| Message ID | 20220725062845.119908-1-rmclure@linux.ibm.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | powerpc: Syscall wrapper and register clearing | expand |
On Mon, 2022-07-25 at 16:28 +1000, Rohan McLure wrote: > Cause syscall handlers to be typed as follows when called indirectly > throughout the kernel. > > typedef long (*syscall_fn)(unsigned long, unsigned long, unsigned > long, > unsigned long, unsigned long, unsigned > long); > > Since both 32 and 64-bit abis allow for at least the first six > machine-word length parameters to a function to be passed by > registers, > even handlers which admit fewer than six parameters may be viewed as > having the above type. > > Fixup comparisons in VDSO to avoid pointer-integer comparison. > Introduce > explicit cast on systems with SPUs. > > Signed-off-by: Rohan McLure <rmclure@linux.ibm.com> This patch needs rebasing on top of commit 1547db7d1f44 ("powerpc: Move system_call_exception() to syscall.c"). > > diff --git a/arch/powerpc/platforms/cell/spu_callbacks.c > b/arch/powerpc/platforms/cell/spu_callbacks.c > index fe0d8797a00a..114bbe2eeacc 100644 > --- a/arch/powerpc/platforms/cell/spu_callbacks.c > +++ b/arch/powerpc/platforms/cell/spu_callbacks.c > @@ -34,22 +34,22 @@ > * mbind, mq_open, ipc, ... > */ > > -static void *spu_syscall_table[] = { > +static const syscall_fn spu_syscall_table[] = { > #define __SYSCALL_WITH_COMPAT(nr, entry, compat) __SYSCALL(nr, > entry) > -#define __SYSCALL(nr, entry) [nr] = entry, > +#define __SYSCALL(nr, entry) [nr] = (void *) entry, > #include <asm/syscall_table_spu.h> > }; > > long spu_sys_callback(struct spu_syscall_block *s) > { > - long (*syscall)(u64 a1, u64 a2, u64 a3, u64 a4, u64 a5, u64 > a6); > + syscall_fn syscall; > > if (s->nr_ret >= ARRAY_SIZE(spu_syscall_table)) { > pr_debug("%s: invalid syscall #%lld", __func__, s- > >nr_ret); > return -ENOSYS; > } > > - syscall = spu_syscall_table[s->nr_ret]; > + syscall = (syscall_fn) spu_syscall_table[s->nr_ret]; I don't think this cast is necessary? > > pr_debug("SPU-syscall " > "%pSR:syscall%lld(%llx, %llx, %llx, %llx, %llx, > %llx)\n",
diff --git a/arch/powerpc/include/asm/syscall.h b/arch/powerpc/include/asm/syscall.h index 25fc8ad9a27a..d2a8dfd5de33 100644 --- a/arch/powerpc/include/asm/syscall.h +++ b/arch/powerpc/include/asm/syscall.h @@ -14,9 +14,12 @@ #include <linux/sched.h> #include <linux/thread_info.h> +typedef long (*syscall_fn)(unsigned long, unsigned long, unsigned long, + unsigned long, unsigned long, unsigned long); + /* ftrace syscalls requires exporting the sys_call_table */ -extern const unsigned long sys_call_table[]; -extern const unsigned long compat_sys_call_table[]; +extern const syscall_fn sys_call_table[]; +extern const syscall_fn compat_sys_call_table[]; static inline int syscall_get_nr(struct task_struct *task, struct pt_regs *regs) { diff --git a/arch/powerpc/include/asm/syscalls.h b/arch/powerpc/include/asm/syscalls.h index 8b2757d7f423..fbeab8e88c5e 100644 --- a/arch/powerpc/include/asm/syscalls.h +++ b/arch/powerpc/include/asm/syscalls.h @@ -8,6 +8,7 @@ #include <linux/types.h> #include <linux/compat.h> +#include <asm/syscall.h> #ifdef CONFIG_PPC64 #include <asm/ppc32.h> #endif diff --git a/arch/powerpc/kernel/interrupt.c b/arch/powerpc/kernel/interrupt.c index 784ea3289c84..62e636e0f684 100644 --- a/arch/powerpc/kernel/interrupt.c +++ b/arch/powerpc/kernel/interrupt.c @@ -24,8 +24,6 @@ unsigned long global_dbcr0[NR_CPUS]; #endif -typedef long (*syscall_fn)(long, long, long, long, long, long); - #ifdef CONFIG_PPC_BOOK3S_64 