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Diffstat (limited to 'drivers/scsi/vmw_pvscsi.c')
-rw-r--r--drivers/scsi/vmw_pvscsi.c1621
1 files changed, 1621 insertions, 0 deletions
diff --git a/drivers/scsi/vmw_pvscsi.c b/drivers/scsi/vmw_pvscsi.c
new file mode 100644
index 0000000000..f88ecdb93a
--- /dev/null
+++ b/drivers/scsi/vmw_pvscsi.c
@@ -0,0 +1,1621 @@
+/*
+ * Linux driver for VMware's para-virtualized SCSI HBA.
+ *
+ * Copyright (C) 2008-2014, VMware, Inc. All Rights Reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; version 2 of the License and no later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
+ * NON INFRINGEMENT. See the GNU General Public License for more
+ * details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/interrupt.h>
+#include <linux/slab.h>
+#include <linux/workqueue.h>
+#include <linux/pci.h>
+
+#include <scsi/scsi.h>
+#include <scsi/scsi_host.h>
+#include <scsi/scsi_cmnd.h>
+#include <scsi/scsi_device.h>
+#include <scsi/scsi_tcq.h>
+
+#include "vmw_pvscsi.h"
+
+#define PVSCSI_LINUX_DRIVER_DESC "VMware PVSCSI driver"
+
+MODULE_DESCRIPTION(PVSCSI_LINUX_DRIVER_DESC);
+MODULE_AUTHOR("VMware, Inc.");
+MODULE_LICENSE("GPL");
+MODULE_VERSION(PVSCSI_DRIVER_VERSION_STRING);
+
+#define PVSCSI_DEFAULT_NUM_PAGES_PER_RING 8
+#define PVSCSI_DEFAULT_NUM_PAGES_MSG_RING 1
+#define PVSCSI_DEFAULT_QUEUE_DEPTH 254
+#define SGL_SIZE PAGE_SIZE
+
+struct pvscsi_sg_list {
+ struct PVSCSISGElement sge[PVSCSI_MAX_NUM_SG_ENTRIES_PER_SEGMENT];
+};
+
+struct pvscsi_ctx {
+ /*
+ * The index of the context in cmd_map serves as the context ID for a
+ * 1-to-1 mapping completions back to requests.
+ */
+ struct scsi_cmnd *cmd;
+ struct pvscsi_sg_list *sgl;
+ struct list_head list;
+ dma_addr_t dataPA;
+ dma_addr_t sensePA;
+ dma_addr_t sglPA;
+ struct completion *abort_cmp;
+};
+
+struct pvscsi_adapter {
+ char *mmioBase;
+ u8 rev;
+ bool use_msg;
+ bool use_req_threshold;
+
+ spinlock_t hw_lock;
+
+ struct workqueue_struct *workqueue;
+ struct work_struct work;
+
+ struct PVSCSIRingReqDesc *req_ring;
+ unsigned req_pages;
+ unsigned req_depth;
+ dma_addr_t reqRingPA;
+
+ struct PVSCSIRingCmpDesc *cmp_ring;
+ unsigned cmp_pages;
+ dma_addr_t cmpRingPA;
+
+ struct PVSCSIRingMsgDesc *msg_ring;
+ unsigned msg_pages;
+ dma_addr_t msgRingPA;
+
+ struct PVSCSIRingsState *rings_state;
+ dma_addr_t ringStatePA;
+
+ struct pci_dev *dev;
+ struct Scsi_Host *host;
+
+ struct list_head cmd_pool;
+ struct pvscsi_ctx *cmd_map;
+};
+
+
+/* Command line parameters */
+static int pvscsi_ring_pages;
+static int pvscsi_msg_ring_pages = PVSCSI_DEFAULT_NUM_PAGES_MSG_RING;
+static int pvscsi_cmd_per_lun = PVSCSI_DEFAULT_QUEUE_DEPTH;
+static bool pvscsi_disable_msi;
+static bool pvscsi_disable_msix;
+static bool pvscsi_use_msg = true;
+static bool pvscsi_use_req_threshold = true;
+
+#define PVSCSI_RW (S_IRUSR | S_IWUSR)
+
+module_param_named(ring_pages, pvscsi_ring_pages, int, PVSCSI_RW);
+MODULE_PARM_DESC(ring_pages, "Number of pages per req/cmp ring - (default="
+ __stringify(PVSCSI_DEFAULT_NUM_PAGES_PER_RING)
+ "[up to 16 targets],"
+ __stringify(PVSCSI_SETUP_RINGS_MAX_NUM_PAGES)
+ "[for 16+ targets])");
+
+module_param_named(msg_ring_pages, pvscsi_msg_ring_pages, int, PVSCSI_RW);
+MODULE_PARM_DESC(msg_ring_pages, "Number of pages for the msg ring - (default="
+ __stringify(PVSCSI_DEFAULT_NUM_PAGES_MSG_RING) ")");
+
+module_param_named(cmd_per_lun, pvscsi_cmd_per_lun, int, PVSCSI_RW);
+MODULE_PARM_DESC(cmd_per_lun, "Maximum commands per lun - (default="
+ __stringify(PVSCSI_DEFAULT_QUEUE_DEPTH) ")");
+
+module_param_named(disable_msi, pvscsi_disable_msi, bool, PVSCSI_RW);
+MODULE_PARM_DESC(disable_msi, "Disable MSI use in driver - (default=0)");
+
+module_param_named(disable_msix, pvscsi_disable_msix, bool, PVSCSI_RW);
+MODULE_PARM_DESC(disable_msix, "Disable MSI-X use in driver - (default=0)");
+
+module_param_named(use_msg, pvscsi_use_msg, bool, PVSCSI_RW);
+MODULE_PARM_DESC(use_msg, "Use msg ring when available - (default=1)");
+
+module_param_named(use_req_threshold, pvscsi_use_req_threshold,
+ bool, PVSCSI_RW);
+MODULE_PARM_DESC(use_req_threshold, "Use driver-based request coalescing if configured - (default=1)");
+
+static const struct pci_device_id pvscsi_pci_tbl[] = {
+ { PCI_VDEVICE(VMWARE, PCI_DEVICE_ID_VMWARE_PVSCSI) },
+ { 0 }
+};
+
+MODULE_DEVICE_TABLE(pci, pvscsi_pci_tbl);
+
+static struct device *
+pvscsi_dev(const struct pvscsi_adapter *adapter)
+{
+ return &(adapter->dev->dev);
+}
+
+static struct pvscsi_ctx *
+pvscsi_find_context(const struct pvscsi_adapter *adapter, struct scsi_cmnd *cmd)
+{
+ struct pvscsi_ctx *ctx, *end;
+
+ end = &adapter->cmd_map[adapter->req_depth];
+ for (ctx = adapter->cmd_map; ctx < end; ctx++)
+ if (ctx->cmd == cmd)
+ return ctx;
+
+ return NULL;
+}
+
+static struct pvscsi_ctx *
+pvscsi_acquire_context(struct pvscsi_adapter *adapter, struct scsi_cmnd *cmd)
+{
+ struct pvscsi_ctx *ctx;
+
+ if (list_empty(&adapter->cmd_pool))
+ return NULL;
+
+ ctx = list_first_entry(&adapter->cmd_pool, struct pvscsi_ctx, list);
+ ctx->cmd = cmd;
+ list_del(&ctx->list);
+
+ return ctx;
+}
+
+static void pvscsi_release_context(struct pvscsi_adapter *adapter,
+ struct pvscsi_ctx *ctx)
+{
+ ctx->cmd = NULL;
+ ctx->abort_cmp = NULL;
+ list_add(&ctx->list, &adapter->cmd_pool);
+}
+
+/*
+ * Map a pvscsi_ctx struct to a context ID field value; we map to a simple
+ * non-zero integer. ctx always points to an entry in cmd_map array, hence
+ * the return value is always >=1.
