[PATCH v2] scsi: fix disk capacity too small by one sector

[Julius Lehmann]

SCSI READ CAPACITY reports the address of the last block and the block
size. The total number of blocks is thus last block address plus one.

This also fixes the corresponding test case.

---
This patch fixes the disk size reported by scsi. Up until now, the reported disk size is too small by one sector. Read/Write operations on other sectors have not been affected. Trying to partition scsi backed storage via ums has resulted in "storage too small" errors.

doc: https://linux.die.net/man/8/sg_readcap

Signed-off-by: Julius Lehmann <lehmanju at devpi.de>
---
Changes in v2:
- fixed corresponding test case
- Link to v1: https://lore.kernel.org/r/20241014-fix-scsi-disksize-v1-1-0edb9959b580@devpi.de
---
 drivers/scsi/scsi.c | 2 ++
 test/boot/bootdev.c | 2 +-
 2 files changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/scsi/scsi.c b/drivers/scsi/scsi.c
index 51cacf3479236be6c6ea3e7d15b87e03f10e7f3a..bcdeda95ed1514119057cc67974fec465cf5672c 100644
--- a/drivers/scsi/scsi.c
+++ b/drivers/scsi/scsi.c
@@ -309,6 +309,7 @@ static int scsi_read_capacity(struct udevice *dev, struct scsi_cmd *pccb,
 			 ((unsigned long)pccb->pdata[5] << 16) |
 			 ((unsigned long)pccb->pdata[6] << 8)  |
 			 ((unsigned long)pccb->pdata[7]);
+		*capacity += 1;
 		return 0;
 	}
 
@@ -332,6 +333,7 @@ static int scsi_read_capacity(struct udevice *dev, struct scsi_cmd *pccb,
 		    ((uint64_t)pccb->pdata[5] << 16) |
 		    ((uint64_t)pccb->pdata[6] << 8)  |
 		    ((uint64_t)pccb->pdata[7]);
+	*capacity += 1;
 
 	*blksz = ((uint64_t)pccb->pdata[8]  << 56) |
 		 ((uint64_t)pccb->pdata[9]  << 48) |
diff --git a/test/boot/bootdev.c b/test/boot/bootdev.c
index c635d06ec25d4bf274099f153648d34f5a845436..bc632a3d14124f5f821c4625e5b29b7d352f7161 100644
--- a/test/boot/bootdev.c
+++ b/test/boot/bootdev.c
@@ -621,7 +621,7 @@ static int bootdev_test_next_label(struct unit_test_state *uts)
 	ut_assertok(bootdev_next_label(&iter, &dev, &mflags));
 	ut_assert_nextline("scanning bus for devices...");
 	ut_assert_skip_to_line(
-		"            Capacity: 1.9 MB = 0.0 GB (4095 x 512)");
+		"            Capacity: 2.0 MB = 0.0 GB (4096 x 512)");
 	ut_assert_console_end();
 	ut_assertnonnull(dev);
 	ut_asserteq_str("scsi.id0lun0.bootdev", dev->name);

---
base-commit: 29e5dbc55c64c6450f066c55a5bc48bd1717aa1b
change-id: 20241014-fix-scsi-disksize-d73a017cadf4

Best regards,
-- 
Julius Lehmann <lehmanju at devpi.de>