Greetings to all,
Please find below a patch which adds support for the VMware
paravirtualized SCSI device (PVSCSI).
Kindly consider this for inclusion in the Linux scsi tree. I will be
eager to address all the comments or issues that you may see with the
patch, and get this ready to be accepted in mainline in the 2.6.32
release cycle.
Patch is on top of 2.6.31-rc7.
Thanks.
--
SCSI driver for VMware's virtual HBA.
From: Alok N Kataria <akataria@xxxxxxxxxx>
This is a driver for VMware's paravirtualized SCSI device,
which should improve disk performance for guests running
under control of VMware hypervisors that support such devices.
Signed-off-by: Alok N Kataria <akataria@xxxxxxxxxx>
---
drivers/scsi/Kconfig | 8
drivers/scsi/Makefile | 1
drivers/scsi/pvscsi.c | 1400 +++++++++++++++++++++++++++++++++++++++++++++++++
drivers/scsi/pvscsi.h | 395 ++++++++++++++
4 files changed, 1804 insertions(+), 0 deletions(-)
create mode 100644 drivers/scsi/pvscsi.c
create mode 100644 drivers/scsi/pvscsi.h
diff --git a/drivers/scsi/Kconfig b/drivers/scsi/Kconfig
index 9c23122..8a47981 100644
--- a/drivers/scsi/Kconfig
+++ b/drivers/scsi/Kconfig
@@ -620,6 +620,14 @@ config SCSI_FLASHPOINT
substantial, so users of MultiMaster Host Adapters may not
wish to include it.
+config VMWARE_PVSCSI
+ tristate "VMware PVSCSI driver support"
+ depends on PCI && SCSI && X86
+ help
+ This driver supports VMware's para virtualized SCSI HBA.
+ To compile this driver as a module, choose M here: the
+ module will be called pvscsi.
+
config LIBFC
tristate "LibFC module"
select SCSI_FC_ATTRS
diff --git a/drivers/scsi/Makefile b/drivers/scsi/Makefile
index 25429ea..27fd013 100644
--- a/drivers/scsi/Makefile
+++ b/drivers/scsi/Makefile
@@ -130,6 +130,7 @@ obj-$(CONFIG_SCSI_MVSAS) += mvsas/
obj-$(CONFIG_PS3_ROM) += ps3rom.o
obj-$(CONFIG_SCSI_CXGB3_ISCSI) += libiscsi.o libiscsi_tcp.o cxgb3i/
obj-$(CONFIG_SCSI_BNX2_ISCSI) += libiscsi.o bnx2i/
+obj-$(CONFIG_VMWARE_PVSCSI) += pvscsi.o
obj-$(CONFIG_ARM) += arm/
diff --git a/drivers/scsi/pvscsi.c b/drivers/scsi/pvscsi.c
new file mode 100644
index 0000000..34e78de
--- /dev/null
+++ b/drivers/scsi/pvscsi.c
@@ -0,0 +1,1400 @@
+/*
+ * Linux driver for VMware's para-virtualized SCSI HBA.
+ *
+ * Copyright (C) 2008-2009, 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.
+ *
+ * Maintained by: Alok N Kataria <akataria@xxxxxxxxxx>
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/types.h>
+#include <linux/interrupt.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 "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 64
+
+#define pvscsi_dev(adapter) (&(adapter->host->shost_gendev))
+
+struct pvscsi_sg_list {
+ 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 pvscsi_adapter {
+ char *mmioBase;
+ unsigned int irq;
+ u8 rev;
+ bool use_msi;
+ bool use_msix;
+ bool use_msg;
+
+ spinlock_t hw_lock;
+
+ struct workqueue_struct *workqueue;
+ struct work_struct work;
+
+ PVSCSIRingReqDesc *req_ring;
+ unsigned req_pages;
+ unsigned req_depth;
+ dma_addr_t reqRingPA;
+
+ PVSCSIRingCmpDesc *cmp_ring;
+ unsigned cmp_pages;
+ dma_addr_t cmpRingPA;
+
+ PVSCSIRingMsgDesc *msg_ring;
+ unsigned msg_pages;
+ dma_addr_t msgRingPA;
+
+ 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 = PVSCSI_DEFAULT_NUM_PAGES_PER_RING;
+static int pvscsi_msg_ring_pages = PVSCSI_DEFAULT_NUM_PAGES_MSG_RING;
+static int pvscsi_cmd_per_lun = PVSCSI_DEFAULT_QUEUE_DEPTH;
+static int pvscsi_disable_msi;
+static int pvscsi_disable_msix;
+static int pvscsi_use_msg = 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) ")");
+
+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_MAX_REQ_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)");
+
+static const struct pci_device_id pvscsi_pci_tbl[] = {
+ { PCI_DEVICE(PCI_VENDOR_ID_VMWARE, PCI_DEVICE_ID_VMWARE_PVSCSI) },
+ { 0 }
+};
+
+MODULE_DEVICE_TABLE(pci, pvscsi_pci_tbl);
+
+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_entry(adapter->cmd_pool.next, 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;
+ 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.
