Commit 3523a9d4 authored by Christoph Hellwig's avatar Christoph Hellwig Committed by Al Viro
Browse files

fs: remove various compat readv/writev helpers 



Now that import_iovec handles compat iovecs as well, all the duplicated
code in the compat readv/writev helpers is not needed.  Remove them
and switch the compat syscall handlers to use the native helpers.

Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
parent 89cd35c5

fs/read_write.c

+30 −149
Original line number Diff line number Diff line
@@ -1068,226 +1068,107 @@ SYSCALL_DEFINE6(pwritev2, unsigned long, fd, const struct iovec __user *, vec, 
	return do_pwritev(fd, vec, vlen, pos, flags);

}



/*

 * Various compat syscalls.  Note that they all pretend to take a native

 * iovec - import_iovec will properly treat those as compat_iovecs based on

 * in_compat_syscall().

 */

#ifdef CONFIG_COMPAT

static size_t compat_readv(struct file *file,

			   const struct compat_iovec __user *vec,

			   unsigned long vlen, loff_t *pos, rwf_t flags)

{

	struct iovec iovstack[UIO_FASTIOV];

	struct iovec *iov = iovstack;

	struct iov_iter iter;

	ssize_t ret;



	ret = import_iovec(READ, (const struct iovec __user *)vec, vlen,

			   UIO_FASTIOV, &iov, &iter);

	if (ret >= 0) {

		ret = do_iter_read(file, &iter, pos, flags);

		kfree(iov);

	}

	if (ret > 0)

		add_rchar(current, ret);

	inc_syscr(current);

	return ret;

}



static size_t do_compat_readv(compat_ulong_t fd,

				 const struct compat_iovec __user *vec,

				 compat_ulong_t vlen, rwf_t flags)

{

	struct fd f = fdget_pos(fd);

	ssize_t ret;

	loff_t pos;



	if (!f.file)

		return -EBADF;

	pos = f.file->f_pos;

	ret = compat_readv(f.file, vec, vlen, &pos, flags);

	if (ret >= 0)

		f.file->f_pos = pos;

	fdput_pos(f);

	return ret;



}



COMPAT_SYSCALL_DEFINE3(readv, compat_ulong_t, fd,

		const struct compat_iovec __user *,vec,

		const struct iovec __user *, vec,

		compat_ulong_t, vlen)

{

	return do_compat_readv(fd, vec, vlen, 0);

}



static long do_compat_preadv64(unsigned long fd,

				  const struct compat_iovec __user *vec,

				  unsigned long vlen, loff_t pos, rwf_t flags)

{

	struct fd f;

	ssize_t ret;



	if (pos < 0)

		return -EINVAL;

	f = fdget(fd);

	if (!f.file)

		return -EBADF;

	ret = -ESPIPE;

	if (f.file->f_mode & FMODE_PREAD)

		ret = compat_readv(f.file, vec, vlen, &pos, flags);

	fdput(f);

	return ret;

	return do_readv(fd, vec, vlen, 0);

}



#ifdef __ARCH_WANT_COMPAT_SYS_PREADV64

COMPAT_SYSCALL_DEFINE4(preadv64, unsigned long, fd,

		const struct compat_iovec __user *,vec,

		const struct iovec __user *, vec,

		unsigned long, vlen, loff_t, pos)

{

	return do_compat_preadv64(fd, vec, vlen, pos, 0);

	return do_preadv(fd, vec, vlen, pos, 0);

}

#endif



COMPAT_SYSCALL_DEFINE5(preadv, compat_ulong_t, fd,

		const struct compat_iovec __user *,vec,

		const struct iovec __user *, vec,

		compat_ulong_t, vlen, u32, pos_low, u32, pos_high)

{

	loff_t pos = ((loff_t)pos_high << 32) | pos_low;



	return do_compat_preadv64(fd, vec, vlen, pos, 0);

	return do_preadv(fd, vec, vlen, pos, 0);

}



#ifdef __ARCH_WANT_COMPAT_SYS_PREADV64V2

COMPAT_SYSCALL_DEFINE5(preadv64v2, unsigned long, fd,

		const struct compat_iovec __user *,vec,

		const struct iovec __user *, vec,

		unsigned long, vlen, loff_t, pos, rwf_t, flags)

