Commit aa7b5cd7 authored by Mike Christie's avatar Mike Christie Committed by James Bottomley
Browse files

[SCSI] add kmemcache for scsi_io_context 



Add kmemcache of scsi io contexts.

In the future when we finalize on where these functions will live
we can add a mempool for it and do a bioset for out REQ_BLOCK_PC
bios. This is needed becuase the dm-multipath handlers will
want to use the scsi_exectute* functions for failover and we cannot
have them and the bio device allocating from the same mempool.

Signed-off-by: default avatarMike Christie <michaelc@cs.wisc.edu>
Signed-off-by: default avatarJames Bottomley <James.Bottomley@SteelEye.com>
parent 0d95716d

drivers/scsi/scsi_lib.c

+15 −2
Original line number Diff line number Diff line
@@ -306,6 +306,8 @@ struct scsi_io_context { 
	char sense[SCSI_SENSE_BUFFERSIZE];

};



static kmem_cache_t *scsi_io_context_cache;



static void scsi_end_async(struct request *req)

{

	struct scsi_io_context *sioc = req->end_io_data;
@@ -313,7 +315,7 @@ static void scsi_end_async(struct request *req) 
	if (sioc->done)

		sioc->done(sioc->data, sioc->sense, req->errors, req->data_len);



	kfree(sioc);

	kmem_cache_free(scsi_io_context_cache, sioc);

	__blk_put_request(req->q, req);

}
@@ -452,9 +454,10 @@ int scsi_execute_async(struct scsi_device *sdev, const unsigned char *cmd, 
	int err = 0;

	int write = (data_direction == DMA_TO_DEVICE);



	sioc = kzalloc(sizeof(*sioc), gfp);

	sioc = kmem_cache_alloc(scsi_io_context_cache, gfp);

	if (!sioc)

		return DRIVER_ERROR << 24;

	memset(sioc, 0, sizeof(*sioc));



	req = blk_get_request(sdev->request_queue, write, gfp);

	if (!req)
@@ -1765,6 +1768,14 @@ int __init scsi_init_queue(void) 
{

	int i;



	scsi_io_context_cache = kmem_cache_create("scsi_io_context",

					sizeof(struct scsi_io_context),

					0, 0, NULL, NULL);

	if (!scsi_io_context_cache) {

		printk(KERN_ERR "SCSI: can't init scsi io context cache\n");

		return -ENOMEM;

	}



	for (i = 0; i < SG_MEMPOOL_NR; i++) {

		struct scsi_host_sg_pool *sgp = scsi_sg_pools + i;

		int size = sgp->size * sizeof(struct scatterlist);
@@ -1792,6 +1803,8 @@ void scsi_exit_queue(void) 
{

	int i;



	kmem_cache_destroy(scsi_io_context_cache);



	for (i = 0; i < SG_MEMPOOL_NR; i++) {

		struct scsi_host_sg_pool *sgp = scsi_sg_pools + i;

		mempool_destroy(sgp->pool);

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