Add sendfile64 syscall to generic code and i386.

arch/i386/kernel/entry.S

@@ -716,6 +716,7 @@ ENTRY(sys_call_table)
 	.long SYMBOL_NAME(sys_lremovexattr)
 	.long SYMBOL_NAME(sys_fremovexattr)
 	.long SYMBOL_NAME(sys_tkill)
+	.long SYMBOL_NAME(sys_sendfile64)
 
 	.rept NR_syscalls-(.-sys_call_table)/4
 		.long SYMBOL_NAME(sys_ni_syscall)

include/asm-i386/unistd.h

@@ -243,6 +243,7 @@
 #define __NR_lremovexattr	236
 #define __NR_fremovexattr	237
 #define __NR_tkill		238
+#define __NR_sendfile64		239
 
 /* user-visible error numbers are in the range -1 - -124: see <asm-i386/errno.h> */
 

mm/filemap.c

@@ -1715,7 +1715,7 @@ static int file_send_actor(read_descriptor_t * desc, struct page *page, unsigned
 	return written;
 }
 
-asmlinkage ssize_t sys_sendfile(int out_fd, int in_fd, off_t *offset, size_t count)
+static ssize_t common_sendfile(int out_fd, int in_fd, loff_t *offset, size_t count)
 {
 	ssize_t retval;
 	struct file * in_file, * out_file;
@@ -1760,27 +1760,19 @@ asmlinkage ssize_t sys_sendfile(int out_fd, int in_fd, off_t *offset, size_t cou
 	retval = 0;
 	if (count) {
 		read_descriptor_t desc;
-		loff_t pos = 0, *ppos;
-
-		retval = -EFAULT;
-		ppos = &in_file->f_pos;
-		if (offset) {
-			if (get_user(pos, offset))
-				goto fput_out;
-			ppos = &pos;
-		}
+
+		if (!offset)
+			offset = &in_file->f_pos;
 
 		desc.written = 0;
 		desc.count = count;
 		desc.buf = (char *) out_file;
 		desc.error = 0;
-		do_generic_file_read(in_file, ppos, &desc, file_send_actor);
+		do_generic_file_read(in_file, offset, &desc, file_send_actor);
 
 		retval = desc.written;
 		if (!retval)
 			retval = desc.error;
-		if (offset)
-			put_user(pos, offset);
 	}
 
 fput_out:
@@ -1791,6 +1783,38 @@ asmlinkage ssize_t sys_sendfile(int out_fd, int in_fd, off_t *offset, size_t cou
 	return retval;
 }
 
+asmlinkage ssize_t sys_sendfile(int out_fd, int in_fd, off_t *offset, size_t count)
+{
+	loff_t pos, *ppos = NULL;
+	ssize_t ret;
+	if (offset) {
+		off_t off;
+		if (unlikely(get_user(off, offset)))
+			return -EFAULT;
+		pos = off;
+		ppos = &pos;
+	}
+	ret = common_sendfile(out_fd, in_fd, ppos, count);
+	if (offset)
+		put_user((off_t)pos, offset);
+	return ret;
+}
+
+asmlinkage ssize_t sys_sendfile64(int out_fd, int in_fd, loff_t *offset, size_t count)
+{
+	loff_t pos, *ppos = NULL;
+	ssize_t ret;
+	if (offset) {
+		if (unlikely(copy_from_user(&pos, offset, sizeof(loff_t))))
+			return -EFAULT;
+		ppos = &pos;
+	}
+	ret = common_sendfile(out_fd, in_fd, ppos, count);
+	if (offset)
+		put_user(pos, offset);
+	return ret;
+}
+
 static ssize_t do_readahead(struct file *file, unsigned long index, unsigned long nr)
 {
 	struct address_space *mapping = file->f_dentry->d_inode->i_mapping;