Christoph?
It was reported that some devices report an OPTIMAL TRANSFER LENGTH of 0xFFFF blocks. That looks bogus, especially for a device with a 4096-byte physical block size.
Ignore OPTIMAL TRANSFER LENGTH if it is not a multiple of the device's reported physical block size.
To make the sanity checking conditionals more readable--and to facilitate printing warnings--relocate the checking to a helper function. No functional change aside from the printks.
Cc: stable@vger.kernel.org Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=199759 Reported-by: Christoph Anton Mitterer calestyo@scientia.net Signed-off-by: Martin K. Petersen martin.petersen@oracle.com
v2:
- Added warnings as requested by hch
- Moved the checks to a helper function
Before:
NAME ALIGNMENT MIN-IO OPT-IO PHY-SEC LOG-SEC ROTA SCHED RQ-SIZE RA WSAME sda 0 4096 33553920 4096 512 0 mq-deadline 256 128 32M
After:
NAME ALIGNMENT MIN-IO OPT-IO PHY-SEC LOG-SEC ROTA SCHED RQ-SIZE RA WSAME sda 0 4096 0 4096 512 0 mq-deadline 256 4096 32M
drivers/scsi/sd.c | 59 +++++++++++++++++++++++++++++++++++++++-------- 1 file changed, 50 insertions(+), 9 deletions(-)
diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c index 9aa409b38765..5dfe37b08d3b 100644 --- a/drivers/scsi/sd.c +++ b/drivers/scsi/sd.c @@ -3048,6 +3048,55 @@ static void sd_read_security(struct scsi_disk *sdkp, unsigned char *buffer) sdkp->security = 1; } +/*
- Determine the device's preferred I/O size for reads and writes
- unless the reported value is unreasonably small, large, not a
- multiple of the physical block size, or simply garbage.
- */
+static bool sd_validate_opt_xfer_size(struct scsi_disk *sdkp,
unsigned int dev_max)+{
- struct scsi_device *sdp = sdkp->device;
- unsigned int opt_xfer_bytes =
logical_to_bytes(sdp, sdkp->opt_xfer_blocks);- if (sdkp->opt_xfer_blocks > dev_max) {
sd_first_printk(KERN_WARNING, sdkp,"Optimal transfer size %u logical blocks " \"> dev_max (%u logical blocks)\n",sdkp->opt_xfer_blocks, dev_max);return false;- }
- if (sdkp->opt_xfer_blocks > SD_DEF_XFER_BLOCKS) {
sd_first_printk(KERN_WARNING, sdkp,"Optimal transfer size %u logical blocks " \"> sd driver limit (%u logical blocks)\n",sdkp->opt_xfer_blocks, SD_DEF_XFER_BLOCKS);return false;- }
- if (opt_xfer_bytes < PAGE_SIZE) {
sd_first_printk(KERN_WARNING, sdkp,"Optimal transfer size %u bytes < " \"PAGE_SIZE (%u bytes)\n",opt_xfer_bytes, (unsigned int)PAGE_SIZE);return false;- }
- if (opt_xfer_bytes & (sdkp->physical_block_size - 1)) {
sd_first_printk(KERN_WARNING, sdkp,"Optimal transfer size %u bytes not a " \"multiple of physical block size (%u bytes)\n",opt_xfer_bytes, sdkp->physical_block_size);return false;- }
- sd_first_printk(KERN_INFO, sdkp, "Optimal transfer size %u bytes\n",
opt_xfer_bytes);- return true;
+}
/**
- sd_revalidate_disk - called the first time a new disk is seen,
- performs disk spin up, read_capacity, etc.
@@ -3117,15 +3166,7 @@ static int sd_revalidate_disk(struct gendisk *disk) dev_max = min_not_zero(dev_max, sdkp->max_xfer_blocks); q->limits.max_dev_sectors = logical_to_sectors(sdp, dev_max);
- /*
* Determine the device's preferred I/O size for reads and writes* unless the reported value is unreasonably small, large, or* garbage.*/- if (sdkp->opt_xfer_blocks &&
sdkp->opt_xfer_blocks <= dev_max &&sdkp->opt_xfer_blocks <= SD_DEF_XFER_BLOCKS &&logical_to_bytes(sdp, sdkp->opt_xfer_blocks) >= PAGE_SIZE) {
- if (sd_validate_opt_xfer_size(sdkp, dev_max)) { q->limits.io_opt = logical_to_bytes(sdp, sdkp->opt_xfer_blocks); rw_max = logical_to_sectors(sdp, sdkp->opt_xfer_blocks); } else