arch/sh/kernel/sys_sh.c - maze/linux - Git at Google

 /*
  * linux/arch/sh/kernel/sys_sh.c
  *
  * This file contains various random system calls that
  * have a non-standard calling sequence on the Linux/SuperH
  * platform.
  *
  * Taken from i386 version.
  */

 #include <linux/errno.h>
 #include <linux/sched.h>
 #include <linux/mm.h>
 #include <linux/smp.h>
 #include <linux/sem.h>
 #include <linux/msg.h>
 #include <linux/shm.h>
 #include <linux/stat.h>
 #include <linux/syscalls.h>
 #include <linux/mman.h>
 #include <linux/file.h>
 #include <linux/utsname.h>
 #include <linux/module.h>
 #include <asm/cacheflush.h>
 #include <asm/uaccess.h>
 #include <asm/ipc.h>
 #include <asm/unistd.h>

 /*
  * sys_pipe() is the normal C calling standard for creating
  * a pipe. It's not the way Unix traditionally does this, though.
  */
 asmlinkage int sys_pipe(unsigned long r4, unsigned long r5,
 	unsigned long r6, unsigned long r7,
 	struct pt_regs __regs)
 {
 	struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
 	int fd[2];
 	int error;

 	error = do_pipe(fd);
 	if (!error) {
 		regs->regs[1] = fd[1];
 		return fd[0];
 	}
 	return error;
 }

 unsigned long shm_align_mask = PAGE_SIZE - 1;	/* Sane caches */

 EXPORT_SYMBOL(shm_align_mask);

 #ifdef CONFIG_MMU
 /*
  * To avoid cache aliases, we map the shared page with same color.
  */
 #define COLOUR_ALIGN(addr, pgoff)				\
 	((((addr) + shm_align_mask) & ~shm_align_mask) +	\
 	 (((pgoff) << PAGE_SHIFT) & shm_align_mask))

 unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr,
 	unsigned long len, unsigned long pgoff, unsigned long flags)
 {
 	struct mm_struct *mm = current->mm;
 	struct vm_area_struct *vma;
 	unsigned long start_addr;
 	int do_colour_align;

 	if (flags & MAP_FIXED) {
 		/* We do not accept a shared mapping if it would violate
 		 * cache aliasing constraints.
 		 */
 		if ((flags & MAP_SHARED) && (addr & shm_align_mask))
 			return -EINVAL;
 		return addr;
 	}

 	if (unlikely(len > TASK_SIZE))
 		return -ENOMEM;

 	do_colour_align = 0;
 	if (filp || (flags & MAP_SHARED))
 		do_colour_align = 1;

 	if (addr) {
 		if (do_colour_align)
 			addr = COLOUR_ALIGN(addr, pgoff);
 		else
 			addr = PAGE_ALIGN(addr);

 		vma = find_vma(mm, addr);
 		if (TASK_SIZE - len >= addr &&
 		    (!vma || addr + len <= vma->vm_start))
 			return addr;
 	}

 	if (len > mm->cached_hole_size) {
 		start_addr = addr = mm->free_area_cache;
 	} else {
 	        mm->cached_hole_size = 0;
 		start_addr = addr = TASK_UNMAPPED_BASE;
 	}

 full_search:
 	if (do_colour_align)
 		addr = COLOUR_ALIGN(addr, pgoff);
 	else
 		addr = PAGE_ALIGN(mm->free_area_cache);

 	for (vma = find_vma(mm, addr); ; vma = vma->vm_next) {
 		/* At this point:  (!vma || addr < vma->vm_end). */
 		if (unlikely(TASK_SIZE - len < addr)) {
 			/*
 			 * Start a new search - just in case we missed
 			 * some holes.
 			 */
 			if (start_addr != TASK_UNMAPPED_BASE) {
 				start_addr = addr = TASK_UNMAPPED_BASE;
 				mm->cached_hole_size = 0;
 				goto full_search;
 			}
 			return -ENOMEM;
 		}
 		if (likely(!vma || addr + len <= vma->vm_start)) {
 			/*
 			 * Remember the place where we stopped the search:
 			 */
 			mm->free_area_cache = addr + len;
 			return addr;
 		}
 		if (addr + mm->cached_hole_size < vma->vm_start)
 		        mm->cached_hole_size = vma->vm_start - addr;