+ */
+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;
+ unsigned i;
+
+ len /= sizeof(u32);
+ 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)
+{
+ 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))
+ 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), "Reseting 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)
+{
+ PVSCSICmdDescResetDevice cmd = { 0 };
+
+ dev_dbg(pvscsi_dev(adapter), "Reseting 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++) {
+ 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 void pvscsi_map_buffers(struct pvscsi_adapter *adapter,
+ struct pvscsi_ctx *ctx,
+ struct scsi_cmnd *cmd, PVSCSIRingReqDesc *e)
+{
+ unsigned count;
+ unsigned bufflen = scsi_bufflen(cmd);
+ struct scatterlist *sg;
+
+ e->dataLen = bufflen;
+ e->dataAddr = 0;
+ if (bufflen == 0)
+ return;
+
+ sg = scsi_sglist(cmd);
+ count = scsi_sg_count(cmd);
+ if (count != 0) {
+ int segs = pci_map_sg(adapter->dev, sg, count,
+ cmd->sc_data_direction);
+ if (segs > 1) {
+ pvscsi_create_sg(ctx, sg, segs);
+
+ e->flags |= PVSCSI_FLAG_CMD_WITH_SG_LIST;
+ 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 = pci_map_single(adapter->dev, sg, bufflen,
+ cmd->sc_data_direction);
+ e->dataAddr = ctx->dataPA;
+ }
+}
+
+static void pvscsi_unmap_buffers(const struct pvscsi_adapter *adapter,
+ const 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)
+ pci_unmap_sg(adapter->dev, scsi_sglist(cmd), count,
+ cmd->sc_data_direction);
+ else
+ pci_unmap_single(adapter->dev, ctx->dataPA, bufflen,
+ cmd->sc_data_direction);
+ }
+ if (cmd->sense_buffer)
+ pci_unmap_single(adapter->dev, ctx->sensePA,
+ SCSI_SENSE_BUFFERSIZE, PCI_DMA_FROMDEVICE);
+}
+
+static int __devinit pvscsi_allocate_rings(struct pvscsi_adapter *adapter)
+{
+ adapter->rings_state = pci_alloc_consistent(adapter->dev, PAGE_SIZE,
+ &adapter->ringStatePA);
+ 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 = pci_alloc_consistent(adapter->dev,
+ adapter->req_pages * PAGE_SIZE,
+ &adapter->reqRingPA);
+ if (!adapter->req_ring)
+ return -ENOMEM;
+
+ adapter->cmp_pages = min(PVSCSI_MAX_NUM_PAGES_CMP_RING,
+ pvscsi_ring_pages);
+ adapter->cmp_ring = pci_alloc_consistent(adapter->dev,
+ adapter->cmp_pages * PAGE_SIZE,
+ &adapter->cmpRingPA);
+ if (!adapter->cmp_ring)
+ return -ENOMEM;
+
+ BUG_ON(adapter->ringStatePA & ~PAGE_MASK);
+ BUG_ON(adapter->reqRingPA & ~PAGE_MASK);
+ BUG_ON(adapter->cmpRingPA & ~PAGE_MASK);
+
+ if (!adapter->use_msg)
+ return 0;
+
+ adapter->msg_pages = min(PVSCSI_MAX_NUM_PAGES_MSG_RING,
+ pvscsi_msg_ring_pages);
+ adapter->msg_ring = pci_alloc_consistent(adapter->dev,
+ adapter->msg_pages * PAGE_SIZE,
+ &adapter->msgRingPA);
+ if (!adapter->msg_ring)
+ return -ENOMEM;
+ BUG_ON(adapter->msgRingPA & ~PAGE_MASK);
+
+ return 0;
+}
+
+static void pvscsi_setup_all_rings(const struct pvscsi_adapter *adapter)
+{
+ 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) {
+ 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);
+ }
+}
+
+/*
+ * 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 PVSCSIRingCmpDesc *e)
+{
+ struct pvscsi_ctx *ctx;
+ struct scsi_cmnd *cmd;
+ u32 btstat = e->hostStatus;
+ u32 sdstat = e->scsiStatus;
+
+ ctx = pvscsi_get_context(adapter, e->context);
+ cmd = ctx->cmd;
+ pvscsi_unmap_buffers(adapter, ctx);
+ pvscsi_release_context(adapter, ctx);
+ cmd->result = 0;
+
+ if (sdstat != SAM_STAT_GOOD &&
+ (btstat == BTSTAT_SUCCESS ||
+ btstat == BTSTAT_LINKED_COMMAND_COMPLETED ||
+ btstat == BTSTAT_LINKED_COMMAND_COMPLETED_WITH_FLAG)) {
+ cmd->result = (DID_OK << 16) | sdstat;
+ if (sdstat == SAM_STAT_CHECK_CONDITION && cmd->sense_buffer)
+ cmd->result |= (DRIVER_SENSE << 24);
+ } else
+ switch (btstat) {
+ case BTSTAT_SUCCESS:
+ case BTSTAT_LINKED_COMMAND_COMPLETED:
+ case BTSTAT_LINKED_COMMAND_COMPLETED_WITH_FLAG:
+ /* If everything went fine, let's move on.. */
+ 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:
+ cmd->result = (DRIVER_INVALID << 24);
+ /* fall through */
+
+ 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_ABORT << 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);
+ }
+
+ scmd_printk(KERN_DEBUG, cmd,
+ "cmd=%p %x ctx=%p result=0x%x status=0x%x,%x\n",
