Re: MO: opening for write in cdrom.c

From: Pascal Schmidt
Date: Tue Jan 27 2004 - 13:16:48 EST


[...]
> I'll make that change everywhere and then send an updated version.

Here's an updated version, both patches as one.

This solves the remaining problems (512 byte sector discs) and
rough edges (write-protect detection) with ATAPI MO support via
ide-cd/cdrom for me.


--- linux-2.6.2-rc1/include/linux/cdrom.h.orig Sun Jan 25 23:21:19 2004
+++ linux-2.6.2-rc1/include/linux/cdrom.h Mon Jan 26 18:46:54 2004
@@ -496,6 +496,7 @@ struct cdrom_generic_command
#define GPCMD_GET_MEDIA_STATUS 0xda

/* Mode page codes for mode sense/set */
+#define GPMODE_VENDOR_PAGE 0x00
#define GPMODE_R_W_ERROR_PAGE 0x01
#define GPMODE_WRITE_PARMS_PAGE 0x05
#define GPMODE_AUDIO_CTL_PAGE 0x0e
--- linux-2.6.2-rc1/drivers/cdrom/cdrom.c.orig Sat Jan 24 01:23:30 2004
+++ linux-2.6.2-rc1/drivers/cdrom/cdrom.c Tue Jan 27 18:49:02 2004
@@ -696,6 +696,35 @@ static int cdrom_mrw_open_write(struct c
return ret;
}

+static int mo_open_write(struct cdrom_device_info *cdi)
+{
+ struct cdrom_generic_command cgc;
+ char buffer[255];
+ int ret;
+
+ init_cdrom_command(&cgc, &buffer, 4, CGC_DATA_READ);
+ cgc.quiet = 1;
+
+ /*
+ * obtain write protect information as per
+ * drivers/scsi/sd.c:sd_read_write_protect_flag
+ */
+
+ ret = cdrom_mode_sense(cdi, &cgc, GPMODE_ALL_PAGES, 0);
+ if (ret)
+ ret = cdrom_mode_sense(cdi, &cgc, GPMODE_VENDOR_PAGE, 0);
+ if (ret) {
+ cgc.buflen = 255;
+ ret = cdrom_mode_sense(cdi, &cgc, GPMODE_ALL_PAGES, 0);
+ }
+
+ /* drive gave us no info, let the user go ahead */
+ if (ret)
+ return 0;
+
+ return buffer[3] & 0x80;
+}
+
/*
* returns 0 for ok to open write, non-0 to disallow
*/
@@ -707,11 +736,8 @@ static int cdrom_open_write(struct cdrom
ret = cdrom_mrw_open_write(cdi);
else if (CDROM_CAN(CDC_DVD_RAM))
ret = cdrom_dvdram_open_write(cdi);
- /*
- * needs to really check whether media is writeable
- */
else if (CDROM_CAN(CDC_MO_DRIVE))
- ret = 0;
+ ret = mo_open_write(cdi);

return ret;
}
--- linux-2.6.2-rc1/drivers/ide/ide-cd.c.orig Sat Jan 24 01:24:03 2004
+++ linux-2.6.2-rc1/drivers/ide/ide-cd.c Tue Jan 27 18:53:09 2004
@@ -294,10 +294,12 @@
* 4.60 Dec 17, 2003 - Add mt rainier support
* - Bump timeout for packet commands, matches sr
* - Odd stuff
+ * 4.61 Jan 22, 2004 - support hardware sector sizes other than 2kB,
+ * Pascal Schmidt <der.eremit@xxxxxxxx>
*
*************************************************************************/

-#define IDECD_VERSION "4.60"
+#define IDECD_VERSION "4.61"

#include <linux/config.h>
#include <linux/module.h>
@@ -1211,6 +1213,9 @@ static int cdrom_read_from_buffer (ide_d
{
struct cdrom_info *info = drive->driver_data;
struct request *rq = HWGROUP(drive)->rq;
+ unsigned short sectors_per_frame;
+
+ sectors_per_frame = queue_hardsect_size(drive->queue) >> SECTOR_BITS;

