1 files changed, 92 insertions, 94 deletions

diff --git a/drivers/scsi/scsicam.c b/drivers/scsi/scsicam.c
index e969138051c7..682cf08ab041 100644
--- a/drivers/scsi/scsicam.c
+++ b/drivers/scsi/scsicam.c
@@ -17,14 +17,11 @@
 #include <linux/genhd.h>
 #include <linux/kernel.h>
 #include <linux/blkdev.h>
+#include <linux/msdos_partition.h>
 #include <asm/unaligned.h>
 
 #include <scsi/scsicam.h>
 
-
-static int setsize(unsigned long capacity, unsigned int *cyls, unsigned int *hds,
-		   unsigned int *secs);
-
 /**
  * scsi_bios_ptable - Read PC partition table out of first sector of device.
  * @dev: from this device
@@ -35,105 +32,48 @@ static int setsize(unsigned long capacity, unsigned int *cyls, unsigned int *hds
  */
 unsigned char *scsi_bios_ptable(struct block_device *dev)
 {
-	unsigned char *res = kmalloc(66, GFP_KERNEL);
-	if (res) {
-		struct block_device *bdev = dev->bd_contains;
-		Sector sect;
-		void *data = read_dev_sector(bdev, 0, &sect);
-		if (data) {
-			memcpy(res, data + 0x1be, 66);
-			put_dev_sector(sect);
-		} else {
-			kfree(res);
-			res = NULL;
-		}
-	}
-	return res;
-}
-EXPORT_SYMBOL(scsi_bios_ptable);
-
-/**
- * scsicam_bios_param - Determine geometry of a disk in cylinders/heads/sectors.
- * @bdev: which device
- * @capacity: size of the disk in sectors
- * @ip: return value: ip[0]=heads, ip[1]=sectors, ip[2]=cylinders
- *
- * Description : determine the BIOS mapping/geometry used for a drive in a
- *      SCSI-CAM system, storing the results in ip as required
- *      by the HDIO_GETGEO ioctl().
- *
- * Returns : -1 on failure, 0 on success.
- */
-
-int scsicam_bios_param(struct block_device *bdev, sector_t capacity, int *ip)
-{
-	unsigned char *p;
-	u64 capacity64 = capacity;	/* Suppress gcc warning */
-	int ret;
-
-	p = scsi_bios_ptable(bdev);
-	if (!p)
-		return -1;
-
-	/* try to infer mapping from partition table */
-	ret = scsi_partsize(p, (unsigned long)capacity, (unsigned int *)ip + 2,
-			       (unsigned int *)ip + 0, (unsigned int *)ip + 1);
-	kfree(p);
-
-	if (ret == -1 && capacity64 < (1ULL << 32)) {
-		/* pick some standard mapping with at most 1024 cylinders,
-		   and at most 62 sectors per track - this works up to
-		   7905 MB */
-		ret = setsize((unsigned long)capacity, (unsigned int *)ip + 2,
-		       (unsigned int *)ip + 0, (unsigned int *)ip + 1);
-	}
-
-	/* if something went wrong, then apparently we have to return
-	   a geometry with more than 1024 cylinders */
-	if (ret || ip[0] > 255 || ip[1] > 63) {
-		if ((capacity >> 11) > 65534) {
-			ip[0] = 255;
-			ip[1] = 63;
-		} else {
-			ip[0] = 64;
-			ip[1] = 32;
-		}
+	struct address_space *mapping = dev->bd_contains->bd_inode->i_mapping;
+	unsigned char *res = NULL;
+	struct page *page;
 
-		if (capacity > 65535*63*255)
-			ip[2] = 65535;
-		else
-			ip[2] = (unsigned long)capacity / (ip[0] * ip[1]);
-	}
+	page = read_mapping_page(mapping, 0, NULL);
+	if (IS_ERR(page))
+		return NULL;
 
-	return 0;
+	if (!PageError(page))
+		res = kmemdup(page_address(page) + 0x1be, 66, GFP_KERNEL);
+	put_page(page);
+	return res;
 }
-EXPORT_SYMBOL(scsicam_bios_param);
+EXPORT_SYMBOL(scsi_bios_ptable);
 