+ cmd, cmd->cmnd[0], ctx, cmd->result, btstat, sdstat);
+
+ cmd->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)
+{
+ PVSCSIRingsState *s = adapter->rings_state;
+ PVSCSIRingCmpDesc *ring = adapter->cmp_ring;
+ u32 cmp_entries = s->cmpNumEntriesLog2;
+
+ while (s->cmpConsIdx != s->cmpProdIdx) {
+ 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)
+{
+ PVSCSIRingsState *s;
+ 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,
+ "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 = pci_map_single(adapter->dev, cmd->sense_buffer,
+ SCSI_SENSE_BUFFERSIZE,
+ PCI_DMA_FROMDEVICE);
+ 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 (sdev->tagged_supported &&
+ (cmd->tag == HEAD_OF_QUEUE_TAG ||
+ cmd->tag == ORDERED_QUEUE_TAG))
+ e->tag = cmd->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;
+
+ pvscsi_map_buffers(adapter, ctx, cmd, e);
+
+ e->context = pvscsi_map_context(adapter, ctx);
+
+ barrier();
+
+ s->reqProdIdx++;
+
+ return 0;
+}
+
+static int pvscsi_queue(struct scsi_cmnd *cmd, void (*done)(struct scsi_cmnd *))
+{
+ struct Scsi_Host *host = cmd->device->host;
+ struct pvscsi_adapter *adapter = shost_priv(host);
+ struct pvscsi_ctx *ctx;
+ unsigned long flags;
+
+ 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;
+ }
+
+ cmd->scsi_done = done;
+
+ scmd_printk(KERN_DEBUG, cmd,
+ "queued cmd %p, ctx %p, op=%x\n", cmd, ctx, cmd->cmnd[0]);
+
+ spin_unlock_irqrestore(&adapter->hw_lock, flags);
+
+ pvscsi_kick_io(adapter, cmd->cmnd[0]);
+
+ return 0;
+}
+
+static int pvscsi_abort(struct scsi_cmnd *cmd)
+{
+ struct pvscsi_adapter *adapter = shost_priv(cmd->device->host);
+ struct pvscsi_ctx *ctx;
+ unsigned long flags;
+
+ 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;
+ }
+
+ pvscsi_abort_cmd(adapter, ctx);
+
+ pvscsi_process_completion_ring(adapter);
+
+out:
+ spin_unlock_irqrestore(&adapter->hw_lock, flags);
+ return SUCCESS;
+}
+
+/*
+ * 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_release_context(adapter, ctx);
+ cmd->result = (DID_RESET << 16);
+ cmd->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 = 0;
+ 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[512];
+
+ 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 = "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,
+ .use_clustering = ENABLE_CLUSTERING,
+ .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 PVSCSIRingMsgDesc *e)
+{
+ PVSCSIRingsState *s = adapter->rings_state;
+ struct Scsi_Host *host = adapter->host;
+ struct scsi_device *sdev;
+
+ printk(KERN_INFO "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) {
+ PVSCSIMsgDescDevStatusChanged *desc;
+ desc = (PVSCSIMsgDescDevStatusChanged *)e;
+
+ printk(KERN_INFO "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 "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) {
+ PVSCSIMsgDescDevStatusChanged *desc;
+ desc = (PVSCSIMsgDescDevStatusChanged *)e;
+
+ printk(KERN_INFO "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 "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)
+{
+ PVSCSIRingsState *s = adapter->rings_state;
+
+ return s->msgProdIdx != s->msgConsIdx;
+}
+
+static void pvscsi_process_msg_ring(const struct pvscsi_adapter *adapter)
+{
+ PVSCSIRingsState *s = adapter->rings_state;
+ PVSCSIRingMsgDesc *ring = adapter->msg_ring;
+ u32 msg_entries = s->msgNumEntriesLog2;
+
+ while (pvscsi_msg_pending(adapter)) {
+ 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, "pvscsi_wq_%u", adapter->host->host_no);
+
+ adapter->workqueue = create_singlethread_workqueue(name);
+ if (!adapter->workqueue) {
+ printk(KERN_ERR "pvscsi: failed to create work queue\n");
+ return 0;
+ }
+ INIT_WORK(&adapter->work, pvscsi_msg_workqueue_handler);
+
+ return 1;
+}
+
+static irqreturn_t pvscsi_isr(int irq, void *devp)
+{
+ struct pvscsi_adapter *adapter = devp;
+ int handled;
+
+ if (adapter->use_msi || adapter->use_msix)
+ handled = true;
+ else {
+ u32 val = pvscsi_read_intr_status(adapter);
+ handled = (val & PVSCSI_INTR_ALL_SUPPORTED) != 0;
+ if (handled)
+ pvscsi_write_intr_status(devp, val);
+ }
+
+ if (handled) {
+ 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_RETVAL(handled);
+}
+
+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)