/* Can't do anything if there's no buffer. */
if (info->buffer == NULL) return 0;
@@ -1249,7 +1254,7 @@ static int cdrom_read_from_buffer (ide_d
will fail. I think that this will never happen, but let's be
paranoid and check. */
if (rq->current_nr_sectors < bio_cur_sectors(rq->bio) &&
- (rq->sector % SECTORS_PER_FRAME) != 0) {
+ (rq->sector % sectors_per_frame) != 0) {
printk("%s: cdrom_read_from_buffer: buffer botch (%ld)\n",
drive->name, (long)rq->sector);
cdrom_end_request(drive, 0);
@@ -1268,13 +1273,10 @@ static int cdrom_read_from_buffer (ide_d
static ide_startstop_t cdrom_start_read_continuation (ide_drive_t *drive)
{
struct request *rq = HWGROUP(drive)->rq;
- int nsect, sector, nframes, frame, nskip;
-
- /* Number of sectors to transfer. */
- nsect = rq->nr_sectors;
+ unsigned short sectors_per_frame;
+ int nskip;

- /* Starting sector. */
- sector = rq->sector;
+ sectors_per_frame = queue_hardsect_size(drive->queue) >> SECTOR_BITS;

/* If the requested sector doesn't start on a cdrom block boundary,
we must adjust the start of the transfer so that it does,
@@ -1283,31 +1285,19 @@ static ide_startstop_t cdrom_start_read_
of the buffer, it will mean that we're to skip a number
of sectors equal to the amount by which CURRENT_NR_SECTORS
is larger than the buffer size. */
- nskip = (sector % SECTORS_PER_FRAME);
+ nskip = (rq->sector % sectors_per_frame);
if (nskip > 0) {
/* Sanity check... */
if (rq->current_nr_sectors != bio_cur_sectors(rq->bio) &&
- (rq->sector % CD_FRAMESIZE != 0)) {
+ (rq->sector % sectors_per_frame != 0)) {
printk ("%s: cdrom_start_read_continuation: buffer botch (%u)\n",
drive->name, rq->current_nr_sectors);
cdrom_end_request(drive, 0);
return ide_stopped;
}
- sector -= nskip;
- nsect += nskip;
rq->current_nr_sectors += nskip;
}

- /* Convert from sectors to cdrom blocks, rounding up the transfer
- length if needed. */
- nframes = (nsect + SECTORS_PER_FRAME-1) / SECTORS_PER_FRAME;
- frame = sector / SECTORS_PER_FRAME;
-
- /* Largest number of frames was can transfer at once is 64k-1. For
- some drives we need to limit this even more. */
- nframes = MIN (nframes, (CDROM_CONFIG_FLAGS (drive)->limit_nframes) ?
- (65534 / CD_FRAMESIZE) : 65535);
-
/* Set up the command */
rq->timeout = ATAPI_WAIT_PC;

@@ -1346,13 +1336,11 @@ static ide_startstop_t cdrom_seek_intr (
static ide_startstop_t cdrom_start_seek_continuation (ide_drive_t *drive)
{
struct request *rq = HWGROUP(drive)->rq;
- int sector, frame, nskip;
+ unsigned short sectors_per_frame;
+ int frame;

- sector = rq->sector;
- nskip = (sector % SECTORS_PER_FRAME);
- if (nskip > 0)
- sector -= nskip;
- frame = sector / SECTORS_PER_FRAME;
+ sectors_per_frame = queue_hardsect_size(drive->queue) >> SECTOR_BITS;
+ frame = rq->sector / sectors_per_frame;

memset(rq->cmd, 0, sizeof(rq->cmd));
rq->cmd[0] = GPCMD_SEEK;
@@ -1396,6 +1384,9 @@ static ide_startstop_t cdrom_start_read
{
struct cdrom_info *info = drive->driver_data;
struct request *rq = HWGROUP(drive)->rq;
+ unsigned short sectors_per_frame;
+
+ sectors_per_frame = queue_hardsect_size(drive->queue) >> SECTOR_BITS;

/* We may be retrying this request after an error. Fix up
any weirdness which might be present in the request packet. */
@@ -1411,8 +1402,8 @@ static ide_startstop_t cdrom_start_read
info->nsectors_buffered = 0;

/* use dma, if possible. */
- if (drive->using_dma && (rq->sector % SECTORS_PER_FRAME == 0) &&
- (rq->nr_sectors % SECTORS_PER_FRAME == 0))
+ if (drive->using_dma && (rq->sector % sectors_per_frame == 0) &&
+ (rq->nr_sectors % sectors_per_frame == 0))
info->dma = 1;
else
info->dma = 0;
@@ -1950,11 +1941,15 @@ static ide_startstop_t cdrom_start_write
static ide_startstop_t cdrom_start_write(ide_drive_t *drive, struct request *rq)
{
struct cdrom_info *info = drive->driver_data;
+ unsigned short sectors_per_frame;
+
+ sectors_per_frame = queue_hardsect_size(drive->queue) >> SECTOR_BITS;

