diff options
| author | John Garry | 2022-08-17 23:20:08 +0800 |
|---|---|---|
| committer | Damien Le Moal | 2022-08-21 01:29:50 +0900 |
| commit | a357f7b4583ebf81d19c95aef57497ae81c5f63c (patch) | |
| tree | e7a6e301988a8d1889d6ceec03b8e460d0fb815e | |
| parent | d3122bf9aa4c974f5e2c0112f799757b3a2779da (diff) | |
ata: libata: Set __ATA_BASE_SHT max_sectors
Commit 0568e6122574 ("ata: libata-scsi: cap ata_device->max_sectors
according to shost->max_sectors") inadvertently capped the max_sectors
value for some SATA disks to a value which is lower than we would want.
For a device which supports LBA48, we would previously have request queue
max_sectors_kb and max_hw_sectors_kb values of 1280 and 32767 respectively.
For AHCI controllers, the value chosen for shost max sectors comes from
the minimum of the SCSI host default max sectors in
SCSI_DEFAULT_MAX_SECTORS (1024) and the shost DMA device mapping limit.
This means that we would now set the max_sectors_kb and max_hw_sectors_kb
values for a disk which supports LBA48 at 512, ignoring DMA mapping limit.
As report by Oliver at [0], this caused a performance regression.
Fix by picking a large enough max sectors value for ATA host controllers
such that we don't needlessly reduce max_sectors_kb for LBA48 disks.
[0] https://lore.kernel.org/linux-ide/YvsGbidf3na5FpGb@xsang-OptiPlex-9020/T/#m22d9fc5ad15af66066dd9fecf3d50f1b1ef11da3
Fixes: 0568e6122574 ("ata: libata-scsi: cap ata_device->max_sectors according to shost->max_sectors")
Reported-by: Oliver Sang <oliver.sang@intel.com>
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
| -rw-r--r-- | include/linux/libata.h | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/include/linux/libata.h b/include/linux/libata.h index 0269ff114f5a..698032e5ef2d 100644 --- a/include/linux/libata.h +++ b/include/linux/libata.h @@ -1382,7 +1382,8 @@ extern const struct attribute_group *ata_common_sdev_groups[]; .proc_name = drv_name, \ .slave_destroy = ata_scsi_slave_destroy, \ .bios_param = ata_std_bios_param, \ - .unlock_native_capacity = ata_scsi_unlock_native_capacity + .unlock_native_capacity = ata_scsi_unlock_native_capacity,\ + .max_sectors = ATA_MAX_SECTORS_LBA48 #define ATA_SUBBASE_SHT(drv_name) \ __ATA_BASE_SHT(drv_name), \ |