+ pci_free_consistent(adapter->dev, PAGE_SIZE, ctx->sgl,
+ ctx->sglPA);
+}
+
+static int pvscsi_setup_msix(const struct pvscsi_adapter *adapter, int *irq)
+{
+#ifdef CONFIG_PCI_MSI
+ struct msix_entry entry = { 0, PVSCSI_VECTOR_COMPLETION };
+ int ret;
+
+ ret = pci_enable_msix(adapter->dev, &entry, 1);
+ if (ret)
+ return ret;
+
+ *irq = entry.vector;
+
+ return 0;
+#else
+ return -1;
+#endif
+}
+
+static void pvscsi_shutdown_intr(struct pvscsi_adapter *adapter)
+{
+ if (adapter->irq) {
+ free_irq(adapter->irq, adapter);
+ adapter->irq = 0;
+ }
+#ifdef CONFIG_PCI_MSI
+ if (adapter->use_msi) {
+ pci_disable_msi(adapter->dev);
+ adapter->use_msi = 0;
+ }
+
+ if (adapter->use_msix) {
+ pci_disable_msix(adapter->dev);
+ adapter->use_msix = 0;
+ }
+#endif
+}
+
+static void pvscsi_release_resources(struct pvscsi_adapter *adapter)
+{
+ pvscsi_shutdown_intr(adapter);
+
+ if (adapter->workqueue)
+ destroy_workqueue(adapter->workqueue);
+
+ if (adapter->mmioBase)
+ iounmap(adapter->mmioBase);
+
+ pci_release_regions(adapter->dev);
+
+ if (adapter->cmd_map) {
+ pvscsi_free_sgls(adapter);
+ kfree(adapter->cmd_map);
+ }
+
+ if (adapter->rings_state)
+ pci_free_consistent(adapter->dev, PAGE_SIZE,
+ adapter->rings_state, adapter->ringStatePA);
+
+ if (adapter->req_ring)
+ pci_free_consistent(adapter->dev,
+ adapter->req_pages * PAGE_SIZE,
+ adapter->req_ring, adapter->reqRingPA);
+
+ if (adapter->cmp_ring)
+ pci_free_consistent(adapter->dev,
+ adapter->cmp_pages * PAGE_SIZE,
+ adapter->cmp_ring, adapter->cmpRingPA);
+
+ if (adapter->msg_ring)
+ pci_free_consistent(adapter->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 deeep 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 __devinit 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) > PAGE_SIZE);
+
+ for (i = 0; i < adapter->req_depth; ++i, ++ctx) {
+ ctx->sgl = pci_alloc_consistent(adapter->dev, PAGE_SIZE,
+ &ctx->sglPA);
+ BUG_ON(ctx->sglPA & ~PAGE_MASK);
+ if (!ctx->sgl) {
+ for (; i >= 0; --i, --ctx) {
+ pci_free_consistent(adapter->dev, PAGE_SIZE,
+ ctx->sgl, ctx->sglPA);
+ ctx->sgl = NULL;
+ ctx->sglPA = 0;
+ }
+ return -ENOMEM;
+ }
+ }
+
+ return 0;
+}
+
+static int __devinit pvscsi_probe(struct pci_dev *pdev,
+ const struct pci_device_id *id)
+{
+ struct pvscsi_adapter *adapter;
+ struct Scsi_Host *host;
+ unsigned long base, i;
+ int error;
+
+ error = -ENODEV;
+
+ if (pci_enable_device(pdev))
+ return error;
+
+ if (pci_set_dma_mask(pdev, DMA_BIT_MASK(64)) == 0 &&
+ pci_set_consistent_dma_mask(pdev, DMA_BIT_MASK(64)) == 0) {
+ printk(KERN_INFO "pvscsi: using 64bit dma\n");
+ } else if (pci_set_dma_mask(pdev, DMA_BIT_MASK(32)) == 0 &&
+ pci_set_consistent_dma_mask(pdev, DMA_BIT_MASK(32)) == 0) {
+ printk(KERN_INFO "pvscsi: using 32bit dma\n");
+ } else {
+ printk(KERN_ERR "pvscsi: failed to set DMA mask\n");
+ goto out_disable_device;
+ }
+
+ 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 "pvscsi: failed to allocate host\n");
+ goto out_disable_device;
+ }
+
+ adapter = shost_priv(host);
+ memset(adapter, 0, sizeof *adapter);
+ adapter->dev = pdev;
+ adapter->host = host;
+
+ spin_lock_init(&adapter->hw_lock);
+
+ host->max_channel = 0;
+ host->max_id = 16;
+ host->max_lun = 1;
+
+ pci_read_config_byte(pdev, PCI_CLASS_REVISION, &adapter->rev);
+
+ if (pci_request_regions(pdev, "pvscsi")) {
+ printk(KERN_ERR "pvscsi: pci memory selection failed\n");
+ goto out_free_host;
+ }
+
+ base = 0;
+ 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_NUM_PAGES * PAGE_SIZE)
+ continue;
+
+ base = pci_resource_start(pdev, i);
+ break;
+ }
+
+ if (base == 0) {
+ printk(KERN_ERR "pvscsi: adapter has no suitable MMIO region\n");
+ goto out_release_resources;
+ }
+
+ adapter->mmioBase = ioremap(base, PVSCSI_MEM_SPACE_SIZE);
+ if (!adapter->mmioBase) {
+ printk(KERN_ERR "pvscsi: can't ioremap 0x%lx\n", base);
+ goto out_release_resources;
+ }
+
+ pci_set_master(pdev);
+ 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 "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 = kmalloc(adapter->req_depth *
+ sizeof(struct pvscsi_ctx), GFP_KERNEL);
+ if (!adapter->cmd_map) {
+ printk(KERN_ERR "pvscsi: failed to allocate memory.\n");
