Commit abd12b09 authored by Finn Thain's avatar Finn Thain Committed by Martin K. Petersen
Browse files

scsi: atari_scsi: Make device register accessors re-entrant 



This patch fixes an old bug: accesses to device registers from the
interrupt handler (after reselection, DMA completion etc.) could mess
up a device register access elsewhere, if the latter takes place outside
of an irq lock (during selection etc.).

Signed-off-by: default avatarFinn Thain <fthain@telegraphics.com.au>
Reviewed-by: default avatarHannes Reinecke <hare@suse.com>
Tested-by: default avatarMichael Schmitz <schmitzmic@gmail.com>
Signed-off-by: default avatarMartin K. Petersen <martin.petersen@oracle.com>
parent b223680d

drivers/scsi/atari_scsi.c

+15 −3
Original line number Diff line number Diff line
@@ -670,14 +670,26 @@ static void atari_scsi_tt_reg_write(unsigned char reg, unsigned char value) 


static unsigned char atari_scsi_falcon_reg_read(unsigned char reg)

{

	dma_wd.dma_mode_status= (u_short)(0x88 + reg);

	return (u_char)dma_wd.fdc_acces_seccount;

	unsigned long flags;

	unsigned char result;



	reg += 0x88;

	local_irq_save(flags);

	dma_wd.dma_mode_status = (u_short)reg;

	result = (u_char)dma_wd.fdc_acces_seccount;

	local_irq_restore(flags);

	return result;

}



static void atari_scsi_falcon_reg_write(unsigned char reg, unsigned char value)

{

	dma_wd.dma_mode_status = (u_short)(0x88 + reg);

	unsigned long flags;



	reg += 0x88;

	local_irq_save(flags);

	dma_wd.dma_mode_status = (u_short)reg;

	dma_wd.fdc_acces_seccount = (u_short)value;

	local_irq_restore(flags);

}