On 03/29/2016 01:06 AM, Hannes Reinecke wrote:
> in sd_read_capacity() the sdkp->capacity field changes its meaning:
> after the call to read_capacity_XX() it carries the _unscaled_ values,
> making the comparison between the original value and the new value
> always false for drives with a sector size != 512.
>
> Signed-off-by: Hannes Reinecke <hare@xxxxxxx>
> ---
> drivers/scsi/sd.c | 69 +++++++++++++++++++++++++++++++------------------------
> 1 file changed, 39 insertions(+), 30 deletions(-)
>
> diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c
> index 5a5457a..0afe113 100644
> --- a/drivers/scsi/sd.c
> +++ b/drivers/scsi/sd.c
> @@ -2046,7 +2046,7 @@ static void read_capacity_error(struct scsi_disk *sdkp, struct scsi_device *sdp,
> #define READ_CAPACITY_RETRIES_ON_RESET 10
>
> static int read_capacity_16(struct scsi_disk *sdkp, struct scsi_device *sdp,
> - unsigned char *buffer)
> + unsigned char *buffer, u64 *capacity)
> {
> unsigned char cmd[16];
> struct scsi_sense_hdr sshdr;
> @@ -2054,8 +2054,8 @@ static int read_capacity_16(struct scsi_disk *sdkp, struct scsi_device *sdp,
> int the_result;
> int retries = 3, reset_retries = READ_CAPACITY_RETRIES_ON_RESET;
> unsigned int alignment;
> - unsigned long long lba;
> - unsigned sector_size;
> + u64 lba;
> + u32 sector_size;
>
> if (sdp->no_read_capacity_16)
> return -EINVAL;
> @@ -2114,7 +2114,7 @@ static int read_capacity_16(struct scsi_disk *sdkp, struct scsi_device *sdp,
> sd_printk(KERN_ERR, sdkp, "Too big for this kernel. Use a "
> "kernel compiled with support for large block "
> "devices.\n");
> - sdkp->capacity = 0;
> + *capacity = 0;
> return -EOVERFLOW;
> }
>
> @@ -2137,20 +2137,20 @@ static int read_capacity_16(struct scsi_disk *sdkp, struct scsi_device *sdp,
> sd_config_discard(sdkp, SD_LBP_WS16);
> }
>
> - sdkp->capacity = lba + 1;
> + *capacity = lba + 1;
> return sector_size;
> }
>
> static int read_capacity_10(struct scsi_disk *sdkp, struct scsi_device *sdp,
> - unsigned char *buffer)
> + unsigned char *buffer, u64 *capacity)
> {
> unsigned char cmd[16];
> struct scsi_sense_hdr sshdr;
> int sense_valid = 0;
> int the_result;
> int retries = 3, reset_retries = READ_CAPACITY_RETRIES_ON_RESET;
> - sector_t lba;
> - unsigned sector_size;
> + u32 lba;
> + u32 sector_size;
>
> do {
> cmd[0] = READ_CAPACITY;
> @@ -2191,7 +2191,7 @@ static int read_capacity_10(struct scsi_disk *sdkp, struct scsi_device *sdp,
> /* Some buggy (usb cardreader) devices return an lba of
> 0xffffffff when the want to report a size of 0 (with
> which they really mean no media is present) */
> - sdkp->capacity = 0;
> + *capacity = 0;
> sdkp->physical_block_size = sector_size;
> return sector_size;
> }
> @@ -2200,11 +2200,11 @@ static int read_capacity_10(struct scsi_disk *sdkp, struct scsi_device *sdp,
> sd_printk(KERN_ERR, sdkp, "Too big for this kernel. Use a "
> "kernel compiled with support for large block "
> "devices.\n");
> - sdkp->capacity = 0;
> + *capacity = 0;
> return -EOVERFLOW;
> }
>
> - sdkp->capacity = lba + 1;
> + *capacity = (u64)lba + 1;
> sdkp->physical_block_size = sector_size;
> return sector_size;
> }
> @@ -2230,34 +2230,38 @@ sd_read_capacity(struct scsi_disk *sdkp, unsigned char *buffer)
> {
> int sector_size;
> struct scsi_device *sdp = sdkp->device;