+ error = -ENOMEM;
+ goto out_reset_adapter;
+ }
+ memset(adapter->cmd_map, 0,
+ adapter->req_depth * sizeof(struct pvscsi_ctx));
+
+ 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 "pvscsi: unable to allocate s/g table\n");
+ goto out_reset_adapter;
+ }
+
+ if (!pvscsi_disable_msix &&
+ pvscsi_setup_msix(adapter, &adapter->irq) == 0) {
+ printk(KERN_INFO "pvscsi: using MSI-X\n");
+ adapter->use_msix = 1;
+ } else if (!pvscsi_disable_msi && pci_enable_msi(pdev) == 0) {
+ printk(KERN_INFO "pvscsi: using MSI\n");
+ adapter->use_msi = 1;
+ adapter->irq = pdev->irq;
+ } else {
+ printk(KERN_INFO "pvscsi: using INTx\n");
+ adapter->irq = pdev->irq;
+ }
+
+ error = request_irq(adapter->irq, pvscsi_isr, IRQF_SHARED,
+ "pvscsi", adapter);
+ if (error) {
+ printk(KERN_ERR "pvscsi: unable to request IRQ: %d\n", error);
+ adapter->irq = 0;
+ goto out_reset_adapter;
+ }
+
+ error = scsi_add_host(host, &pdev->dev);
+ if (error) {
+ printk(KERN_ERR "pvscsi: scsi_add_host failed: %d\n", error);
+ goto out_reset_adapter;
+ }
+
+ printk(KERN_INFO "VMware PVSCSI rev %d on bus:%u slot:%u func:%u host #%u\n",
+ adapter->rev, pdev->bus->number, PCI_SLOT(pdev->devfn),
+ PCI_FUNC(pdev->devfn), host->host_no);
+
+ pvscsi_unmask_intr(adapter);
+
+ scsi_scan_host(host);
+
+ return 0;
+
+out_reset_adapter:
+ ll_adapter_reset(adapter);
+out_release_resources:
+ pvscsi_release_resources(adapter);
+out_free_host:
+ scsi_host_put(host);
+out_disable_device:
+ pci_set_drvdata(pdev, NULL);
+ pci_disable_device(pdev);
+
+ return error;
+}
+
+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_set_drvdata(pdev, NULL);
+ pci_disable_device(pdev);
+}
+
+static struct pci_driver pvscsi_pci_driver = {
+ .name = "pvscsi",
+ .id_table = pvscsi_pci_tbl,
+ .probe = pvscsi_probe,
+ .remove = __devexit_p(pvscsi_remove),
+ .shutdown = pvscsi_shutdown,
+};
+
+static int __init pvscsi_init(void)
+{
+ printk(KERN_DEBUG "%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);
diff --git a/drivers/scsi/pvscsi.h b/drivers/scsi/pvscsi.h
new file mode 100644
index 0000000..96bb655
--- /dev/null
+++ b/drivers/scsi/pvscsi.h
@@ -0,0 +1,395 @@
+/*
+ * VMware PVSCSI header file
+ *
+ * Copyright (C) 2008-2009, 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.
+ *
+ * Maintained by: Alok N Kataria <akataria@xxxxxxxxxx>
+ *
+ */
+
+#ifndef _PVSCSI_H_
+#define _PVSCSI_H_
+
+#include <linux/types.h>
+
+#define PVSCSI_DRIVER_VERSION_STRING "1.0.0.0"
+
+#define PVSCSI_MAX_NUM_SG_ENTRIES_PER_SEGMENT 128
+
+#define MASK(n) ((1 << (n)) - 1) /* make an n-bit mask */
+
+#define PCI_VENDOR_ID_VMWARE 0x15AD
+#define PCI_DEVICE_ID_VMWARE_PVSCSI 0x07C0
+
+/*
+ * host adapter status/error codes
+ */
+typedef enum {
+ BTSTAT_SUCCESS = 0x00, /* CCB complete normally with no errors */
+ BTSTAT_LINKED_COMMAND_COMPLETED = 0x0a,
+ BTSTAT_LINKED_COMMAND_COMPLETED_WITH_FLAG = 0x0b,
+ BTSTAT_DATA_UNDERRUN = 0x0c,
+ BTSTAT_SELTIMEO = 0x11, /* SCSI selection timeout */
+ BTSTAT_DATARUN = 0x12, /* data overrun/underrun */
+ BTSTAT_BUSFREE = 0x13, /* unexpected bus free */
+ BTSTAT_INVPHASE = 0x14, /* invalid bus phase or sequence requested by target */
+ BTSTAT_LUNMISMATCH = 0x17, /* linked CCB has different LUN from first CCB */
+ BTSTAT_SENSFAILED = 0x1b, /* auto request sense failed */
+ BTSTAT_TAGREJECT = 0x1c, /* SCSI II tagged queueing message rejected by target */
+ BTSTAT_BADMSG = 0x1d, /* unsupported message received by the host adapter */
+ BTSTAT_HAHARDWARE = 0x20, /* host adapter hardware failed */
+ BTSTAT_NORESPONSE = 0x21, /* target did not respond to SCSI ATN, sent a SCSI RST */
+ BTSTAT_SENTRST = 0x22, /* host adapter asserted a SCSI RST */
+ BTSTAT_RECVRST = 0x23, /* other SCSI devices asserted a SCSI RST */
+ BTSTAT_DISCONNECT = 0x24, /* target device reconnected improperly (w/o tag) */
+ BTSTAT_BUSRESET = 0x25, /* host adapter issued BUS device reset */
+ BTSTAT_ABORTQUEUE = 0x26, /* abort queue generated */
+ BTSTAT_HASOFTWARE = 0x27, /* host adapter software error */
+ BTSTAT_HATIMEOUT = 0x30, /* host adapter hardware timeout error */
+ BTSTAT_SCSIPARITY = 0x34, /* SCSI parity error detected */
+} HostBusAdapterStatus;
+
+/*
+ * Register offsets.
