cciss: Add enhanced scatter-gather support.
cciss: Add enhanced scatter-gather support. For controllers which
supported, more than 512 scatter-gather elements per command may
be used, and the max transfer size can be increased to 8192 blocks.
Signed-off-by: Don Brace <brace@beardog.cce.hp.com>
Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
diff --git a/drivers/block/cciss.c b/drivers/block/cciss.c
index bf2d1c8..1bd313d 100644
--- a/drivers/block/cciss.c
+++ b/drivers/block/cciss.c
@@ -1655,9 +1655,11 @@
{
CommandList_struct *cmd = rq->completion_data;
ctlr_info_t *h = hba[cmd->ctlr];
+ SGDescriptor_struct *curr_sg = cmd->SG;
unsigned long flags;
u64bit temp64;
int i, ddir;
+ int sg_index = 0;
if (cmd->Request.Type.Direction == XFER_READ)
ddir = PCI_DMA_FROMDEVICE;
@@ -1667,9 +1669,22 @@
/* command did not need to be retried */
/* unmap the DMA mapping for all the scatter gather elements */
for (i = 0; i < cmd->Header.SGList; i++) {
- temp64.val32.lower = cmd->SG[i].Addr.lower;
- temp64.val32.upper = cmd->SG[i].Addr.upper;
- pci_unmap_page(h->pdev, temp64.val, cmd->SG[i].Len, ddir);
+ if (curr_sg[sg_index].Ext == CCISS_SG_CHAIN) {
+ temp64.val32.lower = cmd->SG[i].Addr.lower;
+ temp64.val32.upper = cmd->SG[i].Addr.upper;
+ pci_dma_sync_single_for_cpu(h->pdev, temp64.val,
+ cmd->SG[i].Len, ddir);
+ pci_unmap_single(h->pdev, temp64.val,
+ cmd->SG[i].Len, ddir);
+ /* Point to the next block */
+ curr_sg = h->cmd_sg_list[cmd->cmdindex]->sgchain;
+ sg_index = 0;
+ }
+ temp64.val32.lower = curr_sg[sg_index].Addr.lower;
+ temp64.val32.upper = curr_sg[sg_index].Addr.upper;
+ pci_unmap_page(h->pdev, temp64.val, curr_sg[sg_index].Len,
+ ddir);
+ ++sg_index;
}
#ifdef CCISS_DEBUG
@@ -1781,10 +1796,10 @@
blk_queue_bounce_limit(disk->queue, h->pdev->dma_mask);
/* This is a hardware imposed limit. */
- blk_queue_max_hw_segments(disk->queue, MAXSGENTRIES);
+ blk_queue_max_hw_segments(disk->queue, h->maxsgentries);
/* This is a limit in the driver and could be eliminated. */
- blk_queue_max_phys_segments(disk->queue, MAXSGENTRIES);
+ blk_queue_max_phys_segments(disk->queue, h->maxsgentries);
blk_queue_max_sectors(disk->queue, h->cciss_max_sectors);
@@ -3063,9 +3078,13 @@
int seg;
struct request *creq;
u64bit temp64;
- struct scatterlist tmp_sg[MAXSGENTRIES];
+ struct scatterlist *tmp_sg;
+ SGDescriptor_struct *curr_sg;
drive_info_struct *drv;
int i, dir;
+ int nseg = 0;
+ int sg_index = 0;
+ int chained = 0;
/* We call start_io here in case there is a command waiting on the
* queue that has not been sent.
@@ -3078,13 +3097,14 @@
if (!creq)
goto startio;
- BUG_ON(creq->nr_phys_segments > MAXSGENTRIES);
+ BUG_ON(creq->nr_phys_segments > h->maxsgentries);
if ((c = cmd_alloc(h, 1)) == NULL)
goto full;
blk_start_request(creq);
+ tmp_sg = h->scatter_list[c->cmdindex];
spin_unlock_irq(q->queue_lock);
c->cmd_type = CMD_RWREQ;
@@ -3113,7 +3133,7 @@
(int)blk_rq_pos(creq), (int)blk_rq_sectors(creq));
#endif /* CCISS_DEBUG */
- sg_init_table(tmp_sg, MAXSGENTRIES);
+ sg_init_table(tmp_sg, h->maxsgentries);
seg = blk_rq_map_sg(q, creq, tmp_sg);
/* get the DMA records for the setup */
@@ -3122,25 +3142,70 @@
else
dir = PCI_DMA_TODEVICE;
+ curr_sg = c->SG;
+ sg_index = 0;
+ chained = 0;
+
for (i = 0; i < seg; i++) {
- c->SG[i].Len = tmp_sg[i].length;
+ if (((sg_index+1) == (h->max_cmd_sgentries)) &&
+ !chained && ((seg - i) > 1)) {
+ nseg = seg - i;
+ curr_sg[sg_index].Len = (nseg) *
+ sizeof(SGDescriptor_struct);
+ curr_sg[sg_index].Ext = CCISS_SG_CHAIN;
+
+ /* Point to next chain block. */
+ curr_sg = h->cmd_sg_list[c->cmdindex]->sgchain;
+ sg_index = 0;
+ chained = 1;
+ }
+ curr_sg[sg_index].Len = tmp_sg[i].length;
temp64.val = (__u64) pci_map_page(h->pdev, sg_page(&tmp_sg[i]),
- tmp_sg[i].offset,
- tmp_sg[i].length, dir);
- c->SG[i].Addr.lower = temp64.val32.lower;
- c->SG[i].Addr.upper = temp64.val32.upper;
- c->SG[i].Ext = 0; // we are not chaining
+ tmp_sg[i].offset,
+ tmp_sg[i].length, dir);
+ curr_sg[sg_index].Addr.lower = temp64.val32.lower;
+ curr_sg[sg_index].Addr.upper = temp64.val32.upper;
+ curr_sg[sg_index].Ext = 0; /* we are not chaining */
+
+ ++sg_index;
}
+
+ if (chained) {
+ int len;
+ curr_sg = c->SG;
+ sg_index = h->max_cmd_sgentries - 1;
+ len = curr_sg[sg_index].Len;
+ /* Setup pointer to next chain block.
