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ata: libata-core: fix sloppy typing in ata_id_n_sectors() 

The code multiplying the # of cylinders/heads/sectors in ata_id_n_sectors()
to get a disk capacity implicitly uses the *int* type for that calculation
and casting the result to 'u64' before returning ensues a sign extension.
Explicitly casting the 'u16' typed multipliers to 'u32' results in avoiding
a sign extension instruction and so in a more compact code...

Found by Linux Verification Center (linuxtesting.org) with the SVACE static
analysis tool.

Signed-off-by: Sergey Shtylyov <s.shtylyov@omp.ru>
Signed-off-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
This commit is contained in:
Sergey Shtylyov 2022-05-13 23:50:14 +03:00 committed by Damien Le Moal
parent 6cd379f75f
commit 79ad6a5619
1 changed files with 6 additions and 4 deletions
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10
drivers/ata/libata-core.c
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@ -1107,11 +1107,13 @@ static u64 ata_id_n_sectors(const u16 *id)
return ata_id_u32(id, ATA_ID_LBA_CAPACITY);
} else {
if (ata_id_current_chs_valid(id))
return id[ATA_ID_CUR_CYLS] * id[ATA_ID_CUR_HEADS] *
id[ATA_ID_CUR_SECTORS];
return (u32)id[ATA_ID_CUR_CYLS] *
(u32)id[ATA_ID_CUR_HEADS] *
(u32)id[ATA_ID_CUR_SECTORS];
else
return id[ATA_ID_CYLS] * id[ATA_ID_HEADS] *
id[ATA_ID_SECTORS];
return (u32)id[ATA_ID_CYLS] *
(u32)id[ATA_ID_HEADS] *
(u32)id[ATA_ID_SECTORS];
}
}