+ *
+ * These registers are accessible both via i/o space and mm i/o.
+ */
+
+enum PVSCSIRegOffset {
+ PVSCSI_REG_OFFSET_COMMAND = 0x0,
+ PVSCSI_REG_OFFSET_COMMAND_DATA = 0x4,
+ PVSCSI_REG_OFFSET_COMMAND_STATUS = 0x8,
+ PVSCSI_REG_OFFSET_LAST_STS_0 = 0x100,
+ PVSCSI_REG_OFFSET_LAST_STS_1 = 0x104,
+ PVSCSI_REG_OFFSET_LAST_STS_2 = 0x108,
+ PVSCSI_REG_OFFSET_LAST_STS_3 = 0x10c,
+ PVSCSI_REG_OFFSET_INTR_STATUS = 0x100c,
+ PVSCSI_REG_OFFSET_INTR_MASK = 0x2010,
+ PVSCSI_REG_OFFSET_KICK_NON_RW_IO = 0x3014,
+ PVSCSI_REG_OFFSET_DEBUG = 0x3018,
+ PVSCSI_REG_OFFSET_KICK_RW_IO = 0x4018,
+};
+
+/*
+ * Virtual h/w commands.
+ */
+
+enum PVSCSICommands {
+ PVSCSI_CMD_FIRST = 0, /* has to be first */
+
+ PVSCSI_CMD_ADAPTER_RESET = 1,
+ PVSCSI_CMD_ISSUE_SCSI = 2,
+ PVSCSI_CMD_SETUP_RINGS = 3,
+ PVSCSI_CMD_RESET_BUS = 4,
+ PVSCSI_CMD_RESET_DEVICE = 5,
+ PVSCSI_CMD_ABORT_CMD = 6,
+ PVSCSI_CMD_CONFIG = 7,
+ PVSCSI_CMD_SETUP_MSG_RING = 8,
+ PVSCSI_CMD_DEVICE_UNPLUG = 9,
+
+ PVSCSI_CMD_LAST = 10 /* has to be last */
+};
+
+/*
+ * Command descriptor for PVSCSI_CMD_RESET_DEVICE --
+ */
+
+typedef struct PVSCSICmdDescResetDevice {
+ u32 target;
+ u8 lun[8];
+} __packed PVSCSICmdDescResetDevice;
+
+/*
+ * Command descriptor for PVSCSI_CMD_ABORT_CMD --
+ *
+ * - currently does not support specifying the LUN.
+ * - _pad should be 0.
+ */
+
+typedef struct PVSCSICmdDescAbortCmd {
+ u64 context;
+ u32 target;
+ u32 _pad;
+} __packed PVSCSICmdDescAbortCmd;
+
+/*
+ * Command descriptor for PVSCSI_CMD_SETUP_RINGS --
+ *
+ * Notes:
+ * - reqRingNumPages and cmpRingNumPages need to be power of two.
+ * - reqRingNumPages and cmpRingNumPages need to be different from 0,
+ * - reqRingNumPages and cmpRingNumPages need to be inferior to
+ * PVSCSI_SETUP_RINGS_MAX_NUM_PAGES.
+ */
+
+#define PVSCSI_SETUP_RINGS_MAX_NUM_PAGES 32
+typedef struct PVSCSICmdDescSetupRings {
+ u32 reqRingNumPages;
+ u32 cmpRingNumPages;
+ u64 ringsStatePPN;
+ u64 reqRingPPNs[PVSCSI_SETUP_RINGS_MAX_NUM_PAGES];
+ u64 cmpRingPPNs[PVSCSI_SETUP_RINGS_MAX_NUM_PAGES];
+} __packed PVSCSICmdDescSetupRings;
+
+/*
+ * Command descriptor for PVSCSI_CMD_SETUP_MSG_RING --
+ *
+ * Notes:
+ * - this command was not supported in the initial revision of the h/w
+ * interface. Before using it, you need to check that it is supported by
+ * writing PVSCSI_CMD_SETUP_MSG_RING to the 'command' register, then
+ * immediately after read the 'command status' register:
+ * * a value of -1 means that the cmd is NOT supported,
+ * * a value != -1 means that the cmd IS supported.
+ * If it's supported the 'command status' register should return:
+ * sizeof(PVSCSICmdDescSetupMsgRing) / sizeof(u32).
+ * - this command should be issued _after_ the usual SETUP_RINGS so that the
+ * RingsState page is already setup. If not, the command is a nop.