+ */
+static u64 pvscsi_map_context(const struct pvscsi_adapter *adapter,
+ const struct pvscsi_ctx *ctx)
+{
+ return ctx - adapter->cmd_map + 1;
+}
+
+static struct pvscsi_ctx *
+pvscsi_get_context(const struct pvscsi_adapter *adapter, u64 context)
+{
+ return &adapter->cmd_map[context - 1];
+}
+
+static void pvscsi_reg_write(const struct pvscsi_adapter *adapter,
+ u32 offset, u32 val)
+{
+ writel(val, adapter->mmioBase + offset);
+}
+
+static u32 pvscsi_reg_read(const struct pvscsi_adapter *adapter, u32 offset)
+{
+ return readl(adapter->mmioBase + offset);
+}
+
+static u32 pvscsi_read_intr_status(const struct pvscsi_adapter *adapter)
+{
+ return pvscsi_reg_read(adapter, PVSCSI_REG_OFFSET_INTR_STATUS);
+}
+
+static void pvscsi_write_intr_status(const struct pvscsi_adapter *adapter,
+ u32 val)
+{
+ pvscsi_reg_write(adapter, PVSCSI_REG_OFFSET_INTR_STATUS, val);
+}
+
+static void pvscsi_unmask_intr(const struct pvscsi_adapter *adapter)
+{
+ u32 intr_bits;
+
+ intr_bits = PVSCSI_INTR_CMPL_MASK;
+ if (adapter->use_msg)
+ intr_bits |= PVSCSI_INTR_MSG_MASK;
+
+ pvscsi_reg_write(adapter, PVSCSI_REG_OFFSET_INTR_MASK, intr_bits);
+}
+
+static void pvscsi_mask_intr(const struct pvscsi_adapter *adapter)
+{
+ pvscsi_reg_write(adapter, PVSCSI_REG_OFFSET_INTR_MASK, 0);
+}
+
+static void pvscsi_write_cmd_desc(const struct pvscsi_adapter *adapter,
+ u32 cmd, const void *desc, size_t len)
+{
+ const u32 *ptr = desc;
+ size_t i;
+
+ len /= sizeof(*ptr);
+ pvscsi_reg_write(adapter, PVSCSI_REG_OFFSET_COMMAND, cmd);
+ for (i = 0; i < len; i++)
+ pvscsi_reg_write(adapter,
+ PVSCSI_REG_OFFSET_COMMAND_DATA, ptr[i]);
+}
+
+static void pvscsi_abort_cmd(const struct pvscsi_adapter *adapter,
+ const struct pvscsi_ctx *ctx)
+{
+ struct PVSCSICmdDescAbortCmd cmd = { 0 };
+
+ cmd.target = ctx->cmd->device->id;
+ cmd.context = pvscsi_map_context(adapter, ctx);
+
+ pvscsi_write_cmd_desc(adapter, PVSCSI_CMD_ABORT_CMD, &cmd, sizeof(cmd));
+}
+
+static void pvscsi_kick_rw_io(const struct pvscsi_adapter *adapter)
+{
+ pvscsi_reg_write(adapter, PVSCSI_REG_OFFSET_KICK_RW_IO, 0);
+}
+
+static void pvscsi_process_request_ring(const struct pvscsi_adapter *adapter)
+{
+ pvscsi_reg_write(adapter, PVSCSI_REG_OFFSET_KICK_NON_RW_IO, 0);
+}
+
+static int scsi_is_rw(unsigned char op)
+{
+ return op == READ_6 || op == WRITE_6 ||
+ op == READ_10 || op == WRITE_10 ||
+ op == READ_12 || op == WRITE_12 ||
+ op == READ_16 || op == WRITE_16;
+}
+
+static void pvscsi_kick_io(const struct pvscsi_adapter *adapter,
+ unsigned char op)
+{
+ if (scsi_is_rw(op)) {
+ struct PVSCSIRingsState *s = adapter->rings_state;
+
+ if (!adapter->use_req_threshold ||
+ s->reqProdIdx - s->reqConsIdx >= s->reqCallThreshold)
+ pvscsi_kick_rw_io(adapter);
+ } else {
+ pvscsi_process_request_ring(adapter);
+ }
+}
+
+static void ll_adapter_reset(const struct pvscsi_adapter *adapter)
+{
+ dev_dbg(pvscsi_dev(adapter), "Adapter Reset on %p\n", adapter);
+
+ pvscsi_write_cmd_desc(adapter, PVSCSI_CMD_ADAPTER_RESET, NULL, 0);
+}
+
+static void ll_bus_reset(const struct pvscsi_adapter *adapter)
+{
+ dev_dbg(pvscsi_dev(adapter), "Resetting bus on %p\n", adapter);
+
+ pvscsi_write_cmd_desc(adapter, PVSCSI_CMD_RESET_BUS, NULL, 0);
+}
+
+static void ll_device_reset(const struct pvscsi_adapter *adapter, u32 target)
+{
+ struct PVSCSICmdDescResetDevice cmd = { 0 };
+
+ dev_dbg(pvscsi_dev(adapter), "Resetting device: target=%u\n", target);
+
+ cmd.target = target;
+
+ pvscsi_write_cmd_desc(adapter, PVSCSI_CMD_RESET_DEVICE,
+ &cmd, sizeof(cmd));
+}
+
+static void pvscsi_create_sg(struct pvscsi_ctx *ctx,
+ struct scatterlist *sg, unsigned count)
+{
+ unsigned i;
+ struct PVSCSISGElement *sge;
+
+ BUG_ON(count > PVSCSI_MAX_NUM_SG_ENTRIES_PER_SEGMENT);
+
+ sge = &ctx->sgl->sge[0];
+ for (i = 0; i < count; i++, sg = sg_next(sg)) {
+ sge[i].addr = sg_dma_address(sg);
+ sge[i].length = sg_dma_len(sg);
+ sge[i].flags = 0;
+ }
+}
+
+/*
+ * Map all data buffers for a command into PCI space and
+ * setup the scatter/gather list if needed.
+ */
+static int pvscsi_map_buffers(struct pvscsi_adapter *adapter,
+ struct pvscsi_ctx *ctx, struct scsi_cmnd *cmd,
+ struct PVSCSIRingReqDesc *e)
+{
+ unsigned count;
+ unsigned bufflen = scsi_bufflen(cmd);
+ struct scatterlist *sg;
+
+ e->dataLen = bufflen;
+ e->dataAddr = 0;
+ if (bufflen == 0)
+ return 0;
+
+ sg = scsi_sglist(cmd);
+ count = scsi_sg_count(cmd);
+ if (count != 0) {
+ int segs = scsi_dma_map(cmd);
+
+ if (segs == -ENOMEM) {
+ scmd_printk(KERN_DEBUG, cmd,
+ "vmw_pvscsi: Failed to map cmd sglist for DMA.\n");
+ return -ENOMEM;
+ } else if (segs > 1) {
+ pvscsi_create_sg(ctx, sg, segs);
+
+ e->flags |= PVSCSI_FLAG_CMD_WITH_SG_LIST;
+ ctx->sglPA = dma_map_single(&adapter->dev->dev,
+ ctx->sgl, SGL_SIZE, DMA_TO_DEVICE);
+ if (dma_mapping_error(&adapter->dev->dev, ctx->sglPA)) {
+ scmd_printk(KERN_ERR, cmd,
+ "vmw_pvscsi: Failed to map ctx sglist for DMA.\n");
+ scsi_dma_unmap(cmd);
+ ctx->sglPA = 0;
+ return -ENOMEM;
+ }
+ e->dataAddr = ctx->sglPA;
+ } else
+ e->dataAddr = sg_dma_address(sg);
+ } else {
+ /*
+ * In case there is no S/G list, scsi_sglist points
+ * directly to the buffer.
+ */
+ ctx->dataPA = dma_map_single(&adapter->dev->dev, sg, bufflen,
+ cmd->sc_data_direction);
+ if (dma_mapping_error(&adapter->dev->dev, ctx->dataPA)) {
+ scmd_printk(KERN_DEBUG, cmd,
+ "vmw_pvscsi: Failed to map direct data buffer for DMA.\n");
+ return -ENOMEM;
+ }
+ e->dataAddr = ctx->dataPA;
+ }
+
+ return 0;
+}
+
+/*
+ * The device incorrectly doesn't clear the first byte of the sense
+ * buffer in some cases. We have to do it ourselves.