> - sector_t old_capacity = sdkp->capacity;
> + u64 old_capacity = sdkp->capacity, new_capacity;
>
> if (sd_try_rc16_first(sdp)) {
> - sector_size = read_capacity_16(sdkp, sdp, buffer);
> + sector_size = read_capacity_16(sdkp, sdp, buffer,
> + &new_capacity);
> if (sector_size == -EOVERFLOW)
> goto got_data;
> if (sector_size == -ENODEV)
> return;
> if (sector_size < 0)
> - sector_size = read_capacity_10(sdkp, sdp, buffer);
> + sector_size = read_capacity_10(sdkp, sdp, buffer,
> + &new_capacity);
> if (sector_size < 0)
> return;
> } else {
> - sector_size = read_capacity_10(sdkp, sdp, buffer);
> + sector_size = read_capacity_10(sdkp, sdp, buffer,
> + &new_capacity);
> if (sector_size == -EOVERFLOW)
> goto got_data;
> if (sector_size < 0)
> return;
> if ((sizeof(sdkp->capacity) > 4) &&
> - (sdkp->capacity > 0xffffffffULL)) {
> + (new_capacity > 0xffffffffULL)) {
> int old_sector_size = sector_size;
> sd_printk(KERN_NOTICE, sdkp, "Very big device. "
> "Trying to use READ CAPACITY(16).\n");
> - sector_size = read_capacity_16(sdkp, sdp, buffer);
> + sector_size = read_capacity_16(sdkp, sdp, buffer,
> + &new_capacity);
> if (sector_size < 0) {
> sd_printk(KERN_NOTICE, sdkp,
> "Using 0xffffffff as device size\n");
> - sdkp->capacity = 1 + (sector_t) 0xffffffff;
> + new_capacity = 1 + (u64) 0xffffffff;
> sector_size = old_sector_size;
> goto got_data;
> }
> @@ -2275,11 +2279,11 @@ sd_read_capacity(struct scsi_disk *sdkp, unsigned char *buffer)
> * the capacity.
> */
> if (sdp->fix_capacity ||
> - (sdp->guess_capacity && (sdkp->capacity & 0x01))) {
> + (sdp->guess_capacity && (new_capacity & 0x01))) {
> sd_printk(KERN_INFO, sdkp, "Adjusting the sector count "
> "from its reported value: %llu\n",
> - (unsigned long long) sdkp->capacity);
> - --sdkp->capacity;
> + (unsigned long long) new_capacity);
> + --new_capacity;
> }
>
> got_data:
> @@ -2301,7 +2305,7 @@ got_data:
> * would be relatively trivial to set the thing up.
> * For this reason, we leave the thing in the table.
> */
> - sdkp->capacity = 0;
> + new_capacity = 0;
> /*
> * set a bogus sector size so the normal read/write
> * logic in the block layer will eventually refuse any
> @@ -2312,6 +2316,19 @@ got_data:
> }
> blk_queue_logical_block_size(sdp->request_queue, sector_size);
>
> + /*
> + * Note: up to this point new_capacity carries the
> + * _unscaled_ capacity. So rescale capacity to 512-byte units.
> + */
> + if (sector_size == 4096)
> + sdkp->capacity = new_capacity << 3;
> + else if (sector_size == 2048)
> + sdkp->capacity = new_capacity << 2;
> + else if (sector_size == 1024)
> + sdkp->capacity = new_capacity << 1;
> + else
> + sdkp->capacity = new_capacity;
> +
> {
> char cap_str_2[10], cap_str_10[10];
>
> @@ -2337,14 +2354,6 @@ got_data:
> if (sdkp->capacity > 0xffffffff)
> sdp->use_16_for_rw = 1;
>
> - /* Rescale capacity to 512-byte units */
> - if (sector_size == 4096)
> - sdkp->capacity <<= 3;
> - else if (sector_size == 2048)
> - sdkp->capacity <<= 2;
> - else if (sector_size == 1024)
> - sdkp->capacity <<= 1;
> -
> blk_queue_physical_block_size(sdp->request_queue,
> sdkp->physical_block_size);
> sdkp->device->sector_size = sector_size;
>
Reviewed-by: Lee Duncan <lduncan@xxxxxxxx>
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