Commit 1b7d0d28 authored by Stephen M. Cameron's avatar Stephen M. Cameron Committed by Jens Axboe
Browse files

cciss: detect bad alignment of scsi commands at build time 



cciss: detect bad alignment of scsi commands at build time
Incidentally fix some nearby c++ style comments.

Signed-off-by: default avatarStephen M. Cameron <scameron@beardog.cce.hp.com>
Signed-off-by: default avatarJens Axboe <jens.axboe@oracle.com>
parent 58daa9ce

drivers/block/cciss.c

+1 −1
Original line number Diff line number Diff line
@@ -4496,7 +4496,7 @@ static int __init cciss_init(void) 
	 * boundary. Given that we use pci_alloc_consistent() to allocate an

	 * array of them, the size must be a multiple of 8 bytes.

	 */

	BUILD_BUG_ON(sizeof(CommandList_struct) % 8);

	BUILD_BUG_ON(sizeof(CommandList_struct) % COMMANDLIST_ALIGNMENT);



	printk(KERN_INFO DRIVER_NAME "\n");

drivers/block/cciss_cmd.h

+6 −3
Original line number Diff line number Diff line
@@ -167,10 +167,13 @@ typedef struct _SGDescriptor_struct { 
#define CMD_MSG_TIMEOUT 0x05

#define CMD_MSG_STALE	0xff



/* This structure needs to be divisible by 8 for new

 * indexing method.  PAD_32 and PAD_64 can be adjusted

 * independently as needed for 32-bit and 64-bits systems.

/* This structure needs to be divisible by COMMANDLIST_ALIGNMENT

 * because low bits of the address are used to to indicate that

 * whether the tag contains an index or an address.  PAD_32 and

 * PAD_64 can be adjusted independently as needed for 32-bit

 * and 64-bits systems.

 */

#define COMMANDLIST_ALIGNMENT (8)

#define IS_64_BIT ((sizeof(long) - 4)/4)

#define IS_32_BIT (!IS_64_BIT)

#define PAD_32 (0)

drivers/block/cciss_scsi.c

+8 −4
Original line number Diff line number Diff line
@@ -93,11 +93,15 @@ static struct scsi_host_template cciss_driver_template = { 
};



#pragma pack(1)



#define SCSI_PAD_32 4

#define SCSI_PAD_64 4



struct cciss_scsi_cmd_stack_elem_t {

	CommandList_struct cmd;

	ErrorInfo_struct Err;

	__u32 busaddr;

	__u32 pad;

	u8 pad[IS_32_BIT * SCSI_PAD_32 + IS_64_BIT * SCSI_PAD_64];

};



#pragma pack()
@@ -202,9 +206,9 @@ scsi_cmd_stack_setup(int ctlr, struct cciss_scsi_adapter_data_t *sa) 
	stk = &sa->cmd_stack; 

	size = sizeof(struct cciss_scsi_cmd_stack_elem_t) * CMD_STACK_SIZE;



	// pci_alloc_consistent guarantees 32-bit DMA address will

	// be used



	/* Check alignment, see cciss_cmd.h near CommandList_struct def. */

	BUILD_BUG_ON((sizeof(*stk->pool) % COMMANDLIST_ALIGNMENT) != 0);

	/* pci_alloc_consistent guarantees 32-bit DMA address will be used */

	stk->pool = (struct cciss_scsi_cmd_stack_elem_t *)

		pci_alloc_consistent(hba[ctlr]->pdev, size, &stk->cmd_pool_handle);