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| author | Damien Le Moal <damien.lemoal@wdc.com> | 2020-05-07 04:35:26 +0200 |
|---|---|---|
| committer | Martin K. Petersen <martin.petersen@oracle.com> | 2020-05-08 02:45:02 +0200 |
| commit | 108e36f0d8bf91839613d8053a6d1354965801b0 (patch) | |
| tree | 6791e13e7771e7189956788ea3819c4650238ca3 /drivers/scsi/scsi_debug.c | |
| parent | scsi: scsi_debug: Implement ZBC host-aware emulation (diff) | |
| download | linux-108e36f0d8bf91839613d8053a6d1354965801b0.tar.xz linux-108e36f0d8bf91839613d8053a6d1354965801b0.zip | |
scsi: scsi_debug: Disallow zone sizes that are not powers of 2
Allowing a non-power-of-2 zone size forces the use of direct division
operations of 64-bit sector values to obtain a zone number or number of
zones. Doing so without using do_div() leads to compilation errors on
32-bit architectures.
Devices with a zone size that is not a power of 2 do not exist today so
allowing their emulation is of limited interest as the sd driver will not
support them anyway. To fix this compilation error, instead of using
do_div() for sector values divisions, simply disallow zone size values that
are not a power of 2.
[mkp: commit desc]
Link: https://lore.kernel.org/r/20200507023526.221574-1-damien.lemoal@wdc.com
Fixes: 98e0a689868c ("scsi: scsi_debug: Add zone_size_mb module parameter")
Fixes: f0d1cf9378bd ("scsi: scsi_debug: Add ZBC zone commands")
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Diffstat (limited to 'drivers/scsi/scsi_debug.c')
| -rw-r--r-- | drivers/scsi/scsi_debug.c | 17 |
1 files changed, 7 insertions, 10 deletions
diff --git a/drivers/scsi/scsi_debug.c b/drivers/scsi/scsi_debug.c index d3ea16f3c12e..105e563d87b4 100644 --- a/drivers/scsi/scsi_debug.c +++ b/drivers/scsi/scsi_debug.c @@ -2657,13 +2657,7 @@ static inline bool sdebug_dev_is_zoned(struct sdebug_dev_info *devip) static struct sdeb_zone_state *zbc_zone(struct sdebug_dev_info *devip, unsigned long long lba) { - unsigned int zno; - - if (devip->zsize_shift) - zno = lba >> devip->zsize_shift; - else - zno = lba / devip->zsize; - return &devip->zstate[zno]; + return &devip->zstate[lba >> devip->zsize_shift]; } static inline bool zbc_zone_is_conv(struct sdeb_zone_state *zsp) @@ -4306,7 +4300,7 @@ static int resp_report_zones(struct scsi_cmnd *scp, return check_condition_result; } - max_zones = devip->nr_zones - zs_lba / devip->zsize; + max_zones = devip->nr_zones - (zs_lba >> devip->zsize_shift); rep_max_zones = min((alloc_len - 64) >> ilog2(RZONES_DESC_HD), max_zones); @@ -4826,6 +4820,10 @@ static int sdebug_device_create_zones(struct sdebug_dev_info *devip) return -EINVAL; } } else { + if (!is_power_of_2(sdeb_zbc_zone_size_mb)) { + pr_err("Zone size is not a power of 2\n"); + return -EINVAL; + } devip->zsize = (sdeb_zbc_zone_size_mb * SZ_1M) >> ilog2(sdebug_sector_size); if (devip->zsize >= capacity) { @@ -4834,8 +4832,7 @@ static int sdebug_device_create_zones(struct sdebug_dev_info *devip) } } - if (is_power_of_2(devip->zsize)) - devip->zsize_shift = ilog2(devip->zsize); + devip->zsize_shift = ilog2(devip->zsize); devip->nr_zones = (capacity + devip->zsize - 1) >> devip->zsize_shift; if (sdeb_zbc_nr_conv >= devip->nr_zones) { |