 		addr = vma->vm_end;
 		if (do_colour_align)
 			addr = COLOUR_ALIGN(addr, pgoff);
 	}
 }
 #endif /* CONFIG_MMU */

 static inline long
 do_mmap2(unsigned long addr, unsigned long len, unsigned long prot,
 	 unsigned long flags, int fd, unsigned long pgoff)
 {
 	int error = -EBADF;
 	struct file *file = NULL;

 	flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
 	if (!(flags & MAP_ANONYMOUS)) {
 		file = fget(fd);
 		if (!file)
 			goto out;
 	}

 	down_write(&current->mm->mmap_sem);
 	error = do_mmap_pgoff(file, addr, len, prot, flags, pgoff);
 	up_write(&current->mm->mmap_sem);

 	if (file)
 		fput(file);
 out:
 	return error;
 }

 asmlinkage int old_mmap(unsigned long addr, unsigned long len,
 	unsigned long prot, unsigned long flags,
 	int fd, unsigned long off)
 {
 	if (off & ~PAGE_MASK)
 		return -EINVAL;
 	return do_mmap2(addr, len, prot, flags, fd, off>>PAGE_SHIFT);
 }

 asmlinkage long sys_mmap2(unsigned long addr, unsigned long len,
 	unsigned long prot, unsigned long flags,
 	unsigned long fd, unsigned long pgoff)
 {
 	return do_mmap2(addr, len, prot, flags, fd, pgoff);
 }

 /*
  * sys_ipc() is the de-multiplexer for the SysV IPC calls..
  *
  * This is really horribly ugly.
  */
 asmlinkage int sys_ipc(uint call, int first, int second,
 		       int third, void __user *ptr, long fifth)
 {
 	int version, ret;

 	version = call >> 16; /* hack for backward compatibility */
 	call &= 0xffff;

 	if (call <= SEMCTL)
 		switch (call) {
 		case SEMOP:
 			return sys_semtimedop(first, (struct sembuf __user *)ptr,
 					      second, NULL);
 		case SEMTIMEDOP:
 			return sys_semtimedop(first, (struct sembuf __user *)ptr,
 					      second,
 					      (const struct timespec __user *)fifth);
 		case SEMGET:
 			return sys_semget (first, second, third);
 		case SEMCTL: {
 			union semun fourth;
 			if (!ptr)
 				return -EINVAL;
 			if (get_user(fourth.__pad, (void * __user *) ptr))
 				return -EFAULT;
 			return sys_semctl (first, second, third, fourth);
 			}
 		default:
 			return -EINVAL;
 		}

 	if (call <= MSGCTL)
 		switch (call) {
 		case MSGSND:
 			return sys_msgsnd (first, (struct msgbuf __user *) ptr,
 					  second, third);
 		case MSGRCV:
 			switch (version) {
 			case 0: {
 				struct ipc_kludge tmp;
 				if (!ptr)
 					return -EINVAL;

 				if (copy_from_user(&tmp,
 						   (struct ipc_kludge __user *) ptr,
 						   sizeof (tmp)))
 					return -EFAULT;
 				return sys_msgrcv (first, tmp.msgp, second,
 						   tmp.msgtyp, third);
 				}
 			default:
 				return sys_msgrcv (first,
 						   (struct msgbuf __user *) ptr,
 						   second, fifth, third);
 			}
 		case MSGGET:
 			return sys_msgget ((key_t) first, second);
 		case MSGCTL:
 			return sys_msgctl (first, second,
 					   (struct msqid_ds __user *) ptr);
 		default:
 			return -EINVAL;
 		}
 	if (call <= SHMCTL)
 		switch (call) {
 		case SHMAT:
 			switch (version) {
 			default: {
 				ulong raddr;
 				ret = do_shmat (first, (char __user *) ptr,
 						 second, &raddr);
 				if (ret)
 					return ret;
 				return put_user (raddr, (ulong __user *) third);
 			}
 			case 1:	/* iBCS2 emulator entry point */
 				if (!segment_eq(get_fs(), get_ds()))
 					return -EINVAL;
 				return do_shmat (first, (char __user *) ptr,
 						  second, (ulong *) third);
 			}
 		case SHMDT:
 			return sys_shmdt ((char __user *)ptr);
 		case SHMGET:
 			return sys_shmget (first, second, third);
 		case SHMCTL:
 			return sys_shmctl (first, second,
 					   (struct shmid_ds __user *) ptr);
 		default:
 			return -EINVAL;
 		}

