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Subject[PATCH 08/15] Staging: hv: storvsc: Get rid of the on_io_completion in hv_storvsc_request
Date
Get rid of the on_io_completion field  in struct hv_storvsc_request. As part of this
relocate the bounce buffer handling code (to avoid having forward declarations).

Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
---
drivers/staging/hv/storvsc_drv.c | 630 +++++++++++++++++++-------------------
1 files changed, 313 insertions(+), 317 deletions(-)
diff --git a/drivers/staging/hv/storvsc_drv.c b/drivers/staging/hv/storvsc_drv.c
index 204b3ca..7c9fa19 100644
--- a/drivers/staging/hv/storvsc_drv.c
+++ b/drivers/staging/hv/storvsc_drv.c
@@ -276,7 +276,6 @@ struct hv_storvsc_request {

unsigned char *sense_buffer;
void *context;
- void (*on_io_completion)(struct hv_storvsc_request *request);
struct hv_multipage_buffer data_buffer;

struct vstor_packet vstor_packet;
@@ -436,6 +435,227 @@ get_in_err:

}

+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);
+}
+
+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 write)
+{
+ int i;
+ int num_pages;
+ struct scatterlist *bounce_sgl;
+ struct page *page_buf;
+ unsigned int buf_len = ((write == WRITE_TYPE) ? 0 : PAGE_SIZE);
+
+ num_pages = ALIGN(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, buf_len, 0);
+ }
+
+ return bounce_sgl;
+
+cleanup:
+ destroy_bounce_buffer(bounce_sgl, num_pages);
+ return NULL;
+}
+
+/* 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,
+ unsigned int bounce_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;
+
+ if (bounce_addr == 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++;
+
+ /*
+ * It is possible that the number of elements
+ * in the bounce buffer may not be equal to
+ * the number of elements in the original
+ * scatter list. Handle this correctly.
+ */
+
+ if (j == bounce_sgl_count) {
+ /*
+ * We are done; cleanup and return.
+ */
+ kunmap_atomic((void *)(dest_addr -
+ orig_sgl[i].offset),
+ KM_IRQ0);
+ local_irq_restore(flags);
+ return total_copied;
+ }
+
+ /* 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;
+}
+
+/* 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;
+
+ if (bounce_addr == 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;
+}
+
static int storvsc_channel_init(struct hv_device *device)
{
struct storvsc_device *stor_device;
@@ -562,24 +782,101 @@ cleanup:
return ret;
}

-static void storvsc_on_io_completion(struct hv_device *device,
- struct vstor_packet *vstor_packet,
- struct hv_storvsc_request *request)
+
+static void storvsc_command_completion(struct hv_storvsc_request *request)
{
- struct storvsc_device *stor_device;
- struct vstor_packet *stor_pkt;
+ struct storvsc_cmd_request *cmd_request =
+ (struct storvsc_cmd_request *)request->context;
+ struct scsi_cmnd *scmnd = cmd_request->cmd;
+ struct hv_host_device *host_dev = shost_priv(scmnd->device->host);
+ void (*scsi_done_fn)(struct scsi_cmnd *);
+ struct scsi_sense_hdr sense_hdr;
+ struct vmscsi_request *vm_srb;
+ struct storvsc_scan_work *wrk;
+ struct stor_mem_pools *memp = scmnd->device->hostdata;

- stor_device = hv_get_drvdata(device);
- stor_pkt = &request->vstor_packet;
+ vm_srb = &request->vstor_packet.vm_srb;
+ if (cmd_request->bounce_sgl_count) {
+ if (vm_srb->data_in == READ_TYPE)
+ copy_from_bounce_buffer(scsi_sglist(scmnd),
+ cmd_request->bounce_sgl,
+ scsi_sg_count(scmnd),
+ cmd_request->bounce_sgl_count);
+ destroy_bounce_buffer(cmd_request->bounce_sgl,
+ cmd_request->bounce_sgl_count);
+ }