+ * Otherwise we run into trouble when SWIOTLB is forced.
+ */
+static void pvscsi_patch_sense(struct scsi_cmnd *cmd)
+{
+ if (cmd->sense_buffer)
+ cmd->sense_buffer[0] = 0;
+}
+
+static void pvscsi_unmap_buffers(const struct pvscsi_adapter *adapter,
+ struct pvscsi_ctx *ctx)
+{
+ struct scsi_cmnd *cmd;
+ unsigned bufflen;
+
+ cmd = ctx->cmd;
+ bufflen = scsi_bufflen(cmd);
+
+ if (bufflen != 0) {
+ unsigned count = scsi_sg_count(cmd);
+
+ if (count != 0) {
+ scsi_dma_unmap(cmd);
+ if (ctx->sglPA) {
+ dma_unmap_single(&adapter->dev->dev, ctx->sglPA,
+ SGL_SIZE, DMA_TO_DEVICE);
+ ctx->sglPA = 0;
+ }
+ } else
+ dma_unmap_single(&adapter->dev->dev, ctx->dataPA,
+ bufflen, cmd->sc_data_direction);
+ }
+ if (cmd->sense_buffer)
+ dma_unmap_single(&adapter->dev->dev, ctx->sensePA,
+ SCSI_SENSE_BUFFERSIZE, DMA_FROM_DEVICE);
+}
+
+static int pvscsi_allocate_rings(struct pvscsi_adapter *adapter)
+{
+ adapter->rings_state = dma_alloc_coherent(&adapter->dev->dev, PAGE_SIZE,
+ &adapter->ringStatePA, GFP_KERNEL);
+ if (!adapter->rings_state)
+ return -ENOMEM;
+
+ adapter->req_pages = min(PVSCSI_MAX_NUM_PAGES_REQ_RING,
+ pvscsi_ring_pages);
+ adapter->req_depth = adapter->req_pages
+ * PVSCSI_MAX_NUM_REQ_ENTRIES_PER_PAGE;
+ adapter->req_ring = dma_alloc_coherent(&adapter->dev->dev,
+ adapter->req_pages * PAGE_SIZE, &adapter->reqRingPA,
+ GFP_KERNEL);
+ if (!adapter->req_ring)
+ return -ENOMEM;
+
+ adapter->cmp_pages = min(PVSCSI_MAX_NUM_PAGES_CMP_RING,
+ pvscsi_ring_pages);
+ adapter->cmp_ring = dma_alloc_coherent(&adapter->dev->dev,
+ adapter->cmp_pages * PAGE_SIZE, &adapter->cmpRingPA,
+ GFP_KERNEL);
+ if (!adapter->cmp_ring)
+ return -ENOMEM;
+
+ BUG_ON(!IS_ALIGNED(adapter->ringStatePA, PAGE_SIZE));
+ BUG_ON(!IS_ALIGNED(adapter->reqRingPA, PAGE_SIZE));
+ BUG_ON(!IS_ALIGNED(adapter->cmpRingPA, PAGE_SIZE));
+
+ if (!adapter->use_msg)
+ return 0;
+
+ adapter->msg_pages = min(PVSCSI_MAX_NUM_PAGES_MSG_RING,
+ pvscsi_msg_ring_pages);
+ adapter->msg_ring = dma_alloc_coherent(&adapter->dev->dev,
+ adapter->msg_pages * PAGE_SIZE, &adapter->msgRingPA,
+ GFP_KERNEL);
+ if (!adapter->msg_ring)
+ return -ENOMEM;
+ BUG_ON(!IS_ALIGNED(adapter->msgRingPA, PAGE_SIZE));
+
+ return 0;
+}
+
+static void pvscsi_setup_all_rings(const struct pvscsi_adapter *adapter)
+{
+ struct PVSCSICmdDescSetupRings cmd = { 0 };
+ dma_addr_t base;
+ unsigned i;
+
+ cmd.ringsStatePPN = adapter->ringStatePA >> PAGE_SHIFT;
+ cmd.reqRingNumPages = adapter->req_pages;
+ cmd.cmpRingNumPages = adapter->cmp_pages;
+
+ base = adapter->reqRingPA;
+ for (i = 0; i < adapter->req_pages; i++) {
+ cmd.reqRingPPNs[i] = base >> PAGE_SHIFT;
+ base += PAGE_SIZE;
+ }
+
+ base = adapter->cmpRingPA;
+ for (i = 0; i < adapter->cmp_pages; i++) {
+ cmd.cmpRingPPNs[i] = base >> PAGE_SHIFT;
+ base += PAGE_SIZE;
+ }
+
+ memset(adapter->rings_state, 0, PAGE_SIZE);
+ memset(adapter->req_ring, 0, adapter->req_pages * PAGE_SIZE);
+ memset(adapter->cmp_ring, 0, adapter->cmp_pages * PAGE_SIZE);
+
+ pvscsi_write_cmd_desc(adapter, PVSCSI_CMD_SETUP_RINGS,
+ &cmd, sizeof(cmd));
+
+ if (adapter->use_msg) {
+ struct PVSCSICmdDescSetupMsgRing cmd_msg = { 0 };
+
+ cmd_msg.numPages = adapter->msg_pages;
+
+ base = adapter->msgRingPA;
+ for (i = 0; i < adapter->msg_pages; i++) {
+ cmd_msg.ringPPNs[i] = base >> PAGE_SHIFT;
+ base += PAGE_SIZE;
+ }
+ memset(adapter->msg_ring, 0, adapter->msg_pages * PAGE_SIZE);
+
+ pvscsi_write_cmd_desc(adapter, PVSCSI_CMD_SETUP_MSG_RING,
+ &cmd_msg, sizeof(cmd_msg));
+ }
+}
+
+static int pvscsi_change_queue_depth(struct scsi_device *sdev, int qdepth)
+{
+ if (!sdev->tagged_supported)
+ qdepth = 1;
+ return scsi_change_queue_depth(sdev, qdepth);
+}
+
+/*
+ * Pull a completion descriptor off and pass the completion back
+ * to the SCSI mid layer.
+ */
+static void pvscsi_complete_request(struct pvscsi_adapter *adapter,
+ const struct PVSCSIRingCmpDesc *e)
+{
+ struct pvscsi_ctx *ctx;
+ struct scsi_cmnd *cmd;
+ struct completion *abort_cmp;
+ u32 btstat = e->hostStatus;
+ u32 sdstat = e->scsiStatus;
+
+ ctx = pvscsi_get_context(adapter, e->context);
+ cmd = ctx->cmd;
+ abort_cmp = ctx->abort_cmp;
+ pvscsi_unmap_buffers(adapter, ctx);
+ if (sdstat != SAM_STAT_CHECK_CONDITION)
+ pvscsi_patch_sense(cmd);
+ pvscsi_release_context(adapter, ctx);
+ if (abort_cmp) {
+ /*
+ * The command was requested to be aborted. Just signal that
+ * the request completed and swallow the actual cmd completion
+ * here. The abort handler will post a completion for this
+ * command indicating that it got successfully aborted.
+ */
+ complete(abort_cmp);
+ return;
+ }
+
+ cmd->result = 0;
+ if (sdstat != SAM_STAT_GOOD &&
+ (btstat == BTSTAT_SUCCESS ||
+ btstat == BTSTAT_LINKED_COMMAND_COMPLETED ||
+ btstat == BTSTAT_LINKED_COMMAND_COMPLETED_WITH_FLAG)) {
+ if (sdstat == SAM_STAT_COMMAND_TERMINATED) {
+ cmd->result = (DID_RESET << 16);
+ } else {
+ cmd->result = (DID_OK << 16) | sdstat;
+ }
+ } else
+ switch (btstat) {
+ case BTSTAT_SUCCESS:
+ case BTSTAT_LINKED_COMMAND_COMPLETED:
+ case BTSTAT_LINKED_COMMAND_COMPLETED_WITH_FLAG:
+ /*
+ * Commands like INQUIRY may transfer less data than
+ * requested by the initiator via bufflen. Set residual
+ * count to make upper layer aware of the actual amount
+ * of data returned. There are cases when controller
+ * returns zero dataLen with non zero data - do not set
+ * residual count in that case.