{

	if (pos == -1)

		return do_compat_readv(fd, vec, vlen, flags);



	return do_compat_preadv64(fd, vec, vlen, pos, flags);

		return do_readv(fd, vec, vlen, flags);

	return do_preadv(fd, vec, vlen, pos, flags);

}

#endif



COMPAT_SYSCALL_DEFINE6(preadv2, compat_ulong_t, fd,

		const struct compat_iovec __user *,vec,

		const struct iovec __user *, vec,

		compat_ulong_t, vlen, u32, pos_low, u32, pos_high,

		rwf_t, flags)

{

	loff_t pos = ((loff_t)pos_high << 32) | pos_low;



	if (pos == -1)

		return do_compat_readv(fd, vec, vlen, flags);



	return do_compat_preadv64(fd, vec, vlen, pos, flags);

}



static size_t compat_writev(struct file *file,

			    const struct compat_iovec __user *vec,

			    unsigned long vlen, loff_t *pos, rwf_t flags)

{

	struct iovec iovstack[UIO_FASTIOV];

	struct iovec *iov = iovstack;

	struct iov_iter iter;

	ssize_t ret;



	ret = import_iovec(WRITE, (const struct iovec __user *)vec, vlen,

			   UIO_FASTIOV, &iov, &iter);

	if (ret >= 0) {

		file_start_write(file);

		ret = do_iter_write(file, &iter, pos, flags);

		file_end_write(file);

		kfree(iov);

	}

	if (ret > 0)

		add_wchar(current, ret);

	inc_syscw(current);

	return ret;

}



static size_t do_compat_writev(compat_ulong_t fd,

				  const struct compat_iovec __user* vec,

				  compat_ulong_t vlen, rwf_t flags)

{

	struct fd f = fdget_pos(fd);

	ssize_t ret;

	loff_t pos;



	if (!f.file)

		return -EBADF;

	pos = f.file->f_pos;

	ret = compat_writev(f.file, vec, vlen, &pos, flags);

	if (ret >= 0)

		f.file->f_pos = pos;

	fdput_pos(f);

	return ret;

		return do_readv(fd, vec, vlen, flags);

	return do_preadv(fd, vec, vlen, pos, flags);

}



COMPAT_SYSCALL_DEFINE3(writev, compat_ulong_t, fd,

		const struct compat_iovec __user *, vec,

		const struct iovec __user *, vec,

		compat_ulong_t, vlen)

{

	return do_compat_writev(fd, vec, vlen, 0);

}



static long do_compat_pwritev64(unsigned long fd,

				   const struct compat_iovec __user *vec,

				   unsigned long vlen, loff_t pos, rwf_t flags)

{

	struct fd f;

	ssize_t ret;



	if (pos < 0)

		return -EINVAL;

	f = fdget(fd);

	if (!f.file)

		return -EBADF;

	ret = -ESPIPE;

	if (f.file->f_mode & FMODE_PWRITE)

		ret = compat_writev(f.file, vec, vlen, &pos, flags);

	fdput(f);

	return ret;

	return do_writev(fd, vec, vlen, 0);

}



#ifdef __ARCH_WANT_COMPAT_SYS_PWRITEV64

COMPAT_SYSCALL_DEFINE4(pwritev64, unsigned long, fd,

		const struct compat_iovec __user *,vec,

		const struct iovec __user *, vec,

		unsigned long, vlen, loff_t, pos)

{

	return do_compat_pwritev64(fd, vec, vlen, pos, 0);

	return do_pwritev(fd, vec, vlen, pos, 0);

}

#endif



COMPAT_SYSCALL_DEFINE5(pwritev, compat_ulong_t, fd,

		const struct compat_iovec __user *,vec,

		const struct iovec __user *,vec,

		compat_ulong_t, vlen, u32, pos_low, u32, pos_high)

{

	loff_t pos = ((loff_t)pos_high << 32) | pos_low;



	return do_compat_pwritev64(fd, vec, vlen, pos, 0);

	return do_pwritev(fd, vec, vlen, pos, 0);

}



#ifdef __ARCH_WANT_COMPAT_SYS_PWRITEV64V2

COMPAT_SYSCALL_DEFINE5(pwritev64v2, unsigned long, fd,

		const struct compat_iovec __user *,vec,

		const struct iovec __user *, vec,

		unsigned long, vlen, loff_t, pos, rwf_t, flags)

