n == 0 && i == 0) + if (n == 0) val = regs->orig_gpr3; else - val = regs->gpr[3 + i + n]; + val = regs->gpr[3 + n]; args[n] = val & mask; } diff --git a/arch/s390/include/asm/syscall.h b/arch/s390/include/asm/syscall.h index 6ba0bf928909..2b520aa8ad62 100644 --- a/arch/s390/include/asm/syscall.h +++ b/arch/s390/include/asm/syscall.h @@ -59,21 +59,20 @@ static inline void syscall_set_return_value(struct task_struct *task, static inline void syscall_get_arguments(struct task_struct *task, struct pt_regs *regs, - unsigned int i, unsigned int n, unsigned long *args) { unsigned long mask = -1UL; + unsigned int n = 6; - BUG_ON(i + n > 6); #ifdef CONFIG_COMPAT if (test_tsk_thread_flag(task, TIF_31BIT)) mask = 0xffffffff; #endif while (n-- > 0) - if (i + n > 0) - args[n] = regs->gprs[2 + i + n] & mask; - if (i == 0) - args[0] = regs->orig_gpr2 & mask; + if (n > 0) + args[n] = regs->gprs[2 + n] & mask; + + args[0] = regs->orig_gpr2 & mask; } static inline void syscall_set_arguments(struct task_struct *task, diff --git a/arch/sh/include/asm/syscall_32.h b/arch/sh/include/asm/syscall_32.h index 95be3b0ce0ac..09f4942c1b11 100644 --- a/arch/sh/include/asm/syscall_32.h +++ b/arch/sh/include/asm/syscall_32.h @@ -47,30 +47,16 @@ static inline void syscall_set_return_value(struct task_struct *task, static inline void syscall_get_arguments(struct task_struct *task, struct pt_regs *regs, - unsigned int i, unsigned int n, unsigned long *args) { - /* - * Do this simply for now. If we need to start supporting - * fetching arguments from arbitrary indices, this will need some - * extra logic. Presently there are no in-tree users that depend - * on this behaviour. - */ - BUG_ON(i); /* Argument pattern is: R4, R5, R6, R7, R0, R1 */ - switch (n) { - case 6: args[5] = regs->regs[1]; - case 5: args[4] = regs->regs[0]; - case 4: args[3] = regs->regs[7]; - case 3: args[2] = regs->regs[6]; - case 2: args[1] = regs->regs[5]; - case 1: args[0] = regs->regs[4]; - case 0: - break; - default: - BUG(); - } + args[5] = regs->regs[1]; + args[4] = regs->regs[0]; + args[3] = regs->regs[7]; + args[2] = regs->regs[6]; + args[1] = regs->regs[5]; + args[0] = regs->regs[4]; } static inline void syscall_set_arguments(struct task_struct *task, diff --git a/arch/sh/include/asm/syscall_64.h b/arch/sh/include/asm/syscall_64.h index c6a797b90b80..0c5d28f47827 100644 --- a/arch/sh/include/asm/syscall_64.h +++ b/arch/sh/include/asm/syscall_64.h @@ -46,11 +46,9 @@ static inline void syscall_set_return_value(struct task_struct *task, static inline void syscall_get_arguments(struct task_struct *task, struct pt_regs *regs, - unsigned int i, unsigned int n, unsigned long *args) { - BUG_ON(i + n > 6); - memcpy(args, ®s->regs[2 + i], n * sizeof(args[0])); + memcpy(args, ®s->regs[2], 6 * sizeof(args[0])); } static inline void syscall_set_arguments(struct task_struct *task, diff --git a/arch/sparc/include/asm/syscall.h b/arch/sparc/include/asm/syscall.h index 1757cd6c521b..419ed27ae60b 100644 --- a/arch/sparc/include/asm/syscall.h +++ b/arch/sparc/include/asm/syscall.h @@ -95,11 +95,11 @@ static inline void syscall_set_return_value(struct task_struct *task, static inline void syscall_get_arguments(struct task_struct *task, struct pt_regs *regs, - unsigned int i, unsigned int n, unsigned long *args) { int zero_extend = 0; unsigned int j; + unsigned int n = 6; #ifdef CONFIG_SPARC64 if (test_tsk_thread_flag(task, TIF_32BIT)) @@ -107,7 +107,7 @@ static inline void syscall_get_arguments(struct task_struct *task, #endif for (j = 0; j < n; j++) { - unsigned long val = regs->u_regs[UREG_I0 + i + j]; + unsigned long val = regs->u_regs[UREG_I0 + j]; if (zero_extend) args[j] = (u32) val; diff --git