+ */
+ if (e->dataLen && (e->dataLen < scsi_bufflen(cmd)))
+ scsi_set_resid(cmd, scsi_bufflen(cmd) - e->dataLen);
+ cmd->result = (DID_OK << 16);
+ break;
+
+ case BTSTAT_DATARUN:
+ case BTSTAT_DATA_UNDERRUN:
+ /* Report residual data in underruns */
+ scsi_set_resid(cmd, scsi_bufflen(cmd) - e->dataLen);
+ cmd->result = (DID_ERROR << 16);
+ break;
+
+ case BTSTAT_SELTIMEO:
+ /* Our emulation returns this for non-connected devs */
+ cmd->result = (DID_BAD_TARGET << 16);
+ break;
+
+ case BTSTAT_LUNMISMATCH:
+ case BTSTAT_TAGREJECT:
+ case BTSTAT_BADMSG:
+ case BTSTAT_HAHARDWARE:
+ case BTSTAT_INVPHASE:
+ case BTSTAT_HATIMEOUT:
+ case BTSTAT_NORESPONSE:
+ case BTSTAT_DISCONNECT:
+ case BTSTAT_HASOFTWARE:
+ case BTSTAT_BUSFREE:
+ case BTSTAT_SENSFAILED:
+ cmd->result |= (DID_ERROR << 16);
+ break;
+
+ case BTSTAT_SENTRST:
+ case BTSTAT_RECVRST:
+ case BTSTAT_BUSRESET:
+ cmd->result = (DID_RESET << 16);
+ break;
+
+ case BTSTAT_ABORTQUEUE:
+ cmd->result = (DID_BUS_BUSY << 16);
+ break;
+
+ case BTSTAT_SCSIPARITY:
+ cmd->result = (DID_PARITY << 16);
+ break;
+
+ default:
+ cmd->result = (DID_ERROR << 16);
+ scmd_printk(KERN_DEBUG, cmd,
+ "Unknown completion status: 0x%x\n",
+ btstat);
+ }
+
+ dev_dbg(&cmd->device->sdev_gendev,
+ "cmd=%p %x ctx=%p result=0x%x status=0x%x,%x\n",
+ cmd, cmd->cmnd[0], ctx, cmd->result, btstat, sdstat);
+
+ scsi_done(cmd);
+}
+
+/*
+ * barrier usage : Since the PVSCSI device is emulated, there could be cases
+ * where we may want to serialize some accesses between the driver and the
+ * emulation layer. We use compiler barriers instead of the more expensive
+ * memory barriers because PVSCSI is only supported on X86 which has strong
+ * memory access ordering.
+ */
+static void pvscsi_process_completion_ring(struct pvscsi_adapter *adapter)
+{
+ struct PVSCSIRingsState *s = adapter->rings_state;
+ struct PVSCSIRingCmpDesc *ring = adapter->cmp_ring;
+ u32 cmp_entries = s->cmpNumEntriesLog2;
+
+ while (s->cmpConsIdx != s->cmpProdIdx) {
+ struct PVSCSIRingCmpDesc *e = ring + (s->cmpConsIdx &
+ MASK(cmp_entries));
+ /*
+ * This barrier() ensures that *e is not dereferenced while
+ * the device emulation still writes data into the slot.
+ * Since the device emulation advances s->cmpProdIdx only after
+ * updating the slot we want to check it first.
+ */
+ barrier();
+ pvscsi_complete_request(adapter, e);
+ /*
+ * This barrier() ensures that compiler doesn't reorder write
+ * to s->cmpConsIdx before the read of (*e) inside
+ * pvscsi_complete_request. Otherwise, device emulation may
+ * overwrite *e before we had a chance to read it.
+ */
+ barrier();
+ s->cmpConsIdx++;
+ }
+}
+
+/*
+ * Translate a Linux SCSI request into a request ring entry.
+ */
+static int pvscsi_queue_ring(struct pvscsi_adapter *adapter,
+ struct pvscsi_ctx *ctx, struct scsi_cmnd *cmd)
+{
+ struct PVSCSIRingsState *s;
+ struct PVSCSIRingReqDesc *e;
+ struct scsi_device *sdev;
+ u32 req_entries;
+
+ s = adapter->rings_state;
+ sdev = cmd->device;
+ req_entries = s->reqNumEntriesLog2;
+
+ /*
+ * If this condition holds, we might have room on the request ring, but
+ * we might not have room on the completion ring for the response.
+ * However, we have already ruled out this possibility - we would not
+ * have successfully allocated a context if it were true, since we only
+ * have one context per request entry. Check for it anyway, since it
+ * would be a serious bug.
+ */
+ if (s->reqProdIdx - s->cmpConsIdx >= 1 << req_entries) {
+ scmd_printk(KERN_ERR, cmd, "vmw_pvscsi: "
+ "ring full: reqProdIdx=%d cmpConsIdx=%d\n",
+ s->reqProdIdx, s->cmpConsIdx);
+ return -1;
+ }
+
+ e = adapter->req_ring + (s->reqProdIdx & MASK(req_entries));
+
+ e->bus = sdev->channel;
+ e->target = sdev->id;
+ memset(e->lun, 0, sizeof(e->lun));
+ e->lun[1] = sdev->lun;
+
+ if (cmd->sense_buffer) {
+ ctx->sensePA = dma_map_single(&adapter->dev->dev,
+ cmd->sense_buffer, SCSI_SENSE_BUFFERSIZE,
+ DMA_FROM_DEVICE);
+ if (dma_mapping_error(&adapter->dev->dev, ctx->sensePA)) {
+ scmd_printk(KERN_DEBUG, cmd,
+ "vmw_pvscsi: Failed to map sense buffer for DMA.\n");
+ ctx->sensePA = 0;
+ return -ENOMEM;
+ }
+ e->senseAddr = ctx->sensePA;
+ e->senseLen = SCSI_SENSE_BUFFERSIZE;
+ } else {
+ e->senseLen = 0;
+ e->senseAddr = 0;
+ }
+ e->cdbLen = cmd->cmd_len;
+ e->vcpuHint = smp_processor_id();
+ memcpy(e->cdb, cmd->cmnd, e->cdbLen);
+
+ e->tag = SIMPLE_QUEUE_TAG;
+
+ if (cmd->sc_data_direction == DMA_FROM_DEVICE)
+ e->flags = PVSCSI_FLAG_CMD_DIR_TOHOST;
+ else if (cmd->sc_data_direction == DMA_TO_DEVICE)
+ e->flags = PVSCSI_FLAG_CMD_DIR_TODEVICE;
+ else if (cmd->sc_data_direction == DMA_NONE)
+ e->flags = PVSCSI_FLAG_CMD_DIR_NONE;
+ else
+ e->flags = 0;
+
+ if (pvscsi_map_buffers(adapter, ctx, cmd, e) != 0) {
+ if (cmd->sense_buffer) {
+ dma_unmap_single(&adapter->dev->dev, ctx->sensePA,
+ SCSI_SENSE_BUFFERSIZE,
+ DMA_FROM_DEVICE);
+ ctx->sensePA = 0;
+ }
+ return -ENOMEM;
+ }
+
+ e->context = pvscsi_map_context(adapter, ctx);
+
+ barrier();
+
+ s->reqProdIdx++;
+
+ return 0;
+}
+
+static int pvscsi_queue_lck(struct scsi_cmnd *cmd)
+{
+ struct Scsi_Host *host = cmd->device->host;
+ struct pvscsi_adapter *adapter = shost_priv(host);
+ struct pvscsi_ctx *ctx;
+ unsigned long flags;
+ unsigned char op;
+
+ spin_lock_irqsave(&adapter->hw_lock, flags);
+
+ ctx = pvscsi_acquire_context(adapter, cmd);
+ if (!ctx || pvscsi_queue_ring(adapter, ctx, cmd) != 0) {
+ if (ctx)
+ pvscsi_release_context(adapter, ctx);
+ spin_unlock_irqrestore(&adapter->hw_lock, flags);
+ return SCSI_MLQUEUE_HOST_BUSY;
+ }
+
+ op = cmd->cmnd[0];
+
+ dev_dbg(&cmd->device->sdev_gendev,
+ "queued cmd %p, ctx %p, op=%x\n", cmd, ctx, op);
+
+ spin_unlock_irqrestore(&adapter->hw_lock, flags);
+
+ pvscsi_kick_io(adapter, op);
+
+ return 0;
+}
+
+static DEF_SCSI_QCMD(pvscsi_queue)
+
+static int pvscsi_abort(struct scsi_cmnd *cmd)
+{
+ struct pvscsi_adapter *adapter = shost_priv(cmd->device->host);
+ struct pvscsi_ctx *ctx;
+ unsigned long flags;
+ int result = SUCCESS;
+ DECLARE_COMPLETION_ONSTACK(abort_cmp);
+ int done;
+
+ scmd_printk(KERN_DEBUG, cmd, "task abort on host %u, %p\n",
+ adapter->host->host_no, cmd);
+
+ spin_lock_irqsave(&adapter->hw_lock, flags);
+
+ /*
+ * Poll the completion ring first - we might be trying to abort
+ * a command that is waiting to be dispatched in the completion ring.
