cdrom: gdrom: fix block I/O and capacity setting

GDROM_DATA_REG is a memory-mapped data register, but the driver uses outsw() and insw() only for this register. Replace this with MMIO accessors readsw() / writesw().

Before, it oopsed accessing the data register, as the io_port_base P2SEG gets added to the argument in outsw() / insw(), which leads to an unusable drive:

        BUG: unable to handle kernel paging request at 405f7080
        PC: [<8c28d5b4>] gdrom_spicommand+0x6c/0xb0

Signed-off-by Florian Fuchs <[email protected]>

---
v1->v2: Don't use helper functions with io.*_rep(), but writesw() and
readsw() local in the respective functions

v1: https://lore.kernel.org/linux-sh/[email protected]/

---
 drivers/cdrom/gdrom.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

drivers/cdrom/gdrom.c +3 -3

index 4ba4dd06cbf4..89938d9b2825 100644
@@ -198,7 +198,7 @@ static void gdrom_spicommand(void *spi_string, int 
 buflen)
 		gdrom_getsense(NULL);
 		return;
 	}
-	outsw(GDROM_DATA_REG, cmd, 6);
+	writesw((void __iomem *)GDROM_DATA_REG, cmd, 6);
 }
 

@@ -282,7 +282,7 @@ static int gdrom_readtoc_cmd(struct gdromtoc *toc, 
 int session)
 		err = -EINVAL;
 		goto cleanup_readtoc;
 	}
-	insw(GDROM_DATA_REG, toc, tocsize/2);
+	readsw((void __iomem *)GDROM_DATA_REG, toc, tocsize / 2);
 	if (gd.status & 0x01)
 		err = -EINVAL;

@@ -433,7 +433,7 @@ static int gdrom_getsense(short *bufstring)
 		GDROM_DEFAULT_TIMEOUT);
 	if (gd.pending)
 		goto cleanup_sense;
-	insw(GDROM_DATA_REG, &sense, sense_command->buflen/2);
+	readsw((void __iomem *)GDROM_DATA_REG, &sense, sense_command->buflen 
 / 2);
 	if (sense[1] & 40) {
 		pr_info("Drive not ready - command aborted\n");

drivers/cdrom/gdrom.c +1 -1

 		goto cleanup_sense;

@@ -612,7 +612,7 @@ static blk_status_t gdrom_readdisk_dma(struct 
 request *req)
 		cpu_relax();
 	gd.pending = 1;
 	gd.transfer = 1;
-	outsw(GDROM_DATA_REG, &read_command->cmd, 6);
+	writesw((void __iomem *)GDROM_DATA_REG, read_command->cmd, 6);
 	timeout = jiffies + HZ / 2;
 	/* Wait for any pending DMA to finish */

while (__raw_readb(GDROM_DMA_STATUS_REG) &&

Quoted 1 line · Florian Fuchs

Not tested this on real hardware but I can confirm it addresses the identified bug and is logically correct.

Update the gendisk capacity of the media. Without the capacity, the block reads fail before reaching the request queue, which prevented ISO9660 mounts. Refresh the capacity from the TOC leadout in gdrom_bdops_open() so it checks the inserted media.

Signed-off-by Florian Fuchs <[email protected]>

---
v1->v2: no change for gdrom_update_capacity(), but for
gdrom_bdops_open(): handle the failure case when gdrom_update_capacity() fails but previous cdrom_open()
succeeded,
to cleanup the successful cdrom_open() with cdrom_release()

v1: https://lore.kernel.org/linux-sh/[email protected]/

---
 drivers/cdrom/gdrom.c | 25 +++++++++++++++++++++++++
 1 file changed, 25 insertions(+)

drivers/cdrom/gdrom.c +25 -0

index 89938d9b2825..fb95288fad72 100644
@@ -474,6 +474,25 @@ static const struct cdrom_device_ops gdrom_ops = {
 				  CDC_RESET | CDC_DRIVE_STATUS | CDC_CD_R,
 };
 
+static int gdrom_update_capacity(void)
+{
+	sector_t cap;
+	int ret;
+
+	if (gdrom_drivestatus(gd.cd_info, CDSL_CURRENT) != CDS_DISC_OK) {
+		set_capacity(gd.disk, 0);
+		return -ENOMEDIUM;
+	}
+	ret = gdrom_readtoc_cmd(gd.toc, 0);
+	if (ret) {
+		set_capacity(gd.disk, 0);
+		return ret;
+	}
+	cap = (sector_t)get_entry_lba(gd.toc->leadout) * GD_TO_BLK;
+	set_capacity(gd.disk, cap);
+	return 0;
+}
+
 static int gdrom_bdops_open(struct gendisk *disk, blk_mode_t mode)
 {
 	int ret;

@@ -482,6 +501,12 @@ static int gdrom_bdops_open(struct gendisk *disk, 
 blk_mode_t mode)
 
 	mutex_lock(&gdrom_mutex);
 	ret = cdrom_open(gd.cd_info, mode);
+	if (ret)
+		goto out;
+	ret = gdrom_update_capacity();
+	if (ret)
+		cdrom_release(gd.cd_info);
+out:
 	mutex_unlock(&gdrom_mutex);
 	return ret;

}