diff options
Diffstat (limited to 'drivers/staging/hv/storvsc_drv.c')
-rw-r--r-- | drivers/staging/hv/storvsc_drv.c | 1208 |
1 files changed, 1208 insertions, 0 deletions
diff --git a/drivers/staging/hv/storvsc_drv.c b/drivers/staging/hv/storvsc_drv.c new file mode 100644 index 000000000000..d49dc21d4cb4 --- /dev/null +++ b/drivers/staging/hv/storvsc_drv.c @@ -0,0 +1,1208 @@ +/* + * Copyright (c) 2009, Microsoft Corporation. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions of the GNU General Public License, + * version 2, as published by the Free Software Foundation. + * + * This program is distributed in the hope it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. 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., 59 Temple + * Place - Suite 330, Boston, MA 02111-1307 USA. + * + * Authors: + * Haiyang Zhang <haiyangz@microsoft.com> + * Hank Janssen <hjanssen@microsoft.com> + */ +#include <linux/init.h> +#include <linux/module.h> +#include <linux/device.h> +#include <linux/blkdev.h> +#include <scsi/scsi.h> +#include <scsi/scsi_cmnd.h> +#include <scsi/scsi_host.h> +#include <scsi/scsi_device.h> +#include <scsi/scsi_tcq.h> +#include <scsi/scsi_eh.h> +#include <scsi/scsi_devinfo.h> +#include <scsi/scsi_dbg.h> +#include "osd.h" +#include "logging.h" +#include "vmbus.h" +#include "StorVscApi.h" + + +struct host_device_context { + /* must be 1st field + * FIXME this is a bug */ + struct work_struct host_rescan_work; + + /* point back to our device context */ + struct device_context *device_ctx; + struct kmem_cache *request_pool; + unsigned int port; + unsigned char path; + unsigned char target; +}; + +struct storvsc_cmd_request { + struct list_head entry; + struct scsi_cmnd *cmd; + + unsigned int bounce_sgl_count; + struct scatterlist *bounce_sgl; + + struct hv_storvsc_request request; + /* !!!DO NOT ADD ANYTHING BELOW HERE!!! */ + /* The extension buffer falls right here and is pointed to by + * request.Extension; + * Which sounds like a very bad design... */ +}; + +struct storvsc_driver_context { + /* !! These must be the first 2 fields !! */ + /* FIXME this is a bug... */ + struct driver_context drv_ctx; + struct storvsc_driver_object drv_obj; +}; + +/* Static decl */ +static int storvsc_probe(struct device *dev); +static int storvsc_queuecommand(struct scsi_cmnd *scmnd, + void (*done)(struct scsi_cmnd *)); +static int storvsc_device_alloc(struct scsi_device *); +static int storvsc_device_configure(struct scsi_device *); +static int storvsc_host_reset_handler(struct scsi_cmnd *scmnd); +static void storvsc_host_rescan_callback(struct work_struct *work); +static void storvsc_host_rescan(struct hv_device *device_obj); +static int storvsc_remove(struct device *dev); + +static struct scatterlist *create_bounce_buffer(struct scatterlist *sgl, + unsigned int sg_count, + unsigned int len); +static void destroy_bounce_buffer(struct scatterlist *sgl, + unsigned int sg_count); +static int do_bounce_buffer(struct scatterlist *sgl, unsigned int sg_count); +static unsigned int copy_from_bounce_buffer(struct scatterlist *orig_sgl, + struct scatterlist *bounce_sgl, + unsigned int orig_sgl_count); +static unsigned int copy_to_bounce_buffer(struct scatterlist *orig_sgl, + struct scatterlist *bounce_sgl, + unsigned int orig_sgl_count); + +static int storvsc_report_luns(struct scsi_device *sdev, unsigned int luns[], + unsigned int *lun_count); +static int storvsc_get_chs(struct scsi_device *sdev, struct block_device *bdev, + sector_t capacity, int *info); + + +static int storvsc_ringbuffer_size = STORVSC_RING_BUFFER_SIZE; + +/* The one and only one */ +static struct storvsc_driver_context g_storvsc_drv; + +/* Scsi driver */ +static struct scsi_host_template scsi_driver = { + .module = THIS_MODULE, + .name = "storvsc_host_t", + .bios_param = storvsc_get_chs, + .queuecommand = storvsc_queuecommand, + .eh_host_reset_handler = storvsc_host_reset_handler, + .slave_alloc = storvsc_device_alloc, + .slave_configure = storvsc_device_configure, + .cmd_per_lun = 1, + /* 64 max_queue * 1 target */ + .can_queue = STORVSC_MAX_IO_REQUESTS*STORVSC_MAX_TARGETS, + .this_id = -1, + /* no use setting to 0 since ll_blk_rw reset it to 