 	return -EINVAL;
 }

 asmlinkage int sys_uname(struct old_utsname * name)
 {
 	int err;
 	if (!name)
 		return -EFAULT;
 	down_read(&uts_sem);
 	err = copy_to_user(name, utsname(), sizeof (*name));
 	up_read(&uts_sem);
 	return err?-EFAULT:0;
 }

 asmlinkage ssize_t sys_pread_wrapper(unsigned int fd, char * buf,
 			     size_t count, long dummy, loff_t pos)
 {
 	return sys_pread64(fd, buf, count, pos);
 }

 asmlinkage ssize_t sys_pwrite_wrapper(unsigned int fd, const char * buf,
 			      size_t count, long dummy, loff_t pos)
 {
 	return sys_pwrite64(fd, buf, count, pos);
 }

 asmlinkage int sys_fadvise64_64_wrapper(int fd, u32 offset0, u32 offset1,
 				u32 len0, u32 len1, int advice)
 {
 #ifdef  __LITTLE_ENDIAN__
 	return sys_fadvise64_64(fd, (u64)offset1 << 32 | offset0,
 				(u64)len1 << 32 | len0,	advice);
 #else
 	return sys_fadvise64_64(fd, (u64)offset0 << 32 | offset1,
 				(u64)len0 << 32 | len1,	advice);
 #endif
 }

 #if defined(CONFIG_CPU_SH2) || defined(CONFIG_CPU_SH2A)
 #define SYSCALL_ARG3	"trapa #0x23"
 #else
 #define SYSCALL_ARG3	"trapa #0x13"
 #endif

 /*
  * Do a system call from kernel instead of calling sys_execve so we
  * end up with proper pt_regs.
  */
 int kernel_execve(const char *filename, char *const argv[], char *const envp[])
 {
 	register long __sc0 __asm__ ("r3") = __NR_execve;
 	register long __sc4 __asm__ ("r4") = (long) filename;
 	register long __sc5 __asm__ ("r5") = (long) argv;
 	register long __sc6 __asm__ ("r6") = (long) envp;
 	__asm__ __volatile__ (SYSCALL_ARG3 : "=z" (__sc0)
 			: "0" (__sc0), "r" (__sc4), "r" (__sc5), "r" (__sc6)
 			: "memory");
 	return __sc0;
 }
	/*
	* linux/arch/sh/kernel/sys_sh.c
	*
	* This file contains various random system calls that
	* have a non-standard calling sequence on the Linux/SuperH
	* platform.
	*
	* Taken from i386 version.
	*/

	#include <linux/errno.h>
	#include <linux/sched.h>
	#include <linux/mm.h>
	#include <linux/smp.h>
	#include <linux/sem.h>
	#include <linux/msg.h>
	#include <linux/shm.h>
	#include <linux/stat.h>
	#include <linux/syscalls.h>
	#include <linux/mman.h>
	#include <linux/file.h>
	#include <linux/utsname.h>
	#include <linux/module.h>
	#include <asm/cacheflush.h>
	#include <asm/uaccess.h>
	#include <asm/ipc.h>
	#include <asm/unistd.h>

	/*
	* sys_pipe() is the normal C calling standard for creating
	* a pipe. It's not the way Unix traditionally does this, though.
	*/
	asmlinkage int sys_pipe(unsigned long r4, unsigned long r5,
	unsigned long r6, unsigned long r7,
	struct pt_regs __regs)
	{
	struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
	int fd[2];
	int error;

	error = do_pipe(fd);
	if (!error) {
	regs->regs[1] = fd[1];
	return fd[0];
	}
	return error;
	}

	unsigned long shm_align_mask = PAGE_SIZE - 1; /* Sane caches */

	EXPORT_SYMBOL(shm_align_mask);