/*
- * writes *must* be 2kB frame aligned
+ * writes *must* be hardware frame aligned
*/
- if ((rq->nr_sectors & 3) || (rq->sector & 3)) {
+ if ((rq->nr_sectors & (sectors_per_frame - 1)) ||
+ (rq->sector & (sectors_per_frame - 1))) {
cdrom_end_request(drive, 0);
return ide_stopped;
}
@@ -1969,12 +1964,12 @@ static ide_startstop_t cdrom_start_write

info->nsectors_buffered = 0;

- /* use dma, if possible. we don't need to check more, since we
- * know that the transfer is always (at least!) 2KB aligned */
+ /* use dma, if possible. we don't need to check more, since we
+ * know that the transfer is always (at least!) frame aligned */
info->dma = drive->using_dma ? 1 : 0;
info->cmd = WRITE;

- /* Start sending the read request to the drive. */
+ /* Start sending the write request to the drive. */
return cdrom_start_packet_command(drive, 32768, cdrom_start_write_cont);
}

@@ -2209,6 +2204,7 @@ static int cdrom_eject(ide_drive_t *driv
}

static int cdrom_read_capacity(ide_drive_t *drive, unsigned long *capacity,
+ unsigned long *sectors_per_frame,
struct request_sense *sense)
{
struct {
@@ -2227,8 +2223,11 @@ static int cdrom_read_capacity(ide_drive
req.data_len = sizeof(capbuf);

stat = cdrom_queue_packet_command(drive, &req);
- if (stat == 0)
+ if (stat == 0) {
*capacity = 1 + be32_to_cpu(capbuf.lba);
+ *sectors_per_frame =
+ be32_to_cpu(capbuf.blocklen) >> SECTOR_BITS;
+ }

return stat;
}
@@ -2270,6 +2269,7 @@ static int cdrom_read_toc(ide_drive_t *d
struct atapi_toc_entry ent;
} ms_tmp;
long last_written;
+ unsigned long sectors_per_frame = SECTORS_PER_FRAME;

if (toc == NULL) {
/* Try to allocate space. */
@@ -2289,12 +2289,15 @@ static int cdrom_read_toc(ide_drive_t *d
if (CDROM_STATE_FLAGS(drive)->toc_valid)
return 0;

- /* Try to get the total cdrom capacity. */
- stat = cdrom_read_capacity(drive, &toc->capacity, sense);
+ /* Try to get the total cdrom capacity and sector size. */
+ stat = cdrom_read_capacity(drive, &toc->capacity, &sectors_per_frame,
+ sense);
if (stat)
toc->capacity = 0x1fffff;

- set_capacity(drive->disk, toc->capacity * SECTORS_PER_FRAME);
+ set_capacity(drive->disk, toc->capacity * sectors_per_frame);
+ blk_queue_hardsect_size(drive->queue,
+ sectors_per_frame << SECTOR_BITS);

/* First read just the header, so we know how long the TOC is. */
stat = cdrom_read_tocentry(drive, 0, 1, 0, (char *) &toc->hdr,
@@ -2406,7 +2409,7 @@ static int cdrom_read_toc(ide_drive_t *d
stat = cdrom_get_last_written(cdi, &last_written);
if (!stat && last_written) {
toc->capacity = last_written;
- set_capacity(drive->disk, toc->capacity * SECTORS_PER_FRAME);
+ set_capacity(drive->disk, toc->capacity * sectors_per_frame);
}

/* Remember that we've read this stuff. */
@@ -3306,12 +3309,12 @@ int ide_cdrom_setup (ide_drive_t *drive)
static
sector_t ide_cdrom_capacity (ide_drive_t *drive)
{
- unsigned long capacity;
+ unsigned long capacity, sectors_per_frame;

- if (cdrom_read_capacity(drive, &capacity, NULL))
+ if (cdrom_read_capacity(drive, &capacity, &sectors_per_frame, NULL))
return 0;

- return capacity * SECTORS_PER_FRAME;
+ return capacity * sectors_per_frame;
}

static


--
Ciao,
Pascal

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/