1 */ + /* currently 32 */ + .sg_tablesize = MAX_MULTIPAGE_BUFFER_COUNT, + /* + * ENABLE_CLUSTERING allows mutiple physically contig bio_vecs to merge + * into 1 sg element. If set, we must limit the max_segment_size to + * PAGE_SIZE, otherwise we may get 1 sg element that represents + * multiple + */ + /* physically contig pfns (ie sg[x].length > PAGE_SIZE). */ + .use_clustering = ENABLE_CLUSTERING, + /* Make sure we dont get a sg segment crosses a page boundary */ + .dma_boundary = PAGE_SIZE-1, +}; + + +/** + * storvsc_drv_init - StorVsc driver initialization. + */ +static int storvsc_drv_init(int (*drv_init)(struct hv_driver *drv)) +{ + int ret; + struct storvsc_driver_object *storvsc_drv_obj = &g_storvsc_drv.drv_obj; + struct driver_context *drv_ctx = &g_storvsc_drv.drv_ctx; + + DPRINT_ENTER(STORVSC_DRV); + + vmbus_get_interface(&storvsc_drv_obj->Base.VmbusChannelInterface); + + storvsc_drv_obj->RingBufferSize = storvsc_ringbuffer_size; + storvsc_drv_obj->OnHostRescan = storvsc_host_rescan; + + /* Callback to client driver to complete the initialization */ + drv_init(&storvsc_drv_obj->Base); + + DPRINT_INFO(STORVSC_DRV, + "request extension size %u, max outstanding reqs %u", + storvsc_drv_obj->RequestExtSize, + storvsc_drv_obj->MaxOutstandingRequestsPerChannel); + + if (storvsc_drv_obj->MaxOutstandingRequestsPerChannel < + STORVSC_MAX_IO_REQUESTS) { + DPRINT_ERR(STORVSC_DRV, + "The number of outstanding io requests (%d) " + "is larger than that supported (%d) internally.", + STORVSC_MAX_IO_REQUESTS, + storvsc_drv_obj->MaxOutstandingRequestsPerChannel); + return -1; + } + + drv_ctx->driver.name = storvsc_drv_obj->Base.name; + memcpy(&drv_ctx->class_id, &storvsc_drv_obj->Base.deviceType, + sizeof(struct hv_guid)); + + drv_ctx->probe = storvsc_probe; + drv_ctx->remove = storvsc_remove; + + /* The driver belongs to vmbus */ + ret = vmbus_child_driver_register(drv_ctx); + + DPRINT_EXIT(STORVSC_DRV); + + return ret; +} + +static int storvsc_drv_exit_cb(struct device *dev, void *data) +{ + struct device **curr = (struct device **)data; + *curr = dev; + return 1; /* stop iterating */ +} + +static void storvsc_drv_exit(void) +{ + struct storvsc_driver_object *storvsc_drv_obj = &g_storvsc_drv.drv_obj; + struct driver_context *drv_ctx = &g_storvsc_drv.drv_ctx; + struct device *current_dev = NULL; + int ret; + + DPRINT_ENTER(STORVSC_DRV); + + while (1) { + current_dev = NULL; + + /* Get the device */ + ret = driver_for_each_device(&drv_ctx->driver, NULL, + (void *) ¤t_dev, + storvsc_drv_exit_cb); + + if (ret) + DPRINT_WARN(STORVSC_DRV, + "driver_for_each_device returned %d", ret); + + if (current_dev == NULL) + break; + + /* Initiate removal from the top-down */ + device_unregister(current_dev); + } + + if (storvsc_drv_obj->Base.OnCleanup) + storvsc_drv_obj->Base.OnCleanup(&storvsc_drv_obj->Base); + + vmbus_child_driver_unregister(drv_ctx); + + DPRINT_EXIT(STORVSC_DRV); + + return; +} + +/** + * storvsc_probe - Add a new device for this driver + */ +static int storvsc_probe(struct device *device) +{ + int ret; + struct driver_context *driver_ctx = + driver_to_driver_context(device->driver); + struct storvsc_driver_context *storvsc_drv_ctx = + (struct storvsc_driver_context *)driver_ctx; + struct storvsc_driver_object *storvsc_drv_obj = + &storvsc_drv_ctx->drv_obj; + struct device_context *device_ctx = device_to_device_context(device); + struct hv_device *device_obj = &device_ctx->device_obj; + struct Scsi_Host *host; + struct host_device_context *host_device_ctx; + struct storvsc_device_info device_info; + + DPRINT_ENTER(STORVSC_DRV); + + if (!storvsc_drv_obj->Base.OnDeviceAdd) + return -1; + + host = scsi_host_alloc(&scsi_driver, + sizeof(struct host_device_context)); + if (!host) { + DPRINT_ERR(STORVSC_DRV, "unable to allocate scsi host object"); + return -ENOMEM; + } + + dev_set_drvdata(device, host); + + host_device_ctx = (struct host_device_context *)host->hostdata; + memset(host_device_ctx, 0, sizeof(struct host_device_context)); + + host_device_ctx->port = host->host_no; + host_device_ctx->device_ctx = device_ctx; + + INIT_WORK(&host_device_ctx->host_rescan_work, + storvsc_host_rescan_callback); + + host_device_ctx->request_pool = + kmem_cache_create(dev_name(&device_ctx->device), + sizeof(struct storvsc_cmd_request) + + storvsc_drv_obj->RequestExtSize, 0, + SLAB_HWCACHE_ALIGN, NULL); + + if (!host_device_ctx->request_pool) { + scsi_host_put(host); + DPRINT_EXIT(STORVSC_DRV); + + return -ENOMEM; + } + + device_info.PortNumber = host->host_no; + /* Call to the vsc driver to add the device */ + ret = storvsc_drv_obj->Base.OnDeviceAdd(device_obj, + (void *)&device_info); + if (ret != 0) { + DPRINT_ERR(STORVSC_DRV, "unable to add scsi vsc device"); + kmem_cache_destroy(host_device_ctx->request_pool); + scsi_host_put(host); + DPRINT_EXIT(STORVSC_DRV); + + return -1; + } + + /* host_device_ctx->port = device_info.PortNumber; */ + host_device_ctx->path = device_info.PathId; + host_device_ctx->target = device_info.TargetId; + + /* max # of devices per target */ + host->max_lun = STORVSC_MAX_LUNS_PER_TARGET; + /* max # of targets per channel */ + host->max_id = STORVSC_MAX_TARGETS; + /* max # of channels */ + host->max_channel = STORVSC_MAX_CHANNELS - 1; + + /* Register the HBA and start the scsi bus scan */ + ret = scsi_add_host(host, device); + if (ret != 0) { + DPRINT_ERR(STORVSC_DRV, "unable to add scsi host device"); + + storvsc_drv_obj->Base.OnDeviceRemove(device_obj); + + kmem_cache_destroy(host_device_ctx->request_pool); + scsi_host_put(host); + DPRINT_EXIT(STORVSC_DRV); + + return -1; + } + + scsi_scan_host(host); + + DPRINT_EXIT(STORVSC_DRV); + + return ret; +} + +/** + * storvsc_remove - Callback when our device is removed + */ +static int storvsc_remove(struct device *device) +{ + int ret; + struct driver_context *driver_ctx = + driver_to_driver_context(device->driver); + struct storvsc_driver_context *storvsc_drv_ctx = + (struct storvsc_driver_context *)driver_ctx; + struct storvsc_driver_object *storvsc_drv_obj = + &storvsc_drv_ctx->drv_obj; + struct device_context *device_ctx = device_to_device_context(device); + struct hv_device *device_obj = &device_ctx->device_obj; + struct Scsi_Host *host = dev_get_drvdata(device); + struct host_device_context *host_device_ctx = + (struct host_device_context *)host->hostdata; + + + DPRINT_ENTER(STORVSC_DRV); + + if (!storvsc_drv_obj->Base.OnDeviceRemove) { + DPRINT_EXIT(STORVSC_DRV); + return -1; + } + + /* + * Call to the vsc driver to let it know that the device is being + * removed + */ + ret = storvsc_drv_obj->Base.OnDeviceRemove(device_obj); + if (ret != 0) { + /* TODO: */ + DPRINT_ERR(STORVSC, "unable to remove vsc device (ret %d)", + ret); + } + + if (host_device_ctx->request_pool) { + kmem_cache_destroy(host_device_ctx->request_pool); + host_device_ctx->request_pool = NULL; + } + + DPRINT_INFO(STORVSC, "removing host adapter (%p)...", host); + scsi_remove_host(host); + + DPRINT_INFO(STORVSC, "releasing host adapter (%p)...", host); + scsi_host_put(host); + + DPRINT_EXIT(STORVSC_DRV); + + return ret; +} + +/** + * storvsc_commmand_completion - Command completion processing + */ +static void storvsc_commmand_completion(struct hv_storvsc_request *request) +{ + struct storvsc_cmd_request *cmd_request = + (struct storvsc_cmd_request *)request->Context; + struct scsi_cmnd *scmnd = cmd_request->cmd; + struct host_device_context *host_device_ctx = + (struct host_device_context *)scmnd->device->host->hostdata; + void (*scsi_done_fn)(struct scsi_cmnd *); + struct scsi_sense_hdr sense_hdr; + + ASSERT(request == &cmd_request->request); + ASSERT((unsigned long)scmnd->host_scribble == + (unsigned long)cmd_request); + ASSERT(scmnd); + ASSERT(scmnd->scsi_done); + + DPRINT_ENTER(STORVSC_DRV); + + if (cmd_request->bounce_sgl_count) { + /* using bounce buffer */ + /* printk("copy_from_bounce_buffer\n"); */ + + /* FIXME: We can optimize on writes by just skipping this */ + copy_from_bounce_buffer(scsi_sglist(scmnd), + cmd_request->bounce_sgl, + scsi_sg_count(scmnd)); + destroy_bounce_buffer(cmd_request->bounce_sgl, + cmd_request->bounce_sgl_count); + } + + scmnd->result = request->Status; + + if (scmnd->result) { + if (scsi_normalize_sense(scmnd->sense_buffer, + request->SenseBufferSize, &sense_hdr)) + scsi_print_sense_hdr("storvsc", &sense_hdr); + } + + ASSERT(request->BytesXfer <= request->DataBuffer.Length); + scsi_set_resid(scmnd, request->DataBuffer.Length - request->BytesXfer); + + scsi_done_fn = scmnd->scsi_done; + + scmnd->host_scribble = NULL; + scmnd->scsi_done = NULL; + + /* !!DO NOT MODIFY the scmnd after this call */ + scsi_done_fn(scmnd); + + kmem_cache_free(host_device_ctx->request_pool, cmd_request); + + DPRINT_EXIT(STORVSC_DRV); +} + +static int do_bounce_buffer(struct scatterlist *sgl, unsigned int sg_count) +{ + int i; + + /* No need to check */ + if (sg_count < 2) + return -1; + + /* We have at least 2 sg entries */ + for (i = 0; i < sg_count; i++) { + if (i == 0) { + /* make sure 1st one does not have hole */ + if (sgl[i].offset + sgl[i].length != PAGE_SIZE) + return i; + } else if (i == sg_count - 1) { + /* make sure last one does not have hole */ + if (sgl[i].offset != 0) + return i; + } else { + /* make sure no hole in the middle */ + if (sgl[i].length != PAGE_SIZE || sgl[i].offset != 0) + return i; + } + } + return -1; +} + +static struct scatterlist *create_bounce_buffer(struct scatterlist *sgl, + unsigned int sg_count, + unsigned int len) +{ + int i; + int num_pages; + struct scatterlist *bounce_sgl; + struct page *page_buf; + + num_pages = ALIGN_UP(len, PAGE_SIZE) >> PAGE_SHIFT; + + bounce_sgl = kcalloc(num_pages, sizeof(struct scatterlist), GFP_ATOMIC); + if (!bounce_sgl) + return NULL; + + for (i = 0; i < num_pages; i++) { + page_buf = alloc_page(GFP_ATOMIC); + if (!page_buf) + goto cleanup; + sg_set_page(&bounce_sgl[i], page_buf, 0, 0); + } + + return bounce_sgl; + +cleanup: + destroy_bounce_buffer(bounce_sgl, num_pages); + return NULL; +} + +static void destroy_bounce_buffer(struct scatterlist *sgl, + unsigned int sg_count) +{ + int i; + struct page *page_buf; + + for (i = 0; i < sg_count; i++) { + page_buf = sg_page((&sgl[i])); + if (page_buf != NULL) + __free_page(page_buf); + } + + kfree(sgl); +} + +/* Assume the bounce_sgl has enough room ie using the create_bounce_buffer() */ +static unsigned int copy_to_bounce_buffer(struct scatterlist *orig_sgl, + struct scatterlist *bounce_sgl, + unsigned int orig_sgl_count) +{ + int i; + int j = 0; + unsigned long src, dest; + unsigned int srclen, destlen, copylen; + unsigned int total_copied = 0; + unsigned long bounce_addr = 0; + unsigned long src_addr = 0; + unsigned long flags; + + local_irq_save(flags); + + for (i = 0; i < orig_sgl_count; i++) { + src_addr = (unsigned long)kmap_atomic(sg_page((&orig_sgl[i])), + KM_IRQ0) + orig_sgl[i].offset; + src = src_addr; + srclen = orig_sgl[i].length; + + ASSERT(orig_sgl[i].offset + orig_sgl[i].length <= PAGE_SIZE); + + if (j == 0) + bounce_addr = (unsigned long)kmap_atomic(sg_page((&bounce_sgl[j])), KM_IRQ0); + + while (srclen) { + /* assume bounce offset always == 0 */ + dest = bounce_addr + bounce_sgl[j].length; + destlen = PAGE_SIZE - bounce_sgl[j].length; + + copylen = min(srclen, destlen); + memcpy((void *)dest, (void *)src, copylen); + + total_copied += copylen; + bounce_sgl[j].length += copylen; + srclen -= copylen; + src += copylen; + + if (bounce_sgl[j].length == PAGE_SIZE) { + /* full..move to next entry */ + kunmap_atomic((void *)bounce_addr, KM_IRQ0); + j++; + + /* if we need to use another bounce buffer */ + if (srclen || i != orig_sgl_count - 1) + bounce_addr = (unsigned long)kmap_atomic(sg_page((&bounce_sgl[j])), KM_IRQ0); + } else if (srclen == 0 && i == orig_sgl_count - 1) { + /* unmap the last bounce that is < PAGE_SIZE */ + kunmap_atomic((void *)bounce_addr, KM_IRQ0); + } + } + + kunmap_atomic((void *)(src_addr - orig_sgl[i].offset), KM_IRQ0); + } + + local_irq_restore(flags); + + return total_copied; +} + +/* Assume the original sgl has enough room */ +static unsigned int copy_from_bounce_buffer(struct scatterlist *orig_sgl, + struct scatterlist *bounce_sgl, + unsigned int orig_sgl_count) +{ + int i; + int j = 0; + unsigned long src, dest; + unsigned int srclen, destlen, copylen; + unsigned int total_copied = 0; + unsigned long bounce_addr = 0; + unsigned long dest_addr = 0; + unsigned long flags; + + local_irq_save(flags); + + for (i = 0; i < orig_sgl_count; i++) { + dest_addr = (unsigned long)kmap_atomic(sg_page((&orig_sgl[i])), + KM_IRQ0) + orig_sgl[i].offset; + dest = dest_addr; + destlen = orig_sgl[i].length; + ASSERT(orig_sgl[i].offset + orig_sgl[i].length <= PAGE_SIZE); + + if (j == 0) + bounce_addr = (unsigned long)kmap_atomic(sg_page((&bounce_sgl[j])), KM_IRQ0); + + while (destlen) { + src = bounce_addr + bounce_sgl[j].offset; + srclen = bounce_sgl[j].length - bounce_sgl[j].offset; + + copylen = min(srclen, destlen); + memcpy((void *)dest, (void *)src, copylen); + + total_copied += copylen; + bounce_sgl[j].offset += copylen; + destlen -= copylen; + dest += copylen; + + if (bounce_sgl[j].offset == bounce_sgl[j].length) { + /* full */ + kunmap_atomic((void *)bounce_addr, KM_IRQ0); + j++; + + /* if we need to use another bounce buffer */ + if (destlen || i != orig_sgl_count - 1) + bounce_addr = (unsigned long)kmap_atomic(sg_page((&bounce_sgl[j])), KM_IRQ0); + } else if (destlen == 0 && i == orig_sgl_count - 1) { + /* unmap the last bounce that is < PAGE_SIZE */ + kunmap_atomic((void *)bounce_addr, KM_IRQ0); + } + } + + kunmap_atomic((void *)(dest_addr - orig_sgl[i].offset), + KM_IRQ0); + } + + local_irq_restore(flags); + + return total_copied; +} + +/** + * storvsc_queuecommand - Initiate command processing + */ +static int storvsc_queuecommand(struct scsi_cmnd *scmnd, + void (*done)(struct scsi_cmnd *)) +{ + int ret; + struct host_device_context *host_device_ctx = + (struct host_device_context *)scmnd->device->host->hostdata; + struct device_context *device_ctx = host_device_ctx->device_ctx; + struct driver_context *driver_ctx = + driver_to_driver_context(device_ctx->device.driver); + struct storvsc_driver_context *storvsc_drv_ctx = + (struct storvsc_driver_context *)driver_ctx; + struct storvsc_driver_object *storvsc_drv_obj = + &storvsc_drv_ctx->drv_obj; + struct hv_storvsc_request *request; + struct storvsc_cmd_request *cmd_request; + unsigned int request_size = 0; + int i; + struct scatterlist *sgl; + + DPRINT_ENTER(STORVSC_DRV); + + DPRINT_DBG(STORVSC_DRV, "scmnd %p dir %d, use_sg %d buf %p len %d " + "queue depth %d tagged %d", scmnd, scmnd->sc_data_direction, + scsi_sg_count(scmnd), scsi_sglist(scmnd), + scsi_bufflen(scmnd), scmnd->device->queue_depth, + scmnd->device->tagged_supported); + + /* If retrying, no need to prep the cmd */ + if (scmnd->host_scribble) { + ASSERT(scmnd->scsi_done != NULL); + + cmd_request = + (struct storvsc_cmd_request *)scmnd->host_scribble; + DPRINT_INFO(STORVSC_DRV, "retrying scmnd %p cmd_request %p", + scmnd, cmd_request); + + goto retry_request; + } + + ASSERT(scmnd->scsi_done == NULL); + ASSERT(scmnd->host_scribble == NULL); + + scmnd->scsi_done = done; + + request_size = sizeof(struct storvsc_cmd_request); + + cmd_request = kmem_cache_alloc(host_device_ctx->request_pool, + GFP_ATOMIC); + if (!cmd_request) { + DPRINT_ERR(STORVSC_DRV, "scmnd (%p) - unable to allocate " + "storvsc_cmd_request...marking queue busy", scmnd); + scmnd->scsi_done = NULL; + return SCSI_MLQUEUE_DEVICE_BUSY; + } + + /* Setup the cmd request */ + cmd_request->bounce_sgl_count = 0; + cmd_request->bounce_sgl = NULL; + cmd_request->cmd = scmnd; + + scmnd->host_scribble = (unsigned char *)cmd_request; + + request = &cmd_request->request; + + request->Extension = + (void *)((unsigned long)cmd_request + request_size); + DPRINT_DBG(STORVSC_DRV, "req %p size %d ext %d", request, request_size, + storvsc_drv_obj->RequestExtSize); + + /* Build the SRB */ + switch (scmnd->sc_data_direction) { + case DMA_TO_DEVICE: + request->Type = WRITE_TYPE; + break; + case DMA_FROM_DEVICE: + request->Type = READ_TYPE; + break; + default: + request->Type = UNKNOWN_TYPE; + break; + } + + request->OnIOCompletion = storvsc_commmand_completion; + request->Context = cmd_request;/* scmnd; */ + + /* request->PortId = scmnd->device->channel; */ + request->Host = host_device_ctx->port; + request->Bus = scmnd->device->channel; + request->TargetId = scmnd->device->id; + request->LunId = scmnd->device->lun; + + ASSERT(scmnd->cmd_len <= 16); + request->CdbLen = scmnd->cmd_len; + request->Cdb = scmnd->cmnd; + + request->SenseBuffer = scmnd->sense_buffer; + request->SenseBufferSize = SCSI_SENSE_BUFFERSIZE; + + + request->DataBuffer.Length = scsi_bufflen(scmnd); + if (scsi_sg_count(scmnd)) { + sgl = (struct scatterlist *)scsi_sglist(scmnd); + + /* check if we need to bounce the sgl */ + if (do_bounce_buffer(sgl, scsi_sg_count(scmnd)) != -1) { + DPRINT_INFO(STORVSC_DRV, + "need to bounce buffer for this scmnd %p", + scmnd); + cmd_request->bounce_sgl = + create_bounce_buffer(sgl, scsi_sg_count(scmnd), + scsi_bufflen(scmnd)); + if (!cmd_request->bounce_sgl) { + DPRINT_ERR(STORVSC_DRV, + "unable to create bounce buffer for " + "this scmnd %p", scmnd); + + scmnd->scsi_done = NULL; + scmnd->host_scribble = NULL; + kmem_cache_free(host_device_ctx->request_pool, + cmd_request); + + return SCSI_MLQUEUE_HOST_BUSY; + } + + cmd_request->bounce_sgl_count = + ALIGN_UP(scsi_bufflen(scmnd), PAGE_SIZE) >> + PAGE_SHIFT; + + /* + * FIXME: We can optimize on reads by just skipping + * this + */ + copy_to_bounce_buffer(sgl, cmd_request->bounce_sgl, + scsi_sg_count(scmnd)); + + sgl = cmd_request->bounce_sgl; + } + + request->DataBuffer.Offset = sgl[0].offset; + + for (i = 0; i < scsi_sg_count(scmnd); i++) { + DPRINT_DBG(STORVSC_DRV, "sgl[%d] len %d offset %d \n", + i, sgl[i].length, sgl[i].offset); + request->DataBuffer.PfnArray[i] = + page_to_pfn(sg_page((&sgl[i]))); + } + } else if (scsi_sglist(scmnd)) { + ASSERT(scsi_bufflen(scmnd) <= PAGE_SIZE); + request->DataBuffer.Offset = + virt_to_phys(scsi_sglist(scmnd)) & (PAGE_SIZE-1); + request->DataBuffer.PfnArray[0] = + virt_to_phys(scsi_sglist(scmnd)) >> PAGE_SHIFT; + } else { + ASSERT(scsi_bufflen(scmnd) == 0); + } + +retry_request: + /* Invokes the vsc to start an IO */ + ret = storvsc_drv_obj->OnIORequest(&device_ctx->device_obj, + &cmd_request->request); + if (ret == -1) { + /* no more space */ + DPRINT_ERR(STORVSC_DRV, + "scmnd (%p) - queue FULL...marking queue busy", + scmnd); + + if (cmd_request->bounce_sgl_count) { + /* + * FIXME: We can optimize on writes by just skipping + * this + */ + copy_from_bounce_buffer(scsi_sglist(scmnd), + cmd_request->bounce_sgl, + scsi_sg_count(scmnd)); + destroy_bounce_buffer(cmd_request->bounce_sgl, + cmd_request->bounce_sgl_count); + } + + kmem_cache_free(host_device_ctx->request_pool, cmd_request); + + scmnd->scsi_done = NULL; + scmnd->host_scribble = NULL; + + ret = SCSI_MLQUEUE_DEVICE_BUSY; + } + + DPRINT_EXIT(STORVSC_DRV); + + return ret; +} + +static int storvsc_merge_bvec(struct request_queue *q, + struct bvec_merge_data *bmd, struct bio_vec *bvec) +{ + /* checking done by caller. */ + return bvec->bv_len; +} + +/** + * storvsc_device_configure - Configure the specified scsi device + */ +static int storvsc_device_alloc(struct scsi_device *sdevice) +{ + DPRINT_DBG(STORVSC_DRV, "sdev (%p) - setting device flag to %d", + sdevice, BLIST_SPARSELUN); + /* + * This enables luns to be located sparsely. Otherwise, we may not + * discovered them. + */ + sdevice->sdev_bflags |= BLIST_SPARSELUN | BLIST_LARGELUN; + return 0; +} + +static int storvsc_device_configure(struct scsi_device *sdevice) +{ + DPRINT_INFO(STORVSC_DRV, "sdev (%p) - curr queue depth %d", sdevice, + sdevice->queue_depth); + + DPRINT_INFO(STORVSC_DRV, "sdev (%p) - setting queue depth to %d", + sdevice, STORVSC_MAX_IO_REQUESTS); + scsi_adjust_queue_depth(sdevice, MSG_SIMPLE_TAG, + STORVSC_MAX_IO_REQUESTS); + + DPRINT_INFO(STORVSC_DRV, "sdev (%p) - setting max segment size to %ld", + sdevice, PAGE_SIZE); + blk_queue_max_segment_size(sdevice->request_queue, PAGE_SIZE); + + DPRINT_INFO(STORVSC_DRV, "sdev (%p) - adding merge bio vec routine", + sdevice); + blk_queue_merge_bvec(sdevice->request_queue, storvsc_merge_bvec); + + blk_queue_bounce_limit(sdevice->request_queue, BLK_BOUNCE_ANY); + /* sdevice->timeout = (2000 * HZ);//(75 * HZ); */ + + return 0; +} + +/** + * storvsc_host_reset_handler - Reset the scsi HBA + */ +static int storvsc_host_reset_handler(struct scsi_cmnd *scmnd) +{ + int ret; + struct host_device_context *host_device_ctx = + (struct host_device_context *)scmnd->device->host->hostdata; + struct device_context *device_ctx = host_device_ctx->device_ctx; + struct driver_context *driver_ctx = + driver_to_driver_context(device_ctx->device.driver); + struct storvsc_driver_context *storvsc_drv_ctx = + (struct storvsc_driver_context *)driver_ctx; + + struct