+ */
+ pvscsi_process_completion_ring(adapter);
+
+ /*
+ * If there is no context for the command, it either already succeeded
+ * or else was never properly issued. Not our problem.
+ */
+ ctx = pvscsi_find_context(adapter, cmd);
+ if (!ctx) {
+ scmd_printk(KERN_DEBUG, cmd, "Failed to abort cmd %p\n", cmd);
+ goto out;
+ }
+
+ /*
+ * Mark that the command has been requested to be aborted and issue
+ * the abort.
+ */
+ ctx->abort_cmp = &abort_cmp;
+
+ pvscsi_abort_cmd(adapter, ctx);
+ spin_unlock_irqrestore(&adapter->hw_lock, flags);
+ /* Wait for 2 secs for the completion. */
+ done = wait_for_completion_timeout(&abort_cmp, msecs_to_jiffies(2000));
+ spin_lock_irqsave(&adapter->hw_lock, flags);
+
+ if (!done) {
+ /*
+ * Failed to abort the command, unmark the fact that it
+ * was requested to be aborted.
+ */
+ ctx->abort_cmp = NULL;
+ result = FAILED;
+ scmd_printk(KERN_DEBUG, cmd,
+ "Failed to get completion for aborted cmd %p\n",
+ cmd);
+ goto out;
+ }
+
+ /*
+ * Successfully aborted the command.
+ */
+ cmd->result = (DID_ABORT << 16);
+ scsi_done(cmd);
+
+out:
+ spin_unlock_irqrestore(&adapter->hw_lock, flags);
+ return result;
+}
+
+/*
+ * Abort all outstanding requests. This is only safe to use if the completion
+ * ring will never be walked again or the device has been reset, because it
+ * destroys the 1-1 mapping between context field passed to emulation and our
+ * request structure.
+ */
+static void pvscsi_reset_all(struct pvscsi_adapter *adapter)
+{
+ unsigned i;
+
+ for (i = 0; i < adapter->req_depth; i++) {
+ struct pvscsi_ctx *ctx = &adapter->cmd_map[i];
+ struct scsi_cmnd *cmd = ctx->cmd;
+ if (cmd) {
+ scmd_printk(KERN_ERR, cmd,
+ "Forced reset on cmd %p\n", cmd);
+ pvscsi_unmap_buffers(adapter, ctx);
+ pvscsi_patch_sense(cmd);
+ pvscsi_release_context(adapter, ctx);
+ cmd->result = (DID_RESET << 16);
+ scsi_done(cmd);
+ }
+ }
+}
+
+static int pvscsi_host_reset(struct scsi_cmnd *cmd)
+{
+ struct Scsi_Host *host = cmd->device->host;
+ struct pvscsi_adapter *adapter = shost_priv(host);
+ unsigned long flags;
+ bool use_msg;
+
+ scmd_printk(KERN_INFO, cmd, "SCSI Host reset\n");
+
+ spin_lock_irqsave(&adapter->hw_lock, flags);
+
+ use_msg = adapter->use_msg;
+
+ if (use_msg) {
+ adapter->use_msg = false;
+ spin_unlock_irqrestore(&adapter->hw_lock, flags);
+
+ /*
+ * Now that we know that the ISR won't add more work on the
+ * workqueue we can safely flush any outstanding work.
+ */
+ flush_workqueue(adapter->workqueue);
+ spin_lock_irqsave(&adapter->hw_lock, flags);
+ }
+
+ /*
+ * We're going to tear down the entire ring structure and set it back
+ * up, so stalling new requests until all completions are flushed and
+ * the rings are back in place.
+ */
+
+ pvscsi_process_request_ring(adapter);
+
+ ll_adapter_reset(adapter);
+
+ /*
+ * Now process any completions. Note we do this AFTER adapter reset,
+ * which is strange, but stops races where completions get posted
+ * between processing the ring and issuing the reset. The backend will
+ * not touch the ring memory after reset, so the immediately pre-reset
+ * completion ring state is still valid.
+ */
+ pvscsi_process_completion_ring(adapter);
+
+ pvscsi_reset_all(adapter);
+ adapter->use_msg = use_msg;
+ pvscsi_setup_all_rings(adapter);
+ pvscsi_unmask_intr(adapter);
+
+ spin_unlock_irqrestore(&adapter->hw_lock, flags);
+
+ return SUCCESS;
+}
+
+static int pvscsi_bus_reset(struct scsi_cmnd *cmd)
+{
+ struct Scsi_Host *host = cmd->device->host;
+ struct pvscsi_adapter *adapter = shost_priv(host);
+ unsigned long flags;
+
+ scmd_printk(KERN_INFO, cmd, "SCSI Bus reset\n");
+
+ /*
+ * We don't want to queue new requests for this bus after
+ * flushing all pending requests to emulation, since new
+ * requests could then sneak in during this bus reset phase,
+ * so take the lock now.
+ */
+ spin_lock_irqsave(&adapter->hw_lock, flags);
+
+ pvscsi_process_request_ring(adapter);
+ ll_bus_reset(adapter);
+ pvscsi_process_completion_ring(adapter);
+
+ spin_unlock_irqrestore(&adapter->hw_lock, flags);
+
+ return SUCCESS;
+}
+
+static int pvscsi_device_reset(struct scsi_cmnd *cmd)
+{
+ struct Scsi_Host *host = cmd->device->host;
+ struct pvscsi_adapter *adapter = shost_priv(host);
+ unsigned long flags;
+
+ scmd_printk(KERN_INFO, cmd, "SCSI device reset on scsi%u:%u\n",
+ host->host_no, cmd->device->id);
+
+ /*
+ * We don't want to queue new requests for this device after flushing
+ * all pending requests to emulation, since new requests could then
+ * sneak in during this device reset phase, so take the lock now.