+ * - numPages needs to be a power of two,
+ * - numPages needs to be different from 0,
+ * - _pad should be zero.
+ */
+
+#define PVSCSI_SETUP_MSG_RING_MAX_NUM_PAGES 16
+
+typedef struct PVSCSICmdDescSetupMsgRing {
+ u32 numPages;
+ u32 _pad;
+ u64 ringPPNs[PVSCSI_SETUP_MSG_RING_MAX_NUM_PAGES];
+} __packed PVSCSICmdDescSetupMsgRing;
+
+enum PVSCSIMsgType {
+ PVSCSI_MSG_DEV_ADDED = 0,
+ PVSCSI_MSG_DEV_REMOVED = 1,
+ PVSCSI_MSG_LAST = 2,
+};
+
+/*
+ * Msg descriptor.
+ *
+ * sizeof(struct PVSCSIRingMsgDesc) == 128.
+ *
+ * - type is of type enum PVSCSIMsgType.
+ * - the content of args depend on the type of event being delivered.
+ */
+
+typedef struct PVSCSIRingMsgDesc {
+ u32 type;
+ u32 args[31];
+} __packed PVSCSIRingMsgDesc;
+
+typedef struct PVSCSIMsgDescDevStatusChanged {
+ u32 type; /* PVSCSI_MSG_DEV _ADDED / _REMOVED */
+ u32 bus;
+ u32 target;
+ u8 lun[8];
+ u32 pad[27];
+} __packed PVSCSIMsgDescDevStatusChanged;
+
+/*
+ * Rings state.
+ *
+ * - the fields:
+ * . msgProdIdx,
+ * . msgConsIdx,
+ * . msgNumEntriesLog2,
+ * .. are only used once the SETUP_MSG_RING cmd has been issued.
+ * - '_pad' helps to ensure that the msg related fields are on their own
+ * cache-line.
+ */
+
+typedef struct PVSCSIRingsState {
+ u32 reqProdIdx;
+ u32 reqConsIdx;
+ u32 reqNumEntriesLog2;
+
+ u32 cmpProdIdx;
+ u32 cmpConsIdx;
+ u32 cmpNumEntriesLog2;
+
+ u8 _pad[104];
+
+ u32 msgProdIdx;
+ u32 msgConsIdx;
+ u32 msgNumEntriesLog2;
+} __packed PVSCSIRingsState;
+
+/*
+ * Request descriptor.
+ *
+ * sizeof(RingReqDesc) = 128
+ *
+ * - context: is a unique identifier of a command. It could normally be any
+ * 64bit value, however we currently store it in the serialNumber variable
+ * of struct SCSI_Command, so we have the following restrictions due to the
+ * way this field is handled in the vmkernel storage stack:
+ * * this value can't be 0,
+ * * the upper 32bit need to be 0 since serialNumber is as a u32.
+ * Currently tracked as PR 292060.
+ * - dataLen: contains the total number of bytes that need to be transferred.
+ * - dataAddr:
+ * * if PVSCSI_FLAG_CMD_WITH_SG_LIST is set: dataAddr is the PA of the first
+ * s/g table segment, each s/g segment is entirely contained on a single
+ * page of physical memory,
+ * * if PVSCSI_FLAG_CMD_WITH_SG_LIST is NOT set, then dataAddr is the PA of
+ * the buffer used for the DMA transfer,
+ * - flags:
+ * * PVSCSI_FLAG_CMD_WITH_SG_LIST: see dataAddr above,
+ * * PVSCSI_FLAG_CMD_DIR_NONE: no DMA involved,
+ * * PVSCSI_FLAG_CMD_DIR_TOHOST: transfer from device to main memory,
+ * * PVSCSI_FLAG_CMD_DIR_TODEVICE: transfer from main memory to device,
+ * * PVSCSI_FLAG_CMD_OUT_OF_BAND_CDB: reserved to handle CDBs larger than
+ * 16bytes. To be specified.
+ * - vcpuHint: vcpuId of the processor that will be most likely waiting for the
+ * completion of the i/o. For guest OSes that use lowest priority message
+ * delivery mode (such as windows), we use this "hint" to deliver the
+ * completion action to the proper vcpu. For now, we can use the vcpuId of
+ * the processor that initiated the i/o as a likely candidate for the vcpu
+ * that will be waiting for the completion..
+ * - bus should be 0: we currently only support bus 0 for now.
+ * - unused should be zero'd.
+ */
+
+#define PVSCSI_FLAG_CMD_WITH_SG_LIST (1 << 0)
+#define PVSCSI_FLAG_CMD_OUT_OF_BAND_CDB (1 << 1)
+#define PVSCSI_FLAG_CMD_DIR_NONE (1 << 2)
+#define PVSCSI_FLAG_CMD_DIR_TOHOST (1 << 3)
+#define PVSCSI_FLAG_CMD_DIR_TODEVICE (1 << 4)
+
+typedef struct PVSCSIRingReqDesc {
+ u64 context;
+ u64 dataAddr;
+ u64 dataLen;
+ u64 senseAddr;
+ u32 senseLen;
+ u32 flags;
+ u8 cdb[16];
+ u8 cdbLen;
+ u8 lun[8];
+ u8 tag;
+ u8 bus;
+ u8 target;
+ u8 vcpuHint;
+ u8 unused[59];
+} __packed PVSCSIRingReqDesc;
+
+/*
+ * Scatter-gather list management.