+ * Fill out last element in current chain
+ * block with address of next chain block.
+ */
+ temp64.val = pci_map_single(h->pdev,
+ h->cmd_sg_list[c->cmdindex]->sgchain,
+ len, dir);
+
+ h->cmd_sg_list[c->cmdindex]->sg_chain_dma = temp64.val;
+ curr_sg[sg_index].Addr.lower = temp64.val32.lower;
+ curr_sg[sg_index].Addr.upper = temp64.val32.upper;
+
+ pci_dma_sync_single_for_device(h->pdev,
+ h->cmd_sg_list[c->cmdindex]->sg_chain_dma,
+ len, dir);
+ }
+
/* track how many SG entries we are using */
if (seg > h->maxSG)
h->maxSG = seg;
#ifdef CCISS_DEBUG
- printk(KERN_DEBUG "cciss: Submitting %u sectors in %d segments\n",
- blk_rq_sectors(creq), seg);
+ printk(KERN_DEBUG "cciss: Submitting %ld sectors in %d segments "
+ "chained[%d]\n",
+ blk_rq_sectors(creq), seg, chained);
#endif /* CCISS_DEBUG */
- c->Header.SGList = c->Header.SGTotal = seg;
+ c->Header.SGList = c->Header.SGTotal = seg + chained;
+ if (seg > h->max_cmd_sgentries)
+ c->Header.SGList = h->max_cmd_sgentries;
+
if (likely(blk_fs_request(creq))) {
if(h->cciss_read == CCISS_READ_10) {
c->Request.CDB[1] = 0;
@@ -3713,6 +3778,23 @@
* leave a little room for ioctl calls.
*/
c->max_commands = readl(&(c->cfgtable->CmdsOutMax));
+ c->maxsgentries = readl(&(c->cfgtable->MaxSGElements));
+
+ /*
+ * Limit native command to 32 s/g elements to save dma'able memory.
+ * Howvever spec says if 0, use 31
+ */
+
+ c->max_cmd_sgentries = 31;
+ if (c->maxsgentries > 512) {
+ c->max_cmd_sgentries = 32;
+ c->chainsize = c->maxsgentries - c->max_cmd_sgentries + 1;
+ c->maxsgentries -= 1; /* account for chain pointer */
+ } else {
+ c->maxsgentries = 31; /* Default to traditional value */
+ c->chainsize = 0; /* traditional */
+ }
+
c->product_name = products[prod_index].product_name;
c->access = *(products[prod_index].access);
c->nr_cmds = c->max_commands - 4;
@@ -4039,6 +4121,7 @@
{
int i;
int j = 0;
+ int k = 0;
int rc;
int dac, return_code;
InquiryData_struct *inq_buff;
@@ -4142,6 +4225,53 @@
printk(KERN_ERR "cciss: out of memory");
goto clean4;
}
+
+ /* Need space for temp scatter list */
+ hba[i]->scatter_list = kmalloc(hba[i]->max_commands *
+ sizeof(struct scatterlist *),
+ GFP_KERNEL);
+ for (k = 0; k < hba[i]->nr_cmds; k++) {
+ hba[i]->scatter_list[k] = kmalloc(sizeof(struct scatterlist) *
+ hba[i]->maxsgentries,
+ GFP_KERNEL);
+ if (hba[i]->scatter_list[k] == NULL) {
+ printk(KERN_ERR "cciss%d: could not allocate "
+ "s/g lists\n", i);
+ goto clean4;
+ }
+ }
+ hba[i]->cmd_sg_list = kmalloc(sizeof(struct Cmd_sg_list *) *
+ hba[i]->nr_cmds,
+ GFP_KERNEL);
+ if (!hba[i]->cmd_sg_list) {
+ printk(KERN_ERR "cciss%d: Cannot get memory for "
+ "s/g chaining.\n", i);
+ goto clean4;
+ }
+ /* Build up chain blocks for each command */
+ if (hba[i]->chainsize > 0) {
+ for (j = 0; j < hba[i]->nr_cmds; j++) {
+ hba[i]->cmd_sg_list[j] =
+ kmalloc(sizeof(struct Cmd_sg_list),
+ GFP_KERNEL);
+ if (!hba[i]->cmd_sg_list[j]) {
+ printk(KERN_ERR "cciss%d: Cannot get memory "
+ "for chain block.\n", i);
+ goto clean4;
+ }
+ /* Need a block of chainsized s/g elements. */
+ hba[i]->cmd_sg_list[j]->sgchain =
+ kmalloc((hba[i]->chainsize *
+ sizeof(SGDescriptor_struct)),
+ GFP_KERNEL);
+ if (!hba[i]->cmd_sg_list[j]->sgchain) {
+ printk(KERN_ERR "cciss%d: Cannot get memory "
+ "for s/g chains\n", i);
+ goto clean4;
+ }
+ }
+ }
+
spin_lock_init(&hba[i]->lock);
/* Initialize the pdev driver private data.