+ */
+ spin_lock_irqsave(&adapter->hw_lock, flags);
+
+ pvscsi_process_request_ring(adapter);
+ ll_device_reset(adapter, cmd->device->id);
+ pvscsi_process_completion_ring(adapter);
+
+ spin_unlock_irqrestore(&adapter->hw_lock, flags);
+
+ return SUCCESS;
+}
+
+static struct scsi_host_template pvscsi_template;
+
+static const char *pvscsi_info(struct Scsi_Host *host)
+{
+ struct pvscsi_adapter *adapter = shost_priv(host);
+ static char buf[256];
+
+ sprintf(buf, "VMware PVSCSI storage adapter rev %d, req/cmp/msg rings: "
+ "%u/%u/%u pages, cmd_per_lun=%u", adapter->rev,
+ adapter->req_pages, adapter->cmp_pages, adapter->msg_pages,
+ pvscsi_template.cmd_per_lun);
+
+ return buf;
+}
+
+static struct scsi_host_template pvscsi_template = {
+ .module = THIS_MODULE,
+ .name = "VMware PVSCSI Host Adapter",
+ .proc_name = "vmw_pvscsi",
+ .info = pvscsi_info,
+ .queuecommand = pvscsi_queue,
+ .this_id = -1,
+ .sg_tablesize = PVSCSI_MAX_NUM_SG_ENTRIES_PER_SEGMENT,
+ .dma_boundary = UINT_MAX,
+ .max_sectors = 0xffff,
+ .change_queue_depth = pvscsi_change_queue_depth,
+ .eh_abort_handler = pvscsi_abort,
+ .eh_device_reset_handler = pvscsi_device_reset,
+ .eh_bus_reset_handler = pvscsi_bus_reset,
+ .eh_host_reset_handler = pvscsi_host_reset,
+};
+
+static void pvscsi_process_msg(const struct pvscsi_adapter *adapter,
+ const struct PVSCSIRingMsgDesc *e)
+{
+ struct PVSCSIRingsState *s = adapter->rings_state;
+ struct Scsi_Host *host = adapter->host;
+ struct scsi_device *sdev;
+
+ printk(KERN_INFO "vmw_pvscsi: msg type: 0x%x - MSG RING: %u/%u (%u) \n",
+ e->type, s->msgProdIdx, s->msgConsIdx, s->msgNumEntriesLog2);
+
+ BUILD_BUG_ON(PVSCSI_MSG_LAST != 2);
+
+ if (e->type == PVSCSI_MSG_DEV_ADDED) {
+ struct PVSCSIMsgDescDevStatusChanged *desc;
+ desc = (struct PVSCSIMsgDescDevStatusChanged *)e;
+
+ printk(KERN_INFO
+ "vmw_pvscsi: msg: device added at scsi%u:%u:%u\n",
+ desc->bus, desc->target, desc->lun[1]);
+
+ if (!scsi_host_get(host))
+ return;
+
+ sdev = scsi_device_lookup(host, desc->bus, desc->target,
+ desc->lun[1]);
+ if (sdev) {
+ printk(KERN_INFO "vmw_pvscsi: device already exists\n");
+ scsi_device_put(sdev);
+ } else
+ scsi_add_device(adapter->host, desc->bus,
+ desc->target, desc->lun[1]);
+
+ scsi_host_put(host);
+ } else if (e->type == PVSCSI_MSG_DEV_REMOVED) {
+ struct PVSCSIMsgDescDevStatusChanged *desc;
+ desc = (struct PVSCSIMsgDescDevStatusChanged *)e;
+
+ printk(KERN_INFO
+ "vmw_pvscsi: msg: device removed at scsi%u:%u:%u\n",
+ desc->bus, desc->target, desc->lun[1]);
+
+ if (!scsi_host_get(host))
+ return;
+
+ sdev = scsi_device_lookup(host, desc->bus, desc->target,
+ desc->lun[1]);
+ if (sdev) {
+ scsi_remove_device(sdev);
+ scsi_device_put(sdev);
+ } else
+ printk(KERN_INFO
+ "vmw_pvscsi: failed to lookup scsi%u:%u:%u\n",
+ desc->bus, desc->target, desc->lun[1]);
+
+ scsi_host_put(host);
+ }
+}
+
+static int pvscsi_msg_pending(const struct pvscsi_adapter *adapter)
+{
+ struct PVSCSIRingsState *s = adapter->rings_state;
+
+ return s->msgProdIdx != s->msgConsIdx;
+}
+
+static void pvscsi_process_msg_ring(const struct pvscsi_adapter *adapter)
+{
+ struct PVSCSIRingsState *s = adapter->rings_state;
+ struct PVSCSIRingMsgDesc *ring = adapter->msg_ring;
+ u32 msg_entries = s->msgNumEntriesLog2;
+
+ while (pvscsi_msg_pending(adapter)) {
+ struct PVSCSIRingMsgDesc *e = ring + (s->msgConsIdx &
+ MASK(msg_entries));
+
+ barrier();
+ pvscsi_process_msg(adapter, e);
+ barrier();
+ s->msgConsIdx++;
+ }
+}
+
+static void pvscsi_msg_workqueue_handler(struct work_struct *data)
+{
+ struct pvscsi_adapter *adapter;
+
+ adapter = container_of(data, struct pvscsi_adapter, work);
+
+ pvscsi_process_msg_ring(adapter);
+}
+
+static int pvscsi_setup_msg_workqueue(struct pvscsi_adapter *adapter)
+{
+ char name[32];
+
+ if (!pvscsi_use_msg)
+ return 0;
+
+ pvscsi_reg_write(adapter, PVSCSI_REG_OFFSET_COMMAND,
+ PVSCSI_CMD_SETUP_MSG_RING);
+
+ if (pvscsi_reg_read(adapter, PVSCSI_REG_OFFSET_COMMAND_STATUS) == -1)
+ return 0;
+
+ snprintf(name, sizeof(name),
+ "vmw_pvscsi_wq_%u", adapter->host->host_no);
+
+ adapter->workqueue = create_singlethread_workqueue(name);
+ if (!adapter->workqueue) {
+ printk(KERN_ERR "vmw_pvscsi: failed to create work queue\n");
+ return 0;
+ }
+ INIT_WORK(&adapter->work, pvscsi_msg_workqueue_handler);
+
+ return 1;
+}
+
+static bool pvscsi_setup_req_threshold(struct pvscsi_adapter *adapter,
+ bool enable)
+{
+ u32 val;
+
+ if (!pvscsi_use_req_threshold)
+ return false;
+
+ pvscsi_reg_write(adapter, PVSCSI_REG_OFFSET_COMMAND,
+ PVSCSI_CMD_SETUP_REQCALLTHRESHOLD);
+ val = pvscsi_reg_read(adapter, PVSCSI_REG_OFFSET_COMMAND_STATUS);
+ if (val == -1) {
+ printk(KERN_INFO "vmw_pvscsi: device does not support req_threshold\n");
+ return false;
+ } else {
+ struct PVSCSICmdDescSetupReqCall cmd_msg = { 0 };
+ cmd_msg.enable = enable;
+ printk(KERN_INFO
+ "vmw_pvscsi: %sabling reqCallThreshold\n",
+ enable ? "en" : "dis");
+ pvscsi_write_cmd_desc(adapter,
+ PVSCSI_CMD_SETUP_REQCALLTHRESHOLD,
+ &cmd_msg, sizeof(cmd_msg));
+ return pvscsi_reg_read(adapter,
+ PVSCSI_REG_OFFSET_COMMAND_STATUS) != 0;
+ }
+}
+
+static irqreturn_t pvscsi_isr(int irq, void *devp)
+{
+ struct pvscsi_adapter *adapter = devp;
+ unsigned long flags;
+
+ spin_lock_irqsave(&adapter->hw_lock, flags);
+ pvscsi_process_completion_ring(adapter);
+ if (adapter->use_msg && pvscsi_msg_pending(adapter))
+ queue_work(adapter->workqueue, &adapter->work);
+ spin_unlock_irqrestore(&adapter->hw_lock, flags);
+
+ return IRQ_HANDLED;
+}
+
+static irqreturn_t pvscsi_shared_isr(int irq, void *devp)
+{
+ struct pvscsi_adapter *adapter = devp;
+ u32 val = pvscsi_read_intr_status(adapter);
+
+ if (!(val & PVSCSI_INTR_ALL_SUPPORTED))
+ return IRQ_NONE;
+ pvscsi_write_intr_status(devp, val);
+ return pvscsi_isr(irq, devp);
+}
+
+static void pvscsi_free_sgls(const struct pvscsi_adapter *adapter)
+{
+ struct pvscsi_ctx *ctx = adapter->cmd_map;
+ unsigned i;
+
+ for (i = 0; i < adapter->req_depth; ++i, ++ctx)
+ free_pages((unsigned long)ctx->sgl, get_order(SGL_SIZE));
+}
+
+static void pvscsi_shutdown_intr(struct pvscsi_adapter *adapter)
+{
+ free_irq(pci_irq_vector(adapter->dev, 0), adapter);
+ pci_free_irq_vectors(adapter->dev);
+}
+
+static void pvscsi_release_resources(struct pvscsi_adapter *adapter)
+{
+ if (adapter->workqueue)
+ destroy_workqueue(adapter->workqueue);
+
+ if (adapter->mmioBase)
+ pci_iounmap(adapter->dev, adapter->mmioBase);
+
+ pci_release_regions(adapter->dev);
+
+ if (adapter->cmd_map) {
+ pvscsi_free_sgls(adapter);
+ kfree(adapter->cmd_map);
+ }
+
+ if (adapter->rings_state)
+ dma_free_coherent(&adapter->dev->dev, PAGE_SIZE,
+ adapter->rings_state, adapter->ringStatePA);
+
+ if (adapter->req_ring)
+ dma_free_coherent(&adapter->dev->dev,
+ adapter->req_pages * PAGE_SIZE,
+ adapter->req_ring, adapter->reqRingPA);
+
+ if (adapter->cmp_ring)
+ dma_free_coherent(&adapter->dev->dev,
+ adapter->cmp_pages * PAGE_SIZE,
+ adapter->cmp_ring, adapter->cmpRingPA);
+
+ if (adapter->msg_ring)
+ dma_free_coherent(&adapter->dev->dev,
+ adapter->msg_pages * PAGE_SIZE,
+ adapter->msg_ring, adapter->msgRingPA);
+}
+
+/*
+ * Allocate scatter gather lists.