{

	if (pos == -1)

		return do_compat_writev(fd, vec, vlen, flags);



	return do_compat_pwritev64(fd, vec, vlen, pos, flags);

		return do_writev(fd, vec, vlen, flags);

	return do_pwritev(fd, vec, vlen, pos, flags);

}

#endif



COMPAT_SYSCALL_DEFINE6(pwritev2, compat_ulong_t, fd,

		const struct compat_iovec __user *,vec,

		const struct iovec __user *,vec,

		compat_ulong_t, vlen, u32, pos_low, u32, pos_high, rwf_t, flags)

{

	loff_t pos = ((loff_t)pos_high << 32) | pos_low;



	if (pos == -1)

		return do_compat_writev(fd, vec, vlen, flags);



	return do_compat_pwritev64(fd, vec, vlen, pos, flags);

		return do_writev(fd, vec, vlen, flags);

	return do_pwritev(fd, vec, vlen, pos, flags);

}



#endif

#endif /* CONFIG_COMPAT */



static ssize_t do_sendfile(int out_fd, int in_fd, loff_t *ppos,

		  	   size_t count, loff_t max)

include/linux/compat.h

+10 −10
Original line number Diff line number Diff line
@@ -546,25 +546,25 @@ asmlinkage long compat_sys_getdents(unsigned int fd, 
/* fs/read_write.c */

asmlinkage long compat_sys_lseek(unsigned int, compat_off_t, unsigned int);

asmlinkage ssize_t compat_sys_readv(compat_ulong_t fd,

		const struct compat_iovec __user *vec, compat_ulong_t vlen);

		const struct iovec __user *vec, compat_ulong_t vlen);

asmlinkage ssize_t compat_sys_writev(compat_ulong_t fd,

		const struct compat_iovec __user *vec, compat_ulong_t vlen);

		const struct iovec __user *vec, compat_ulong_t vlen);

/* No generic prototype for pread64 and pwrite64 */

asmlinkage ssize_t compat_sys_preadv(compat_ulong_t fd,

		const struct compat_iovec __user *vec,

		const struct iovec __user *vec,

		compat_ulong_t vlen, u32 pos_low, u32 pos_high);

asmlinkage ssize_t compat_sys_pwritev(compat_ulong_t fd,

		const struct compat_iovec __user *vec,

		const struct iovec __user *vec,

		compat_ulong_t vlen, u32 pos_low, u32 pos_high);

#ifdef __ARCH_WANT_COMPAT_SYS_PREADV64

asmlinkage long compat_sys_preadv64(unsigned long fd,

		const struct compat_iovec __user *vec,

		const struct iovec __user *vec,

		unsigned long vlen, loff_t pos);

#endif



#ifdef __ARCH_WANT_COMPAT_SYS_PWRITEV64

asmlinkage long compat_sys_pwritev64(unsigned long fd,

		const struct compat_iovec __user *vec,

		const struct iovec __user *vec,

		unsigned long vlen, loff_t pos);

#endif
@@ -800,20 +800,20 @@ asmlinkage long compat_sys_execveat(int dfd, const char __user *filename, 
		     const compat_uptr_t __user *argv,

		     const compat_uptr_t __user *envp, int flags);

asmlinkage ssize_t compat_sys_preadv2(compat_ulong_t fd,

		const struct compat_iovec __user *vec,

		const struct iovec __user *vec,

		compat_ulong_t vlen, u32 pos_low, u32 pos_high, rwf_t flags);

asmlinkage ssize_t compat_sys_pwritev2(compat_ulong_t fd,

		const struct compat_iovec __user *vec,

		const struct iovec __user *vec,

		compat_ulong_t vlen, u32 pos_low, u32 pos_high, rwf_t flags);

#ifdef __ARCH_WANT_COMPAT_SYS_PREADV64V2

asmlinkage long  compat_sys_preadv64v2(unsigned long fd,

		const struct compat_iovec __user *vec,

		const struct iovec __user *vec,

		unsigned long vlen, loff_t pos, rwf_t flags);

#endif



#ifdef __ARCH_WANT_COMPAT_SYS_PWRITEV64V2

asmlinkage long compat_sys_pwritev64v2(unsigned long fd,

		const struct compat_iovec __user *vec,

		const struct iovec __user *vec,

		unsigned long vlen, loff_t pos, rwf_t flags);

#endif

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