Remove 'type' argument from access_ok() function

Nobody has actually used the type (VERIFY_READ vs VERIFY_WRITE) argument
of the user address range verification function since we got rid of the
old racy i386-only code to walk page tables by hand.

It existed because the original 80386 would not honor the write protect
bit when in kernel mode, so you had to do COW by hand before doing any
user access.  But we haven't supported that in a long time, and these
days the 'type' argument is a purely historical artifact.

A discussion about extending 'user_access_begin()' to do the range
checking resulted this patch, because there is no way we're going to
move the old VERIFY_xyz interface to that model.  And it's best done at
the end of the merge window when I've done most of my merges, so let's
just get this done once and for all.

This patch was mostly done with a sed-script, with manual fix-ups for
the cases that weren't of the trivial 'access_ok(VERIFY_xyz' form.

There were a couple of notable cases:

 - csky still had the old "verify_area()" name as an alias.

 - the iter_iov code had magical hardcoded knowledge of the actual
   values of VERIFY_{READ,WRITE} (not that they mattered, since nothing
   really used it)

 - microblaze used the type argument for a debug printout

but other than those oddities this should be a total no-op patch.

I tried to fix up all architectures, did fairly extensive grepping for
access_ok() uses, and the changes are trivial, but I may have missed
something.  Any missed conversion should be trivially fixable, though.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

3 files changed, 10 insertions, 12 deletions

diff --git a/drivers/scsi/pmcraid.c b/drivers/scsi/pmcraid.c
index 7c4673308f5b..e338d7a4f571 100644
--- a/drivers/scsi/pmcraid.c
+++ b/drivers/scsi/pmcraid.c
@@ -3600,7 +3600,7 @@ static long pmcraid_ioctl_passthrough(
 	u32 ioasc;
 	int request_size;
 	int buffer_size;
-	u8 access, direction;
+	u8 direction;
 	int rc = 0;
 
 	/* If IOA reset is in progress, wait 10 secs for reset to complete */
@@ -3649,10 +3649,8 @@ static long pmcraid_ioctl_passthrough(
 	request_size = le32_to_cpu(buffer->ioarcb.data_transfer_length);
 
 	if (buffer->ioarcb.request_flags0 & TRANSFER_DIR_WRITE) {
-		access = VERIFY_READ;
 		direction = DMA_TO_DEVICE;
 	} else {
-		access = VERIFY_WRITE;
 		direction = DMA_FROM_DEVICE;
 	}
 
diff --git a/drivers/scsi/scsi_ioctl.c b/drivers/scsi/scsi_ioctl.c
index cc30fccc1a2e..840d96fe81bc 100644
--- a/drivers/scsi/scsi_ioctl.c
+++ b/drivers/scsi/scsi_ioctl.c
@@ -221,7 +221,7 @@ int scsi_ioctl(struct scsi_device *sdev, int cmd, void __user *arg)
 
 	switch (cmd) {
 	case SCSI_IOCTL_GET_IDLUN:
-		if (!access_ok(VERIFY_WRITE, arg, sizeof(struct scsi_idlun)))
+		if (!access_ok(arg, sizeof(struct scsi_idlun)))
 			return -EFAULT;
 
 		__put_user((sdev->id & 0xff)
diff --git a/drivers/scsi/sg.c b/drivers/scsi/sg.c
index 4e27460ec926..d3f15319b9b3 100644
--- a/drivers/scsi/sg.c
+++ b/drivers/scsi/sg.c
@@ -434,7 +434,7 @@ sg_read(struct file *filp, char __user *buf, size_t count, loff_t * ppos)
 	SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
 				      "sg_read: count=%d\n", (int) count));
 
-	if (!access_ok(VERIFY_WRITE, buf, count))
+	if (!access_ok(buf, count))
 		return -EFAULT;
 	if (sfp->force_packid && (count >= SZ_SG_HEADER)) {
 		old_hdr = kmalloc(SZ_SG_HEADER, GFP_KERNEL);
@@ -632,7 +632,7 @@ sg_write(struct file *filp, const char __user *buf, size_t count, loff_t * ppos)
 	      scsi_block_when_processing_errors(sdp->device)))
 		return -ENXIO;
 
-	if (!access_ok(VERIFY_READ, buf, count))
+	if (!access_ok(buf, count))
 		return -EFAULT;	/* protects following copy_from_user()s + get_user()s */
 	if (count < SZ_SG_HEADER)
 		return -EIO;
@@ -729,7 +729,7 @@ sg_new_write(Sg_fd *sfp, struct file *file, const char __user *buf,
 
 	if (count < SZ_SG_IO_HDR)
 		return -EINVAL;
-	if (!access_ok(VERIFY_READ, buf, count))
+	if (!access_ok(buf, count))
 		return -EFAULT; /* protects following copy_from_user()s + get_user()s */
 
 	sfp->cmd_q = 1;	/* when sg_io_hdr seen, set command queuing on */
@@ -768,7 +768,7 @@ sg_new_write(Sg_fd *sfp, struct file *file, const char __user *buf,
 		sg_remove_request(sfp, srp);
 		return -EMSGSIZE;
 	}
-	if (!access_ok(VERIFY_READ, hp->cmdp, hp->cmd_len)) {
+	if (!access_ok(hp->cmdp, hp->cmd_len)) {
 		sg_remove_request(sfp, srp);
 		return -EFAULT;	/* protects following copy_from_user()s + get_user()s */
 	}
@@ -922,7 +922,7 @@ sg_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg)
 			return -ENODEV;
 		if (!scsi_block_when_processing_errors(sdp->device))
 			return -ENXIO;
-		if (!access_ok(VERIFY_WRITE, p, SZ_SG_IO_HDR))
+		if (!access_ok(p, SZ_SG_IO_HDR))
 			return -EFAULT;
 		result = sg_new_write(sfp, filp, p, SZ_SG_IO_HDR,
 				 1, read_only, 1, &srp);
@@ -968,7 +968,7 @@ sg_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg)
 	case SG_GET_LOW_DMA:
 		return put_user((int) sdp->device->host->unchecked_isa_dma, ip);
 	case SG_GET_SCSI_ID:
-		if (!access_ok(VERIFY_WRITE, p, sizeof (sg_scsi_id_t)))
+		if (!access_ok(p, sizeof (sg_scsi_id_t)))
 			return -EFAULT;
 		else {
 			sg_scsi_id_t __user *sg_idp = p;
@@ -997,7 +997,7 @@ sg_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg)
 		sfp->force_packid = val ? 1 : 0;
 		return 0;
 	case SG_GET_PACK_ID:
-		if (!access_ok(VERIFY_WRITE, ip, sizeof (int)))
+		if (!access_ok(ip, sizeof (int)))
 			return -EFAULT;
 		read_lock_irqsave(&sfp->rq_list_lock, iflags);
 		list_for_each_entry(srp, &sfp->rq_list, entry) {
@@ -1078,7 +1078,7 @@ sg_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg)
 		val = (sdp->device ? 1 : 0);
 		return put_user(val, ip);
 	case SG_GET_REQUEST_TABLE:
-		if (!access_ok(VERIFY_WRITE, p, SZ_SG_REQ_INFO * SG_MAX_QUEUE))
+		if (!access_ok(p, SZ_SG_REQ_INFO * SG_MAX_QUEUE))
 			return -EFAULT;
 		else {
 			sg_req_info_t *rinfo;