@@ -4187,7 +4317,7 @@
cciss_procinit(i);
- hba[i]->cciss_max_sectors = 2048;
+ hba[i]->cciss_max_sectors = 8192;
rebuild_lun_table(hba[i], 1, 0);
hba[i]->busy_initializing = 0;
@@ -4195,6 +4325,15 @@
clean4:
kfree(hba[i]->cmd_pool_bits);
+ /* Free up sg elements */
+ for (k = 0; k < hba[i]->nr_cmds; k++)
+ kfree(hba[i]->scatter_list[k]);
+ kfree(hba[i]->scatter_list);
+ for (j = 0; j < hba[i]->nr_cmds; j++) {
+ if (hba[i]->cmd_sg_list[j])
+ kfree(hba[i]->cmd_sg_list[j]->sgchain);
+ kfree(hba[i]->cmd_sg_list[j]);
+ }
if (hba[i]->cmd_pool)
pci_free_consistent(hba[i]->pdev,
hba[i]->nr_cmds * sizeof(CommandList_struct),
@@ -4308,6 +4447,14 @@
pci_free_consistent(hba[i]->pdev, hba[i]->nr_cmds * sizeof(ErrorInfo_struct),
hba[i]->errinfo_pool, hba[i]->errinfo_pool_dhandle);
kfree(hba[i]->cmd_pool_bits);
+ /* Free up sg elements */
+ for (j = 0; j < hba[i]->nr_cmds; j++)
+ kfree(hba[i]->scatter_list[j]);
+ kfree(hba[i]->scatter_list);
+ for (j = 0; j < hba[i]->nr_cmds; j++) {
+ kfree(hba[i]->cmd_sg_list[j]->sgchain);
+ kfree(hba[i]->cmd_sg_list[j]);
+ }
/*
* Deliberately omit pci_disable_device(): it does something nasty to
* Smart Array controllers that pci_enable_device does not undo
diff --git a/drivers/block/cciss.h b/drivers/block/cciss.h
index 31524cf..e5c63e5 100644
--- a/drivers/block/cciss.h
+++ b/drivers/block/cciss.h
@@ -55,7 +55,13 @@
char device_initialized; /* indicates whether dev is initialized */
} drive_info_struct;
-struct ctlr_info
+struct Cmd_sg_list {
+ SGDescriptor_struct *sgchain;
+ dma64_addr_t sg_chain_dma;
+ int chain_block_size;
+};
+
+struct ctlr_info
{
int ctlr;
char devname[8];
@@ -75,6 +81,16 @@
int num_luns;
int highest_lun;
int usage_count; /* number of opens all all minor devices */
+ /* Need space for temp sg list
+ * number of scatter/gathers supported
+ * number of scatter/gathers in chained block
+ */
+ struct scatterlist **scatter_list;
+ int maxsgentries;
+ int chainsize;
+ int max_cmd_sgentries;
+ struct Cmd_sg_list **cmd_sg_list;
+
# define DOORBELL_INT 0
# define PERF_MODE_INT 1
# define SIMPLE_MODE_INT 2
diff --git a/drivers/block/cciss_cmd.h b/drivers/block/cciss_cmd.h
index dbaed1e..b50a9b2 100644
--- a/drivers/block/cciss_cmd.h
+++ b/drivers/block/cciss_cmd.h
@@ -7,7 +7,8 @@
//general boundary defintions
#define SENSEINFOBYTES 32//note that this value may vary between host implementations
-#define MAXSGENTRIES 31
+#define MAXSGENTRIES 32
+#define CCISS_SG_CHAIN 0x80000000
#define MAXREPLYQS 256
//Command Status value
@@ -319,6 +320,10 @@
BYTE ServerName[16];
DWORD HeartBeat;
DWORD SCSI_Prefetch;
+ DWORD MaxSGElements;
+ DWORD MaxLogicalUnits;
+ DWORD MaxPhysicalDrives;
+ DWORD MaxPhysicalDrivesPerLogicalUnit;
} CfgTable_struct;
#pragma pack()
#endif // CCISS_CMD_H