This does the s390 hook for v11 of clone-with-pids. This patch is on top of the linux-cr tree. A pair of patches against user-cr is coming next to (a) make restart work with the new clone-with-pids, and (b) demonstrate clone-with-pids more generally using the ns_exec (namespace manipulation) program.
The full kernel tree/changelog can be seen as branch cwp.2 at http://git.kernel.org/gitweb.cgi?p=linux/kernel/git/sergeh/linux-cr.git The user-space clone-with-pids glue for s390 (clone_s390x.c from the user-cr package) is now: struct pid_set { int num_pids; pid_t *pids; }; typedef unsigned long long u64; typedef unsigned int u32; typedef int pid_t; struct clone_args { u64 clone_flags_high; u64 child_stack_base; u64 child_stack_size; u64 parent_tid_ptr; u64 child_tid_ptr; u32 nr_pids; u32 reserved0; u64 reserved1; }; #define do_cwp(flags, pids, args, sz) \ ( { \ register unsigned long int __r1 asm ("1") = (unsigned long int)(__NR_clone_with_pids); \ register unsigned long int __r2 asm ("2") = (unsigned long int)(flags); \ register unsigned long int __r3 asm ("3") = (unsigned long int)(args); \ register unsigned long int __r4 asm ("4") = (unsigned long int)(sz); \ register unsigned long int __r5 asm ("5") = (unsigned long int)(pids); \ register long int __result asm ("2"); \ __asm__ __volatile__( \ " svc 0\n" /* do __NR_cwp syscall */ \ " ltgr %%r2,%%r2\n" /* returned 0? */ \ " jnz 1f\n" /* if not goto label 1 */ \ " lg %%r3,0(%%r15)\n" /* get fnarg off stack into arg 1 */ \ " lg %%r2,8(%%r15)\n" /* get fn off stack int r3 basr*/ \ " lgr %%r1,%%r15\n" /* tmp store old stack pointer */ \ " aghi %%r15,-160\n" /* move the stack */ \ " stg %%r1,0(%%r15)\n" /* and save old stack pointer */ \ " basr %%r14,%%r3\n" /* call fn(arg) */ \ " svc 1\n" /* call exit */ \ " 1:\n" \ : "=d" (__result) \ : "d" (__r1), "0" (__r2), "d" (__r3), "d" (__r4), "d" (__r5) \ : "memory"); \ __result; \ } ) int clone_with_pids(int (*fn)(void *), void *child_stack, unsigned long stack_size, unsigned long flags, struct pid_set *target_pids, void *arg) { struct clone_args clone_args, *ca = &clone_args; u64 *s; memset(ca, 0, sizeof(struct clone_args)); ca->nr_pids = target_pids->num_pids; ca->child_stack_size = stack_size - 16; ca->child_stack_base = (u64) child_stack; if (child_stack) { s = (u64 *) (ca->child_stack_base + ca->child_stack_size); *--s = (u64) arg; *--s = (u64) fn; ca->child_stack_size -= 16; } return do_cwp(flags, target_pids->pids, ca, sizeof(struct clone_args)); } Changelog: Nov 09: fix compat code (thanks, Suka) Nov 10: use orig_gpr2, not gprs[2] for input arg 1 --- arch/s390/kernel/compat_linux.c | 63 ++++++++++++++++++++++++++++++-------- arch/s390/kernel/process.c | 58 +++++++++++++++++++++++++++-------- 2 files changed, 94 insertions(+), 27 deletions(-) diff --git a/arch/s390/kernel/compat_linux.c b/arch/s390/kernel/compat_linux.c index c6dc681..e26ad2c 100644 --- a/arch/s390/kernel/compat_linux.c +++ b/arch/s390/kernel/compat_linux.c @@ -821,20 +821,55 @@ asmlinkage long sys32_clone(void) asmlinkage long sys32_clone_with_pids(void) { struct pt_regs *regs = task_pt_regs(current); - unsigned long clone_flags; - unsigned long newsp; - int __user *parent_tidptr, *child_tidptr; - void __user *upid_setp; - - clone_flags = regs->gprs[3] & 0xffffffffUL; - newsp = regs->orig_gpr2 & 0x7fffffffUL; - parent_tidptr = compat_ptr(regs->gprs[4]); - child_tidptr = compat_ptr(regs->gprs[5]); - upid_setp = compat_ptr(regs->gprs[7]); - if (!newsp) - newsp = regs->gprs[15]; - return do_fork_with_pids(clone_flags, newsp, regs, 0, - parent_tidptr, child_tidptr, upid_setp); + int rc; + int args_size; + struct clone_args kca; + unsigned long