a/arch/tile/include/asm/syscall.h b/arch/tile/include/asm/syscall.h index 373d73064ea1..42c6204b3c30 100644 --- a/arch/tile/include/asm/syscall.h +++ b/arch/tile/include/asm/syscall.h @@ -76,11 +76,9 @@ static inline void syscall_set_return_value(struct task_struct *task, static inline void syscall_get_arguments(struct task_struct *task, struct pt_regs *regs, - unsigned int i, unsigned int n, unsigned long *args) { - BUG_ON(i + n > 6); - memcpy(args, ®s[i], n * sizeof(args[0])); + memcpy(args, ®s[0], 6 * sizeof(args[0])); } static inline void syscall_set_arguments(struct task_struct *task, diff --git a/arch/um/include/asm/syscall-generic.h b/arch/um/include/asm/syscall-generic.h index 9fb9cf8cd39a..25d00acd1322 100644 --- a/arch/um/include/asm/syscall-generic.h +++ b/arch/um/include/asm/syscall-generic.h @@ -53,43 +53,16 @@ static inline void syscall_set_return_value(struct task_struct *task, static inline void syscall_get_arguments(struct task_struct *task, struct pt_regs *regs, - unsigned int i, unsigned int n, unsigned long *args) { const struct uml_pt_regs *r = ®s->regs; - switch (i) { - case 0: - if (!n--) - break; - *args++ = UPT_SYSCALL_ARG1(r); - case 1: - if (!n--) - break; - *args++ = UPT_SYSCALL_ARG2(r); - case 2: - if (!n--) - break; - *args++ = UPT_SYSCALL_ARG3(r); - case 3: - if (!n--) - break; - *args++ = UPT_SYSCALL_ARG4(r); - case 4: - if (!n--) - break; - *args++ = UPT_SYSCALL_ARG5(r); - case 5: - if (!n--) - break; - *args++ = UPT_SYSCALL_ARG6(r); - case 6: - if (!n--) - break; - default: - BUG(); - break; - } + *args++ = UPT_SYSCALL_ARG1(r); + *args++ = UPT_SYSCALL_ARG2(r); + *args++ = UPT_SYSCALL_ARG3(r); + *args++ = UPT_SYSCALL_ARG4(r); + *args++ = UPT_SYSCALL_ARG5(r); + *args = UPT_SYSCALL_ARG6(r); } static inline void syscall_set_arguments(struct task_struct *task, diff --git a/arch/x86/include/asm/syscall.h b/arch/x86/include/asm/syscall.h index e3c95e8e61c5..050891169b51 100644 --- a/arch/x86/include/asm/syscall.h +++ b/arch/x86/include/asm/syscall.h @@ -87,11 +87,9 @@ static inline void syscall_set_return_value(struct task_struct *task, static inline void syscall_get_arguments(struct task_struct *task, struct pt_regs *regs, - unsigned int i, unsigned int n, unsigned long *args) { - BUG_ON(i + n > 6); - memcpy(args, ®s->bx + i, n * sizeof(args[0])); + memcpy(args, ®s->bx, 6 * sizeof(args[0])); } static inline void syscall_set_arguments(struct task_struct *task, @@ -112,63 +110,25 @@ static inline int syscall_get_arch(void) static inline void syscall_get_arguments(struct task_struct *task, struct pt_regs *regs, - unsigned int i, unsigned int n, unsigned long *args) { # ifdef CONFIG_IA32_EMULATION - if (task->thread.status & TS_COMPAT) - switch (i) { - case 0: - if (!n--) break; - *args++ = regs->bx; - case 1: - if (!n--) break; - *args++ = regs->cx; - case 2: - if (!n--) break; - *args++ = regs->dx; - case 3: - if (!n--) break; - *args++ = regs->si; - case 4: - if (!n--) break; - *args++ = regs->di; - case 5: - if (!n--) break; - *args++ = regs->bp; - case 6: - if (!n--) break; - default: - BUG(); - break; - } - else + if (task->thread.status & TS_COMPAT) { + *args++ = regs->bx; + *args++ = regs->cx; + *args++ = regs->dx; + *args++ = regs->si; + *args++ = regs->di; + *args = regs->bp; + } else { # endif - switch (i) { - case 0: - if (!n--) break; - *args++ = regs->di; - case 1: - if (!n--) break; - *args++ = regs->si; - case 2: - if (!n--) break; - *args++ = regs->dx; - case 3: - if (!n--) break; - *args++ = regs->r10; - case 4: - if (!n--) break; - *args++ = regs->r8; - case 5: - if (!n--) break; - *args++ = regs->r9; - case 6: - if (!n--) break; - default: - BUG(); - break; - } + *args++ = regs->di; + *args++ = regs->si; + *args++ = regs->dx; + *args++ = regs->r10; + *args++ = regs->r8; + *args = regs->r9; + } } static inline void syscall_set_arguments(struct task_struct *task, diff --git a/include/asm-generic/syscall.h b/include/asm-generic/syscall.h index 0c938a4354f6..269e9412ef42 100644 --- a/include/asm-generic/syscall.h +++ b/include/asm-generic/syscall.h @@ -105,21 +105,16 @@ void syscall_set_return_value(struct task_struct *task, struct pt_regs *regs, * syscall_get_arguments - extract system call parameter values * @task: task of interest, must be blocked * @regs: task_pt_regs() of @task - * @i: argument index [0,5] - * @n: number of arguments; n+i must be [1,6]. * @args: array filled with argument values * - * Fetches @n arguments to the system call starting with the @i'th argument - * (from 0 through 5). Argument @i is stored in @args[0], and so on. - * An arch inline version is probably optimal when @i and @n are constants. + * Fetches 6 arguments to the system call. First argument is stored in +* @args[0], and so on. * * It's only valid to call this when @task is stopped for tracing on * entry to a system call, due to %TIF_SYSCALL_TRACE or %TIF_SYSCALL_AUDIT. - * It's invalid to call this with @i + @n > 6; we only support system calls - * taking up to 6 arguments. */ void syscall_get_arguments(struct task_struct *task, struct pt_regs *regs, - unsigned int i, unsigned int n, unsigned long *args); + unsigned long *args); /** * syscall_set_arguments - change system call parameter value diff --git a/include/trace/events/syscalls.h b/include/trace/events/syscalls.h index 14e49c798135..72aa1694a6cf 100644 --- a/include/trace/events/syscalls.h +++ b/include/trace/events/syscalls.h @@ -26,7 +26,7 @@ TRACE_EVENT_FN(sys_enter, TP_fast_assign( __entry->id = id; - syscall_get_arguments(current, regs, 0, 6, __entry->args); + syscall_get_arguments(current, regs, __entry->args); ), TP_printk("NR %ld (%lx, %lx, %lx, %lx, %lx, %lx)", diff --git a/kernel/seccomp.c b/kernel/seccomp.c index 0db7c8a2afe2..31d1a3c04bec 100644 --- a/kernel/seccomp.c +++ b/kernel/seccomp.c @@ -75,7 +75,7 @@ static void populate_seccomp_data(struct seccomp_data *sd) sd->nr = syscall_get_nr(task, regs); sd->arch = syscall_get_arch(); - syscall_get_arguments(task, regs, 0, 6, args); + syscall_get_arguments(task, regs, args); sd->args[0] = args[0]; sd->args[1] = args[1]; sd->args[2] = args[2]; diff --git a/kernel/trace/trace_syscalls.c b/kernel/trace/trace_syscalls.c index 52c1503cedfa..3aff1f5e7fc3 100644 --- a/kernel/trace/trace_syscalls.c +++ b/kernel/trace/trace_syscalls.c @@ -347,7 +347,7 @@ static void ftrace_syscall_enter(void *data, struct pt_regs *regs, long id) entry = ring_buffer_event_data(event); entry->nr = syscall_nr; - syscall_get_arguments(current, regs, 0, 6, args); + syscall_get_arguments(current, regs, args); memcpy(entry->args, args, sizeof(unsigned long) * sys_data->nb_args); event_trigger_unlock_commit(trace_file, buffer, event, entry, @@ -595,7 +595,7 @@ static void perf_syscall_enter(void *ignore, struct pt_regs *regs, long id) return; rec->nr = syscall_nr; - syscall_get_arguments(current, regs, 0, 6, args); + syscall_get_arguments(current, regs, args); memcpy(&rec->args, args, sizeof(unsigned long) * sys_data->nb_args); perf_trace_buf_submit(rec, size, rctx, diff --git a/lib/syscall.c b/lib/syscall.c index cbd376c66bbc..cc83c9e2d682 100644 --- a/lib/syscall.c +++ b/lib/syscall.c @@ -26,7 +26,7 @@ static int collect_syscall(struct task_struct *target, long *callno, *callno = syscall_get_nr(target, regs); if (*callno != -1L) - syscall_get_arguments(target, regs, 0, 6, args); + syscall_get_arguments(target, regs, args); put_task_stack(target); return 0; -- 2.9.3