 /**
  * scsi_partsize - Parse cylinders/heads/sectors from PC partition table
- * @buf: partition table, see scsi_bios_ptable()
+ * @bdev: block device to parse
  * @capacity: size of the disk in sectors
- * @cyls: put cylinders here
- * @hds: put heads here
- * @secs: put sectors here
+ * @geom: output in form of [hds, cylinders, sectors]
  *
  * Determine the BIOS mapping/geometry used to create the partition
- * table, storing the results in @cyls, @hds, and @secs
+ * table, storing the results in @geom.
  *
- * Returns: -1 on failure, 0 on success.
+ * Returns: %false on failure, %true on success.
  */
-
-int scsi_partsize(unsigned char *buf, unsigned long capacity,
-	       unsigned int *cyls, unsigned int *hds, unsigned int *secs)
+bool scsi_partsize(struct block_device *bdev, sector_t capacity, int geom[3])
 {
-	struct partition *p = (struct partition *)buf, *largest = NULL;
-	int i, largest_cyl;
 	int cyl, ext_cyl, end_head, end_cyl, end_sector;
 	unsigned int logical_end, physical_end, ext_physical_end;
+	struct msdos_partition *p, *largest = NULL;
+	void *buf;
+	int ret = false;
 
+	buf = scsi_bios_ptable(bdev);
+	if (!buf)
+		return false;
 
 	if (*(unsigned short *) (buf + 64) == 0xAA55) {
-		for (largest_cyl = -1, i = 0; i < 4; ++i, ++p) {
+		int largest_cyl = -1, i;
+
+		for (i = 0, p = buf; i < 4; i++, p++) {
 			if (!p->sys_ind)
 				continue;
 #ifdef DEBUG
@@ -153,7 +93,7 @@ int scsi_partsize(unsigned char *buf, unsigned long capacity,
 		end_sector = largest->end_sector & 0x3f;
 
 		if (end_head + 1 == 0 || end_sector == 0)
-			return -1;
+			goto out_free_buf;
 
 #ifdef DEBUG
 		printk("scsicam_bios_param : end at h = %d, c = %d, s = %d\n",
@@ -178,19 +118,24 @@ int scsi_partsize(unsigned char *buf, unsigned long capacity,
 		  ,logical_end, physical_end, ext_physical_end, ext_cyl);
 #endif
 
-		if ((logical_end == physical_end) ||
-		  (end_cyl == 1023 && ext_physical_end == logical_end)) {
-			*secs = end_sector;
-			*hds = end_head + 1;
-			*cyls = capacity / ((end_head + 1) * end_sector);
-			return 0;
+		if (logical_end == physical_end ||
+		    (end_cyl == 1023 && ext_physical_end == logical_end)) {
+			geom[0] = end_head + 1;
+			geom[1] = end_sector;
+			geom[2] = (unsigned long)capacity /
+				((end_head + 1) * end_sector);
+			ret = true;
+			goto out_free_buf;
 		}
 #ifdef DEBUG
 		printk("scsicam_bios_param : logical (%u) != physical (%u)\n",
 		       logical_end, physical_end);
 #endif
 	}
-	return -1;
+
+out_free_buf:
+	kfree(buf);
+	return ret;
 }
 EXPORT_SYMBOL(scsi_partsize);
 
@@ -258,3 +203,56 @@ static int setsize(unsigned long capacity, unsigned int *cyls, unsigned int *hds
 	*hds = (unsigned int) heads;
 	return (rv);
 }
+
+/**
+ * scsicam_bios_param - Determine geometry of a disk in cylinders/heads/sectors.
+ * @bdev: which device
+ * @capacity: size of the disk in sectors
+ * @ip: return value: ip[0]=heads, ip[1]=sectors, ip[2]=cylinders
+ *
+ * Description : determine the BIOS mapping/geometry used for a drive in a
+ *      SCSI-CAM system, storing the results in ip as required
+ *      by the HDIO_GETGEO ioctl().
+ *
+ * Returns : -1 on failure, 0 on success.
+ */
+int scsicam_bios_param(struct block_device *bdev, sector_t capacity, int *ip)
+{
+	u64 capacity64 = capacity;	/* Suppress gcc warning */
+	int ret = 0;
+
+	/* try to infer mapping from partition table */
+	if (scsi_partsize(bdev, capacity, ip))
+		return 0;
+
+	if (capacity64 < (1ULL << 32)) {
+		/*
+		 * Pick some standard mapping with at most 1024 cylinders, and
+		 * at most 62 sectors per track - this works up to 7905 MB.
+		 */
+		ret = setsize((unsigned long)capacity, (unsigned int *)ip + 2,
+		       (unsigned int *)ip + 0, (unsigned int *)ip + 1);
+	}
+
+	/*
+	 * If something went wrong, then apparently we have to return a geometry
+	 * with more than 1024 cylinders.
+	 */
+	if (ret || ip[0] > 255 || ip[1] > 63) {
+		if ((capacity >> 11) > 65534) {
+			ip[0] = 255;
+			ip[1] = 63;
+		} else {
+			ip[0] = 64;
+			ip[1] = 32;
+		}
+
+		if (capacity > 65535*63*255)
+			ip[2] = 65535;
+		else
+			ip[2] = (unsigned long)capacity / (ip[0] * ip[1]);
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL(scsicam_bios_param);