DEFINE_STATIC_KEY_FALSE(interrupt_exit_not_reentrant); static inline bool exit_must_hard_disable(void) diff --git a/arch/powerpc/kernel/systbl.c b/arch/powerpc/kernel/systbl.c index 99ffdfef6b9c..b88a9c2a1f50 100644 --- a/arch/powerpc/kernel/systbl.c +++ b/arch/powerpc/kernel/systbl.c @@ -21,10 +21,10 @@ #define __SYSCALL(nr, entry) [nr] = __powerpc_##entry, #define __powerpc_sys_ni_syscall sys_ni_syscall #else -#define __SYSCALL(nr, entry) [nr] = entry, +#define __SYSCALL(nr, entry) [nr] = (void *) entry, #endif -void *sys_call_table[] = { +const syscall_fn sys_call_table[] = { #ifdef CONFIG_PPC64 #include <asm/syscall_table_64.h> #else @@ -35,7 +35,7 @@ void *sys_call_table[] = { #ifdef CONFIG_COMPAT #undef __SYSCALL_WITH_COMPAT #define __SYSCALL_WITH_COMPAT(nr, native, compat) __SYSCALL(nr, compat) -void *compat_sys_call_table[] = { +const syscall_fn compat_sys_call_table[] = { #include <asm/syscall_table_32.h> }; #endif /* CONFIG_COMPAT */ diff --git a/arch/powerpc/kernel/vdso.c b/arch/powerpc/kernel/vdso.c index 0da287544054..080c9e7de0c0 100644 --- a/arch/powerpc/kernel/vdso.c +++ b/arch/powerpc/kernel/vdso.c @@ -313,10 +313,10 @@ static void __init vdso_setup_syscall_map(void) unsigned int i; for (i = 0; i < NR_syscalls; i++) { - if (sys_call_table[i] != (unsigned long)&sys_ni_syscall) + if (sys_call_table[i] != (void *)&sys_ni_syscall) vdso_data->syscall_map[i >> 5] |= 0x80000000UL >> (i & 0x1f); if (IS_ENABLED(CONFIG_COMPAT) && - compat_sys_call_table[i] != (unsigned long)&sys_ni_syscall) + compat_sys_call_table[i] != (void *)&sys_ni_syscall) vdso_data->compat_syscall_map[i >> 5] |= 0x80000000UL >> (i & 0x1f); } } diff --git a/arch/powerpc/platforms/cell/spu_callbacks.c b/arch/powerpc/platforms/cell/spu_callbacks.c index fe0d8797a00a..114bbe2eeacc 100644 --- a/arch/powerpc/platforms/cell/spu_callbacks.c +++ b/arch/powerpc/platforms/cell/spu_callbacks.c @@ -34,22 +34,22 @@ * mbind, mq_open, ipc, ... */ -static void *spu_syscall_table[] = { +static const syscall_fn spu_syscall_table[] = { #define __SYSCALL_WITH_COMPAT(nr, entry, compat) __SYSCALL(nr, entry) -#define __SYSCALL(nr, entry) [nr] = entry, +#define __SYSCALL(nr, entry) [nr] = (void *) entry, #include <asm/syscall_table_spu.h> }; long spu_sys_callback(struct spu_syscall_block *s) { - long (*syscall)(u64 a1, u64 a2, u64 a3, u64 a4, u64 a5, u64 a6); + syscall_fn syscall; if (s->nr_ret >= ARRAY_SIZE(spu_syscall_table)) { pr_debug("%s: invalid syscall #%lld", __func__, s->nr_ret); return -ENOSYS; } - syscall = spu_syscall_table[s->nr_ret]; + syscall = (syscall_fn) spu_syscall_table[s->nr_ret]; pr_debug("SPU-syscall " "%pSR:syscall%lld(%llx, %llx, %llx, %llx, %llx, %llx)\n",
Cause syscall handlers to be typed as follows when called indirectly throughout the kernel. typedef long (*syscall_fn)(unsigned long, unsigned long, unsigned long, unsigned long, unsigned long, unsigned long); Since both 32 and 64-bit abis allow for at least the first six machine-word length parameters to a function to be passed by registers, even handlers which admit fewer than six parameters may be viewed as having the above type. Fixup comparisons in VDSO to avoid pointer-integer comparison. Introduce explicit cast on systems with SPUs. Signed-off-by: Rohan McLure <rmclure@linux.ibm.com> --- V1 -> V2: New patch. --- arch/powerpc/include/asm/syscall.h | 7 +++++-- arch/powerpc/include/asm/syscalls.h | 1 + arch/powerpc/kernel/interrupt.c | 2 -- arch/powerpc/kernel/systbl.c | 6 +++--- arch/powerpc/kernel/vdso.c | 4 ++-- arch/powerpc/platforms/cell/spu_callbacks.c | 8 ++++---- 6 files changed, 15 insertions(+), 13 deletions(-)