storvsc_driver_object *storvsc_drv_obj = + &storvsc_drv_ctx->drv_obj; + + DPRINT_ENTER(STORVSC_DRV); + + DPRINT_INFO(STORVSC_DRV, "sdev (%p) dev obj (%p) - host resetting...", + scmnd->device, &device_ctx->device_obj); + + /* Invokes the vsc to reset the host/bus */ + ASSERT(storvsc_drv_obj->OnHostReset); + ret = storvsc_drv_obj->OnHostReset(&device_ctx->device_obj); + if (ret != 0) { + DPRINT_EXIT(STORVSC_DRV); + return ret; + } + + DPRINT_INFO(STORVSC_DRV, "sdev (%p) dev obj (%p) - host reseted", + scmnd->device, &device_ctx->device_obj); + + DPRINT_EXIT(STORVSC_DRV); + + return ret; +} + +/** + * storvsc_host_rescan - Rescan the scsi HBA + */ +static void storvsc_host_rescan_callback(struct work_struct *work) +{ + struct hv_device *device_obj = + &((struct host_device_context *)work)->device_ctx->device_obj; + struct device_context *device_ctx = to_device_context(device_obj); + struct Scsi_Host *host = dev_get_drvdata(&device_ctx->device); + struct scsi_device *sdev; + struct host_device_context *host_device_ctx; + struct scsi_device **sdevs_remove_list; + unsigned int sdevs_count = 0; + unsigned int found; + unsigned int i; + unsigned int lun_count = 0; + unsigned int *lun_list; + + DPRINT_ENTER(STORVSC_DRV); + + host_device_ctx = (struct host_device_context *)host->hostdata; + lun_list = kcalloc(STORVSC_MAX_LUNS_PER_TARGET, sizeof(unsigned int), + GFP_ATOMIC); + if (!lun_list) { + DPRINT_ERR(STORVSC_DRV, "unable to allocate lun list"); + return; + } + + sdevs_remove_list = kcalloc(STORVSC_MAX_LUNS_PER_TARGET, + sizeof(void *), GFP_ATOMIC); + if (!sdevs_remove_list) { + kfree(lun_list); + DPRINT_ERR(STORVSC_DRV, "unable to allocate lun remove list"); + return; + } + + DPRINT_INFO(STORVSC_DRV, "rescanning host for new scsi devices..."); + + /* Rescan for new device */ + scsi_scan_target(&host->shost_gendev, host_device_ctx->path, + host_device_ctx->target, SCAN_WILD_CARD, 1); + + DPRINT_INFO(STORVSC_DRV, "rescanning host for removed scsi device..."); + + /* Use the 1st device to send the report luns cmd */ + shost_for_each_device(sdev, host) { + lun_count = STORVSC_MAX_LUNS_PER_TARGET; + storvsc_report_luns(sdev, lun_list, &lun_count); + + DPRINT_INFO(STORVSC_DRV, + "report luns on scsi device (%p) found %u luns ", + sdev, lun_count); + DPRINT_INFO(STORVSC_DRV, + "existing luns on scsi device (%p) host (%d)", + sdev, host->host_no); + + scsi_device_put(sdev); + break; + } + + for (i = 0; i < lun_count; i++) + DPRINT_INFO(STORVSC_DRV, "%d) lun %u", i, lun_list[i]); + + /* Rescan for devices that may have been removed. + * We do not have to worry that new devices may have been added since + * this callback is serialized by the workqueue ie add/remove are done + * here. + */ + shost_for_each_device(sdev, host) { + /* See if this device is still here */ + found = 0; + for (i = 0; i < lun_count; i++) { + if (sdev->lun == lun_list[i]) { + found = 1; + break; + } + } + if (!found) { + DPRINT_INFO(STORVSC_DRV, "lun (%u) does not exists", + sdev->lun); + sdevs_remove_list[sdevs_count++] = sdev; + } + } + + /* Now remove the devices */ + for (i = 0; i < sdevs_count; i++) { + DPRINT_INFO(STORVSC_DRV, + "removing scsi device (%p) lun (%u)...", + sdevs_remove_list[i], sdevs_remove_list[i]->lun); + + /* make sure it is not removed from underneath us */ + if (!scsi_device_get(sdevs_remove_list[i])) { + scsi_remove_device(sdevs_remove_list[i]); + scsi_device_put(sdevs_remove_list[i]); + } + } + + DPRINT_INFO(STORVSC_DRV, "rescan completed on dev obj (%p) " + "target (%u) bus (%u)", device_obj, + host_device_ctx->target, host_device_ctx->path); + + kfree(lun_list); + kfree(sdevs_remove_list); + + DPRINT_EXIT(STORVSC_DRV); +} + +static int storvsc_report_luns(struct scsi_device *sdev, unsigned int luns[], + unsigned int *lun_count) +{ + int i, j; + unsigned int lun = 0; + unsigned int num_luns; + int result; + unsigned char *data; + struct scsi_sense_hdr sshdr; + unsigned char cmd[16] = {0}; + /* Add 1 to cover the report_lun header */ + unsigned int report_len = 8 * (STORVSC_MAX_LUNS_PER_TARGET+1); + unsigned long long *report_luns; + const unsigned int in_lun_count = *lun_count; + + *lun_count = 0; + + report_luns = kzalloc(report_len, GFP_ATOMIC); + if (!report_luns) + return -ENOMEM; + + cmd[0] = REPORT_LUNS; + + /* cmd length */ + *(unsigned int *)&cmd[6] = cpu_to_be32(report_len); + + result = scsi_execute_req(sdev, cmd, DMA_FROM_DEVICE, + (unsigned char *)report_luns, report_len, + &sshdr, 30 * HZ, 3, NULL); + if (result != 0) { + kfree(report_luns); + return -EBUSY; + } + + /* get the length from the first four bytes */ + report_len = be32_to_cpu(*(unsigned int *)&report_luns[0]); + + num_luns = (report_len / sizeof(unsigned long long)); + if (num_luns > in_lun_count) { + kfree(report_luns); + return -EINVAL; + } + + *lun_count = num_luns; + + DPRINT_DBG(STORVSC_DRV, + "report luns on scsi device (%p) found %u luns ", + sdev, num_luns); + + /* lun id starts at 1 */ + for (i = 1; i < num_luns + 1; i++) { + lun = 0; + data = (unsigned char *)&report_luns[i]; + for (j = 0; j < sizeof(lun); j += 2) { + lun = lun | (((data[j] << 8) | data[j + 1]) << + (j * 8)); + } + + luns[i-1] = lun; + } + + kfree(report_luns); + return 0; +} + +static void storvsc_host_rescan(struct hv_device *device_obj) +{ + struct device_context *device_ctx = to_device_context(device_obj); + struct Scsi_Host *host = dev_get_drvdata(&device_ctx->device); + struct host_device_context *host_device_ctx; + + DPRINT_ENTER(STORVSC_DRV); + + host_device_ctx = (struct host_device_context *)host->hostdata; + + DPRINT_INFO(STORVSC_DRV, "initiating rescan on dev obj (%p) " + "target (%u) bus (%u)...", device_obj, + host_device_ctx->target, host_device_ctx->path); + + /* + * We need to queue this since the scanning may block and the caller + * may be in an intr context + */ + /* scsi_queue_work(host, &host_device_ctx->host_rescan_work); */ + schedule_work(&host_device_ctx->host_rescan_work); + DPRINT_EXIT(STORVSC_DRV); +} + +static int storvsc_get_chs(struct scsi_device *sdev, struct block_device * bdev, + sector_t capacity, int *info) +{ + sector_t total_sectors = capacity; + sector_t cylinder_times_heads = 0; + sector_t temp = 0; + + int sectors_per_track = 0; + int heads = 0; + int cylinders = 0; + int rem = 0; + + if (total_sectors > (65535 * 16 * 255)) + total_sectors = (65535 * 16 * 255); + + if (total_sectors >= (65535 * 16 * 63)) { + sectors_per_track = 255; + heads = 16; + + cylinder_times_heads = total_sectors; + /* sector_div stores the quotient in cylinder_times_heads */ + rem = sector_div(cylinder_times_heads, sectors_per_track); + } else { + sectors_per_track = 17; + + cylinder_times_heads = total_sectors; + /* sector_div stores the quotient in cylinder_times_heads */ + rem = sector_div(cylinder_times_heads, sectors_per_track); + + temp = cylinder_times_heads + 1023; + /* sector_div stores the quotient in temp */ + rem = sector_div(temp, 1024); + + heads = temp; + + if (heads < 4) + heads = 4; + + if (cylinder_times_heads >= (heads * 1024) || (heads > 16)) { + sectors_per_track = 31; + heads = 16; + + cylinder_times_heads = total_sectors; + /* + * sector_div stores the quotient in + * cylinder_times_heads + */ + rem = sector_div(cylinder_times_heads, + sectors_per_track); + } + + if (cylinder_times_heads >= (heads * 1024)) { + sectors_per_track = 63; + heads = 16; + + cylinder_times_heads = total_sectors; + /* + * sector_div stores the quotient in + * cylinder_times_heads + */ + rem = sector_div(cylinder_times_heads, + sectors_per_track); + } + } + + temp = cylinder_times_heads; + /* sector_div stores the quotient in temp */ + rem = sector_div(temp, heads); + cylinders = temp; + + info[0] = heads; + info[1] = sectors_per_track; + info[2] = cylinders; + + DPRINT_INFO(STORVSC_DRV, "CHS (%d, %d, %d)", cylinders, heads, + sectors_per_track); + + return 0; +} + +static int __init storvsc_init(void) +{ + int ret; + + DPRINT_ENTER(STORVSC_DRV); + DPRINT_INFO(STORVSC_DRV, "Storvsc initializing...."); + ret = storvsc_drv_init(StorVscInitialize); + DPRINT_EXIT(STORVSC_DRV); + return ret; +} + +static void __exit storvsc_exit(void) +{ + DPRINT_ENTER(STORVSC_DRV); + storvsc_drv_exit(); + DPRINT_ENTER(STORVSC_DRV); +} + +MODULE_LICENSE("GPL"); +module_param(storvsc_ringbuffer_size, int, S_IRUGO); +module_init(storvsc_init); +module_exit(storvsc_exit); |