+ *
+ * As described above, when PVSCSI_FLAG_CMD_WITH_SG_LIST is set in the
+ * RingReqDesc.flags, then RingReqDesc.dataAddr is the PA of the first s/g
+ * table segment.
+ *
+ * - each segment of the s/g table contain a succession of struct
+ * PVSCSISGElement.
+ * - each segment is entirely contained on a single physical page of memory.
+ * - a "chain" s/g element has the flag PVSCSI_SGE_FLAG_CHAIN_ELEMENT set in
+ * PVSCSISGElement.flags and in this case:
+ * * addr is the PA of the next s/g segment,
+ * * length is undefined, assumed to be 0.
+ */
+
+typedef struct PVSCSISGElement {
+ u64 addr;
+ u32 length;
+ u32 flags;
+} __packed PVSCSISGElement;
+
+/*
+ * Completion descriptor.
+ *
+ * sizeof(RingCmpDesc) = 32
+ *
+ * - context: identifier of the command. The same thing that was specified
+ * under "context" as part of struct RingReqDesc at initiation time,
+ * - dataLen: number of bytes transferred for the actual i/o operation,
+ * - senseLen: number of bytes written into the sense buffer,
+ * - hostStatus: adapter status,
+ * - scsiStatus: device status,
+ * - _pad should be zero.
+ */
+
+typedef struct PVSCSIRingCmpDesc {
+ u64 context;
+ u64 dataLen;
+ u32 senseLen;
+ u16 hostStatus;
+ u16 scsiStatus;
+ u32 _pad[2];
+} __packed PVSCSIRingCmpDesc;
+
+/*
+ * Interrupt status / IRQ bits.
+ */
+
+#define PVSCSI_INTR_CMPL_0 (1 << 0)
+#define PVSCSI_INTR_CMPL_1 (1 << 1)
+#define PVSCSI_INTR_CMPL_MASK MASK(2)
+
+#define PVSCSI_INTR_MSG_0 (1 << 2)
+#define PVSCSI_INTR_MSG_1 (1 << 3)
+#define PVSCSI_INTR_MSG_MASK (MASK(2) << 2)
+
+#define PVSCSI_INTR_ALL_SUPPORTED MASK(4)
+
+/*
+ * Number of MSI-X vectors supported.
+ */
+#define PVSCSI_MAX_INTRS 24
+
+/*
+ * Enumeration of supported MSI-X vectors
+ */
+#define PVSCSI_VECTOR_COMPLETION 0
+
+/*
+ * Misc constants for the rings.
+ */
+
+#define PVSCSI_MAX_NUM_PAGES_REQ_RING PVSCSI_SETUP_RINGS_MAX_NUM_PAGES
+#define PVSCSI_MAX_NUM_PAGES_CMP_RING PVSCSI_SETUP_RINGS_MAX_NUM_PAGES
+#define PVSCSI_MAX_NUM_PAGES_MSG_RING PVSCSI_SETUP_MSG_RING_MAX_NUM_PAGES
+
+#define PVSCSI_MAX_NUM_REQ_ENTRIES_PER_PAGE \
+ (PAGE_SIZE / sizeof(PVSCSIRingReqDesc))
+
+#define PVSCSI_MAX_REQ_QUEUE_DEPTH \
+ (PVSCSI_MAX_NUM_PAGES_REQ_RING * PVSCSI_MAX_NUM_REQ_ENTRIES_PER_PAGE)
+
+#define PVSCSI_MEM_SPACE_COMMAND_NUM_PAGES 1
+#define PVSCSI_MEM_SPACE_INTR_STATUS_NUM_PAGES 1
+#define PVSCSI_MEM_SPACE_MISC_NUM_PAGES 2
+#define PVSCSI_MEM_SPACE_KICK_IO_NUM_PAGES 2
+#define PVSCSI_MEM_SPACE_MSIX_NUM_PAGES 2
+
+#define PVSCSI_MEM_SPACE_COMMAND_PAGE 0
+#define PVSCSI_MEM_SPACE_INTR_STATUS_PAGE 1
+#define PVSCSI_MEM_SPACE_MISC_PAGE 2
+#define PVSCSI_MEM_SPACE_KICK_IO_PAGE 4
+#define PVSCSI_MEM_SPACE_MSIX_TABLE_PAGE 6
+#define PVSCSI_MEM_SPACE_MSIX_PBA_PAGE 7
+
+#define PVSCSI_MEM_SPACE_NUM_PAGES \
+ (PVSCSI_MEM_SPACE_COMMAND_NUM_PAGES + \
+ PVSCSI_MEM_SPACE_INTR_STATUS_NUM_PAGES + \
+ PVSCSI_MEM_SPACE_MISC_NUM_PAGES + \
+ PVSCSI_MEM_SPACE_KICK_IO_NUM_PAGES + \
+ PVSCSI_MEM_SPACE_MSIX_NUM_PAGES)
+
+#define PVSCSI_MEM_SPACE_SIZE (PVSCSI_MEM_SPACE_NUM_PAGES * PAGE_SIZE)
+
+#endif /* _PVSCSI_H_ */
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