flags; + int __user *parent_tid_ptr; + int __user *child_tid_ptr; + unsigned long __user child_stack; + unsigned long stack_size; + unsigned int flags_low; + struct clone_args __user *uca; + pid_t __user *pids; + + flags_low = regs->orig_gpr2 & 0xffffffffUL; + uca = compat_ptr(regs->gprs[3]); + args_size = regs->gprs[4] & 0xffffffffUL; + pids = compat_ptr(regs->gprs[5]); + + rc = fetch_clone_args_from_user(uca, args_size, &kca); + if (rc) + return rc; + + /* + * TODO: Convert 'clone-flags' to 64-bits on all architectures. + * TODO: When ->clone_flags_high is non-zero, copy it in to the + * higher word(s) of 'flags': + * + * flags = (kca.clone_flags_high << 32) | flags_low; + */ + flags = flags_low; + parent_tid_ptr = (int *)kca.parent_tid_ptr; + child_tid_ptr = (int *)kca.child_tid_ptr; + + stack_size = (unsigned long)kca.child_stack_size; + child_stack = (unsigned long)kca.child_stack_base; + if (child_stack) + child_stack += stack_size; + else + child_stack = regs->gprs[15]; + + if (!child_stack) + child_stack = regs->gprs[15]; + + /* + * TODO: On 32-bit systems, clone_flags is passed in as 32-bit value + * to several functions. Need to convert clone_flags to 64-bit. + */ + return do_fork_with_pids(flags, child_stack, regs, stack_size, + parent_tid_ptr, child_tid_ptr, kca.nr_pids, + pids); } /* diff --git a/arch/s390/kernel/process.c b/arch/s390/kernel/process.c index 263d3ab..865e791 100644 --- a/arch/s390/kernel/process.c +++ b/arch/s390/kernel/process.c @@ -250,20 +250,52 @@ SYSCALL_DEFINE0(clone) SYSCALL_DEFINE0(clone_with_pids) { struct pt_regs *regs = task_pt_regs(current); - unsigned long clone_flags; - unsigned long newsp; - int __user *parent_tidptr, *child_tidptr; - void __user *upid_setp; + int rc; + int args_size; + struct clone_args kca; + unsigned long flags; + int __user *parent_tid_ptr; + int __user *child_tid_ptr; + unsigned long __user child_stack; + unsigned long stack_size; + unsigned long flags_low; + struct clone_args __user *uca; + pid_t __user *pids; + + flags_low = regs->orig_gpr2; + uca = (struct clone_args __user *)regs->gprs[3]; + args_size = regs->gprs[4]; + pids = (pid_t __user *)regs->gprs[5]; + + rc = fetch_clone_args_from_user(uca, args_size, &kca); + if (rc) + return rc; - clone_flags = regs->gprs[3]; - newsp = regs->orig_gpr2; - parent_tidptr = (int __user *) regs->gprs[4]; - child_tidptr = (int __user *) regs->gprs[5]; - upid_setp = (void __user *) regs->gprs[7]; - if (!newsp) - newsp = regs->gprs[15]; - return do_fork_with_pids(clone_flags, newsp, regs, 0, parent_tidptr, - child_tidptr, upid_setp); + /* + * TODO: Convert 'clone-flags' to 64-bits on all architectures. + * TODO: When ->clone_flags_high is non-zero, copy it in to the + * higher word(s) of 'flags': + * + * flags = (kca.clone_flags_high << 32) | flags_low; + */ + flags = flags_low; + parent_tid_ptr = (int *)kca.parent_tid_ptr; + child_tid_ptr = (int *)kca.child_tid_ptr; + + stack_size = (unsigned long)kca.child_stack_size; + child_stack = (unsigned long)kca.child_stack_base; + if (child_stack) + child_stack += stack_size; + else + child_stack = regs->gprs[15]; + + /* + * TODO: On 32-bit systems, clone_flags is passed in as 32-bit value + * to several functions. Need to convert clone_flags to 64-bit. + */ + return do_fork_with_pids(flags, child_stack, regs, stack_size, + parent_tid_ptr, child_tid_ptr, kca.nr_pids, + pids); } /* -- 1.6.1 _______________________________________________ Containers mailing list [email protected] https://lists.linux-foundation.org/mailman/listinfo/containers _______________________________________________ Devel mailing list [email protected] https://openvz.org/mailman/listinfo/devel