+ *
+ * These are statically allocated. Trying to be clever was not worth it.
+ *
+ * Dynamic allocation can fail, and we can't go deep into the memory
+ * allocator, since we're a SCSI driver, and trying too hard to allocate
+ * memory might generate disk I/O. We also don't want to fail disk I/O
+ * in that case because we can't get an allocation - the I/O could be
+ * trying to swap out data to free memory. Since that is pathological,
+ * just use a statically allocated scatter list.
+ *
+ */
+static int pvscsi_allocate_sg(struct pvscsi_adapter *adapter)
+{
+ struct pvscsi_ctx *ctx;
+ int i;
+
+ ctx = adapter->cmd_map;
+ BUILD_BUG_ON(sizeof(struct pvscsi_sg_list) > SGL_SIZE);
+
+ for (i = 0; i < adapter->req_depth; ++i, ++ctx) {
+ ctx->sgl = (void *)__get_free_pages(GFP_KERNEL,
+ get_order(SGL_SIZE));
+ ctx->sglPA = 0;
+ BUG_ON(!IS_ALIGNED(((unsigned long)ctx->sgl), PAGE_SIZE));
+ if (!ctx->sgl) {
+ for (; i >= 0; --i, --ctx) {
+ free_pages((unsigned long)ctx->sgl,
+ get_order(SGL_SIZE));
+ ctx->sgl = NULL;
+ }
+ return -ENOMEM;
+ }
+ }
+
+ return 0;
+}
+
+/*
+ * Query the device, fetch the config info and return the
+ * maximum number of targets on the adapter. In case of
+ * failure due to any reason return default i.e. 16.
+ */
+static u32 pvscsi_get_max_targets(struct pvscsi_adapter *adapter)
+{
+ struct PVSCSICmdDescConfigCmd cmd;
+ struct PVSCSIConfigPageHeader *header;
+ struct device *dev;
+ dma_addr_t configPagePA;
+ void *config_page;
+ u32 numPhys = 16;
+
+ dev = pvscsi_dev(adapter);
+ config_page = dma_alloc_coherent(&adapter->dev->dev, PAGE_SIZE,
+ &configPagePA, GFP_KERNEL);
+ if (!config_page) {
+ dev_warn(dev, "vmw_pvscsi: failed to allocate memory for config page\n");
+ goto exit;
+ }
+ BUG_ON(configPagePA & ~PAGE_MASK);
+
+ /* Fetch config info from the device. */
+ cmd.configPageAddress = ((u64)PVSCSI_CONFIG_CONTROLLER_ADDRESS) << 32;
+ cmd.configPageNum = PVSCSI_CONFIG_PAGE_CONTROLLER;
+ cmd.cmpAddr = configPagePA;
+ cmd._pad = 0;
+
+ /*
+ * Mark the completion page header with error values. If the device
+ * completes the command successfully, it sets the status values to
+ * indicate success.
+ */
+ header = config_page;
+ header->hostStatus = BTSTAT_INVPARAM;
+ header->scsiStatus = SDSTAT_CHECK;
+
+ pvscsi_write_cmd_desc(adapter, PVSCSI_CMD_CONFIG, &cmd, sizeof cmd);
+
+ if (header->hostStatus == BTSTAT_SUCCESS &&
+ header->scsiStatus == SDSTAT_GOOD) {
+ struct PVSCSIConfigPageController *config;
+
+ config = config_page;
+ numPhys = config->numPhys;
+ } else
+ dev_warn(dev, "vmw_pvscsi: PVSCSI_CMD_CONFIG failed. hostStatus = 0x%x, scsiStatus = 0x%x\n",
+ header->hostStatus, header->scsiStatus);
+ dma_free_coherent(&adapter->dev->dev, PAGE_SIZE, config_page,
+ configPagePA);
+exit:
+ return numPhys;
+}
+
+static int pvscsi_probe(struct pci_dev *pdev, const struct pci_device_id *id)
+{
+ unsigned int irq_flag = PCI_IRQ_MSIX | PCI_IRQ_MSI | PCI_IRQ_LEGACY;
+ struct pvscsi_adapter *adapter;
+ struct pvscsi_adapter adapter_temp;
+ struct Scsi_Host *host = NULL;
+ unsigned int i;
+ int error;
+ u32 max_id;
+
+ error = -ENODEV;
+
+ if (pci_enable_device(pdev))
+ return error;
+
+ if (!dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(64))) {
+ printk(KERN_INFO "vmw_pvscsi: using 64bit dma\n");
+ } else if (!dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32))) {
+ printk(KERN_INFO "vmw_pvscsi: using 32bit dma\n");
+ } else {
+ printk(KERN_ERR "vmw_pvscsi: failed to set DMA mask\n");
+ goto out_disable_device;
+ }
+
+ /*
+ * Let's use a temp pvscsi_adapter struct until we find the number of
+ * targets on the adapter, after that we will switch to the real
+ * allocated struct.
+ */
+ adapter = &adapter_temp;
+ memset(adapter, 0, sizeof(*adapter));
+ adapter->dev = pdev;
+ adapter->rev = pdev->revision;
+
+ if (pci_request_regions(pdev, "vmw_pvscsi")) {
+ printk(KERN_ERR "vmw_pvscsi: pci memory selection failed\n");
+ goto out_disable_device;
+ }
+
+ for (i = 0; i < DEVICE_COUNT_RESOURCE; i++) {
+ if ((pci_resource_flags(pdev, i) & PCI_BASE_ADDRESS_SPACE_IO))
+ continue;
+
+ if (pci_resource_len(pdev, i) < PVSCSI_MEM_SPACE_SIZE)
+ continue;
+
+ break;
+ }
+
+ if (i == DEVICE_COUNT_RESOURCE) {
+ printk(KERN_ERR
+ "vmw_pvscsi: adapter has no suitable MMIO region\n");
+ goto out_release_resources_and_disable;
+ }
+
+ adapter->mmioBase = pci_iomap(pdev, i, PVSCSI_MEM_SPACE_SIZE);
+
+ if (!adapter->mmioBase) {
+ printk(KERN_ERR
+ "vmw_pvscsi: can't iomap for BAR %d memsize %lu\n",
+ i, PVSCSI_MEM_SPACE_SIZE);
+ goto out_release_resources_and_disable;
+ }
+
+ pci_set_master(pdev);
+
+ /*
+ * Ask the device for max number of targets before deciding the
+ * default pvscsi_ring_pages value.