	#ifdef CONFIG_MMU
	/*
	* To avoid cache aliases, we map the shared page with same color.
	*/
	#define COLOUR_ALIGN(addr, pgoff) \
	((((addr) + shm_align_mask) & ~shm_align_mask) + \
	(((pgoff) << PAGE_SHIFT) & shm_align_mask))

	unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr,
	unsigned long len, unsigned long pgoff, unsigned long flags)
	{
	struct mm_struct *mm = current->mm;
	struct vm_area_struct *vma;
	unsigned long start_addr;
	int do_colour_align;

	if (flags & MAP_FIXED) {
	/* We do not accept a shared mapping if it would violate
	* cache aliasing constraints.
	*/
	if ((flags & MAP_SHARED) && (addr & shm_align_mask))
	return -EINVAL;
	return addr;
	}

	if (unlikely(len > TASK_SIZE))
	return -ENOMEM;

	do_colour_align = 0;
	if (filp \|\| (flags & MAP_SHARED))
	do_colour_align = 1;

	if (addr) {
	if (do_colour_align)
	addr = COLOUR_ALIGN(addr, pgoff);
	else
	addr = PAGE_ALIGN(addr);

	vma = find_vma(mm, addr);
	if (TASK_SIZE - len >= addr &&
	(!vma \|\| addr + len <= vma->vm_start))
	return addr;
	}

	if (len > mm->cached_hole_size) {
	start_addr = addr = mm->free_area_cache;
	} else {
	mm->cached_hole_size = 0;
	start_addr = addr = TASK_UNMAPPED_BASE;
	}

	full_search:
	if (do_colour_align)
	addr = COLOUR_ALIGN(addr, pgoff);
	else
	addr = PAGE_ALIGN(mm->free_area_cache);

	for (vma = find_vma(mm, addr); ; vma = vma->vm_next) {
	/* At this point: (!vma \|\| addr < vma->vm_end). */
	if (unlikely(TASK_SIZE - len < addr)) {
	/*
	* Start a new search - just in case we missed
	* some holes.
	*/
	if (start_addr != TASK_UNMAPPED_BASE) {
	start_addr = addr = TASK_UNMAPPED_BASE;
	mm->cached_hole_size = 0;
	goto full_search;
	}
	return -ENOMEM;
	}
	if (likely(!vma \|\| addr + len <= vma->vm_start)) {
	/*
	* Remember the place where we stopped the search:
	*/
	mm->free_area_cache = addr + len;
	return addr;
	}
	if (addr + mm->cached_hole_size < vma->vm_start)
	mm->cached_hole_size = vma->vm_start - addr;

	addr = vma->vm_end;
	if (do_colour_align)
	addr = COLOUR_ALIGN(addr, pgoff);
	}
	}
	#endif /* CONFIG_MMU */

	static inline long
	do_mmap2(unsigned long addr, unsigned long len, unsigned long prot,
	unsigned long flags, int fd, unsigned long pgoff)
	{
	int error = -EBADF;
	struct file *file = NULL;

	flags &= ~(MAP_EXECUTABLE \| MAP_DENYWRITE);
	if (!(flags & MAP_ANONYMOUS)) {
	file = fget(fd);
	if (!file)
	goto out;
	}

	down_write(&current->mm->mmap_sem);
	error = do_mmap_pgoff(file, addr, len, prot, flags, pgoff);
	up_write(&current->mm->mmap_sem);

	if (file)
	fput(file);
	out:
	return error;
	}

	asmlinkage int old_mmap(unsigned long addr, unsigned long len,
	unsigned long prot, unsigned long flags,
	int fd, unsigned long off)
	{
	if (off & ~PAGE_MASK)
	return -EINVAL;
	return do_mmap2(addr, len, prot, flags, fd, off>>PAGE_SHIFT);
	}

	asmlinkage long sys_mmap2(unsigned long addr, unsigned long len,
	unsigned long prot, unsigned long flags,
	unsigned long fd, unsigned long pgoff)
	{
	return do_mmap2(addr, len, prot, flags, fd, pgoff);
	}

	/*
	* sys_ipc() is the de-multiplexer for the SysV IPC calls..
	*
	* This is really horribly ugly.
	*/
	asmlinkage int sys_ipc(uint call, int first, int second,
	int third, void __user *ptr, long fifth)
	{
	int version, ret;

	version = call >> 16; /* hack for backward compatibility */
	call &= 0xffff;