+ */
+ max_id = pvscsi_get_max_targets(adapter);
+ printk(KERN_INFO "vmw_pvscsi: max_id: %u\n", max_id);
+
+ if (pvscsi_ring_pages == 0)
+ /*
+ * Set the right default value. Up to 16 it is 8, above it is
+ * max.
+ */
+ pvscsi_ring_pages = (max_id > 16) ?
+ PVSCSI_SETUP_RINGS_MAX_NUM_PAGES :
+ PVSCSI_DEFAULT_NUM_PAGES_PER_RING;
+ printk(KERN_INFO
+ "vmw_pvscsi: setting ring_pages to %d\n",
+ pvscsi_ring_pages);
+
+ pvscsi_template.can_queue =
+ min(PVSCSI_MAX_NUM_PAGES_REQ_RING, pvscsi_ring_pages) *
+ PVSCSI_MAX_NUM_REQ_ENTRIES_PER_PAGE;
+ pvscsi_template.cmd_per_lun =
+ min(pvscsi_template.can_queue, pvscsi_cmd_per_lun);
+ host = scsi_host_alloc(&pvscsi_template, sizeof(struct pvscsi_adapter));
+ if (!host) {
+ printk(KERN_ERR "vmw_pvscsi: failed to allocate host\n");
+ goto out_release_resources_and_disable;
+ }
+
+ /*
+ * Let's use the real pvscsi_adapter struct here onwards.
+ */
+ adapter = shost_priv(host);
+ memset(adapter, 0, sizeof(*adapter));
+ adapter->dev = pdev;
+ adapter->host = host;
+ /*
+ * Copy back what we already have to the allocated adapter struct.
+ */
+ adapter->rev = adapter_temp.rev;
+ adapter->mmioBase = adapter_temp.mmioBase;
+
+ spin_lock_init(&adapter->hw_lock);
+ host->max_channel = 0;
+ host->max_lun = 1;
+ host->max_cmd_len = 16;
+ host->max_id = max_id;
+
+ pci_set_drvdata(pdev, host);
+
+ ll_adapter_reset(adapter);
+
+ adapter->use_msg = pvscsi_setup_msg_workqueue(adapter);
+
+ error = pvscsi_allocate_rings(adapter);
+ if (error) {
+ printk(KERN_ERR "vmw_pvscsi: unable to allocate ring memory\n");
+ goto out_release_resources;
+ }
+
+ /*
+ * From this point on we should reset the adapter if anything goes
+ * wrong.
+ */
+ pvscsi_setup_all_rings(adapter);
+
+ adapter->cmd_map = kcalloc(adapter->req_depth,
+ sizeof(struct pvscsi_ctx), GFP_KERNEL);
+ if (!adapter->cmd_map) {
+ printk(KERN_ERR "vmw_pvscsi: failed to allocate memory.\n");
+ error = -ENOMEM;
+ goto out_reset_adapter;
+ }
+
+ INIT_LIST_HEAD(&adapter->cmd_pool);
+ for (i = 0; i < adapter->req_depth; i++) {
+ struct pvscsi_ctx *ctx = adapter->cmd_map + i;
+ list_add(&ctx->list, &adapter->cmd_pool);
+ }
+
+ error = pvscsi_allocate_sg(adapter);
+ if (error) {
+ printk(KERN_ERR "vmw_pvscsi: unable to allocate s/g table\n");
+ goto out_reset_adapter;
+ }
+
+ if (pvscsi_disable_msix)
+ irq_flag &= ~PCI_IRQ_MSIX;
+ if (pvscsi_disable_msi)
+ irq_flag &= ~PCI_IRQ_MSI;
+
+ error = pci_alloc_irq_vectors(adapter->dev, 1, 1, irq_flag);
+ if (error < 0)
+ goto out_reset_adapter;
+
+ adapter->use_req_threshold = pvscsi_setup_req_threshold(adapter, true);
+ printk(KERN_DEBUG "vmw_pvscsi: driver-based request coalescing %sabled\n",
+ adapter->use_req_threshold ? "en" : "dis");
+
+ if (adapter->dev->msix_enabled || adapter->dev->msi_enabled) {
+ printk(KERN_INFO "vmw_pvscsi: using MSI%s\n",
+ adapter->dev->msix_enabled ? "-X" : "");
+ error = request_irq(pci_irq_vector(pdev, 0), pvscsi_isr,
+ 0, "vmw_pvscsi", adapter);
+ } else {
+ printk(KERN_INFO "vmw_pvscsi: using INTx\n");
+ error = request_irq(pci_irq_vector(pdev, 0), pvscsi_shared_isr,
+ IRQF_SHARED, "vmw_pvscsi", adapter);
+ }
+
+ if (error) {
+ printk(KERN_ERR
+ "vmw_pvscsi: unable to request IRQ: %d\n", error);
+ goto out_reset_adapter;
+ }
+
+ error = scsi_add_host(host, &pdev->dev);
+ if (error) {
+ printk(KERN_ERR
+ "vmw_pvscsi: scsi_add_host failed: %d\n", error);
+ goto out_reset_adapter;
+ }
+
+ dev_info(&pdev->dev, "VMware PVSCSI rev %d host #%u\n",
+ adapter->rev, host->host_no);
+
+ pvscsi_unmask_intr(adapter);
+
+ scsi_scan_host(host);
+
+ return 0;
+
+out_reset_adapter:
+ ll_adapter_reset(adapter);
+out_release_resources:
+ pvscsi_shutdown_intr(adapter);
+ pvscsi_release_resources(adapter);
+ scsi_host_put(host);
+out_disable_device:
+ pci_disable_device(pdev);
+
+ return error;
+
+out_release_resources_and_disable:
+ pvscsi_shutdown_intr(adapter);
+ pvscsi_release_resources(adapter);
+ goto out_disable_device;
+}
+
+static void __pvscsi_shutdown(struct pvscsi_adapter *adapter)
+{
+ pvscsi_mask_intr(adapter);
+
+ if (adapter->workqueue)
+ flush_workqueue(adapter->workqueue);
+
+ pvscsi_shutdown_intr(adapter);
+
+ pvscsi_process_request_ring(adapter);
+ pvscsi_process_completion_ring(adapter);
+ ll_adapter_reset(adapter);
+}
+
+static void pvscsi_shutdown(struct pci_dev *dev)
+{
+ struct Scsi_Host *host = pci_get_drvdata(dev);
+ struct pvscsi_adapter *adapter = shost_priv(host);
+
+ __pvscsi_shutdown(adapter);
+}
+
+static void pvscsi_remove(struct pci_dev *pdev)
+{
+ struct Scsi_Host *host = pci_get_drvdata(pdev);
+ struct pvscsi_adapter *adapter = shost_priv(host);
+
+ scsi_remove_host(host);
+
+ __pvscsi_shutdown(adapter);
+ pvscsi_release_resources(adapter);
+
+ scsi_host_put(host);
+
+ pci_disable_device(pdev);
+}
+
+static struct pci_driver pvscsi_pci_driver = {
+ .name = "vmw_pvscsi",
+ .id_table = pvscsi_pci_tbl,
+ .probe = pvscsi_probe,
+ .remove = pvscsi_remove,
+ .shutdown = pvscsi_shutdown,
+};
+
+static int __init pvscsi_init(void)
+{
+ pr_info("%s - version %s\n",
+ PVSCSI_LINUX_DRIVER_DESC, PVSCSI_DRIVER_VERSION_STRING);
+ return pci_register_driver(&pvscsi_pci_driver);
+}
+
+static void __exit pvscsi_exit(void)
+{
+ pci_unregister_driver(&pvscsi_pci_driver);
+}
+
+module_init(pvscsi_init);
+module_exit(pvscsi_exit);