	if (call <= SEMCTL)
	switch (call) {
	case SEMOP:
	return sys_semtimedop(first, (struct sembuf __user *)ptr,
	second, NULL);
	case SEMTIMEDOP:
	return sys_semtimedop(first, (struct sembuf __user *)ptr,
	second,
	(const struct timespec __user *)fifth);
	case SEMGET:
	return sys_semget (first, second, third);
	case SEMCTL: {
	union semun fourth;
	if (!ptr)
	return -EINVAL;
	if (get_user(fourth.__pad, (void * __user *) ptr))
	return -EFAULT;
	return sys_semctl (first, second, third, fourth);
	}
	default:
	return -EINVAL;
	}

	if (call <= MSGCTL)
	switch (call) {
	case MSGSND:
	return sys_msgsnd (first, (struct msgbuf __user *) ptr,
	second, third);
	case MSGRCV:
	switch (version) {
	case 0: {
	struct ipc_kludge tmp;
	if (!ptr)
	return -EINVAL;

	if (copy_from_user(&tmp,
	(struct ipc_kludge __user *) ptr,
	sizeof (tmp)))
	return -EFAULT;
	return sys_msgrcv (first, tmp.msgp, second,
	tmp.msgtyp, third);
	}
	default:
	return sys_msgrcv (first,
	(struct msgbuf __user *) ptr,
	second, fifth, third);
	}
	case MSGGET:
	return sys_msgget ((key_t) first, second);
	case MSGCTL:
	return sys_msgctl (first, second,
	(struct msqid_ds __user *) ptr);
	default:
	return -EINVAL;
	}
	if (call <= SHMCTL)
	switch (call) {
	case SHMAT:
	switch (version) {
	default: {
	ulong raddr;
	ret = do_shmat (first, (char __user *) ptr,
	second, &raddr);
	if (ret)
	return ret;
	return put_user (raddr, (ulong __user *) third);
	}
	case 1: /* iBCS2 emulator entry point */
	if (!segment_eq(get_fs(), get_ds()))
	return -EINVAL;
	return do_shmat (first, (char __user *) ptr,
	second, (ulong *) third);
	}
	case SHMDT:
	return sys_shmdt ((char __user *)ptr);
	case SHMGET:
	return sys_shmget (first, second, third);
	case SHMCTL:
	return sys_shmctl (first, second,
	(struct shmid_ds __user *) ptr);
	default:
	return -EINVAL;
	}

	return -EINVAL;
	}

	asmlinkage int sys_uname(struct old_utsname * name)
	{
	int err;
	if (!name)
	return -EFAULT;
	down_read(&uts_sem);
	err = copy_to_user(name, utsname(), sizeof (*name));
	up_read(&uts_sem);
	return err?-EFAULT:0;
	}

	asmlinkage ssize_t sys_pread_wrapper(unsigned int fd, char * buf,
	size_t count, long dummy, loff_t pos)
	{
	return sys_pread64(fd, buf, count, pos);
	}

	asmlinkage ssize_t sys_pwrite_wrapper(unsigned int fd, const char * buf,
	size_t count, long dummy, loff_t pos)
	{
	return sys_pwrite64(fd, buf, count, pos);
	}

	asmlinkage int sys_fadvise64_64_wrapper(int fd, u32 offset0, u32 offset1,
	u32 len0, u32 len1, int advice)
	{
	#ifdef __LITTLE_ENDIAN__
	return sys_fadvise64_64(fd, (u64)offset1 << 32 \| offset0,
	(u64)len1 << 32 \| len0, advice);
	#else
	return sys_fadvise64_64(fd, (u64)offset0 << 32 \| offset1,
	(u64)len0 << 32 \| len1, advice);
	#endif
	}

	#if defined(CONFIG_CPU_SH2) \|\| defined(CONFIG_CPU_SH2A)
	#define SYSCALL_ARG3 "trapa #0x23"
	#else
	#define SYSCALL_ARG3 "trapa #0x13"
	#endif

	/*
	* Do a system call from kernel instead of calling sys_execve so we
	* end up with proper pt_regs.
	*/
	int kernel_execve(const char filename, char const argv[], char *const envp[])
	{
	register long __sc0 __asm__ ("r3") = __NR_execve;
	register long __sc4 __asm__ ("r4") = (long) filename;
	register long __sc5 __asm__ ("r5") = (long) argv;
	register long __sc6 __asm__ ("r6") = (long) envp;
	__asm__ __volatile__ (SYSCALL_ARG3 : "=z" (__sc0)
	: "0" (__sc0), "r" (__sc4), "r" (__sc5), "r" (__sc6)
	: "memory");
	return __sc0;
	}