/*
- * The current SCSI handling on the host side does
- * not correctly handle:
- * INQUIRY command with page code parameter set to 0x80
- * MODE_SENSE command with cmd[2] == 0x1c
- *
- * Setup srb and scsi status so this won't be fatal.
- * We do this so we can distinguish truly fatal failues
+ * If there is an error; offline the device since all
+ * error recovery strategies would have already been
+ * deployed on the host side.
+ */
+ if (vm_srb->srb_status == SRB_STATUS_ERROR)
+ scmnd->result = DID_TARGET_FAILURE << 16;
+ else
+ scmnd->result = vm_srb->scsi_status;
+
+ /*
+ * If the LUN is invalid; remove the device.
+ */
+ if (vm_srb->srb_status == SRB_STATUS_INVALID_LUN) {
+ struct storvsc_device *stor_dev;
+ struct hv_device *dev = host_dev->dev;
+ struct Scsi_Host *host;
+
+ stor_dev = get_in_stor_device(dev);
+ host = stor_dev->host;
+
+ wrk = kmalloc(sizeof(struct storvsc_scan_work),
+ GFP_ATOMIC);
+ if (!wrk) {
+ scmnd->result = DID_TARGET_FAILURE << 16;
+ } else {
+ wrk->host = host;
+ wrk->lun = vm_srb->lun;
+ INIT_WORK(&wrk->work, storvsc_remove_lun);
+ schedule_work(&wrk->work);
+ }
+ }
+
+ if (scmnd->result) {
+ if (scsi_normalize_sense(scmnd->sense_buffer,
+ SCSI_SENSE_BUFFERSIZE, &sense_hdr))
+ scsi_print_sense_hdr("storvsc", &sense_hdr);
+ }
+
+ scsi_set_resid(scmnd,
+ request->data_buffer.len -
+ vm_srb->data_transfer_length);
+
+ scsi_done_fn = scmnd->scsi_done;
+
+ scmnd->host_scribble = NULL;
+ scmnd->scsi_done = NULL;
+
+ scsi_done_fn(scmnd);
+
+ mempool_free(cmd_request, memp->request_mempool);
+}
+
+static void storvsc_on_io_completion(struct hv_device *device,
+ struct vstor_packet *vstor_packet,
+ struct hv_storvsc_request *request)
+{
+ struct storvsc_device *stor_device;
+ struct vstor_packet *stor_pkt;
+
+ stor_device = hv_get_drvdata(device);
+ stor_pkt = &request->vstor_packet;
+
+ /*
+ * The current SCSI handling on the host side does
+ * not correctly handle:
+ * INQUIRY command with page code parameter set to 0x80
+ * MODE_SENSE command with cmd[2] == 0x1c
+ *
+ * Setup srb and scsi status so this won't be fatal.
+ * We do this so we can distinguish truly fatal failues
* (srb status == 0x4) and off-line the device in that case.
*/

@@ -625,7 +922,7 @@ static void storvsc_on_io_completion(struct hv_device *device,
stor_pkt->vm_srb.data_transfer_length =
vstor_packet->vm_srb.data_transfer_length;

- request->on_io_completion(request);
+ storvsc_command_completion(request);

if (atomic_dec_and_test(&stor_device->num_outstanding_req) &&
stor_device->drain_notify)
@@ -875,229 +1172,6 @@ static int storvsc_device_configure(struct scsi_device *sdevice)
return 0;
}

-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);
-}
-
-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 write)
-{
- int i;
- int num_pages;
- struct scatterlist *bounce_sgl;
- struct page *page_buf;
- unsigned int buf_len = ((write == WRITE_TYPE) ? 0 : PAGE_SIZE);
-
- num_pages = ALIGN(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, buf_len, 0);
- }
-
- return bounce_sgl;
-
-cleanup:
- destroy_bounce_buffer(bounce_sgl, num_pages);
- return NULL;
-}
-
-
-/* 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,
- unsigned int bounce_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;
-
- if (bounce_addr == 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++;
-
- /*
- * It is possible that the number of elements
- * in the bounce buffer may not be equal to
- * the number of elements in the original
- * scatter list. Handle this correctly.
- */
-
- if (j == bounce_sgl_count) {
- /*
- * We are done; cleanup and return.
- */
- kunmap_atomic((void *)(dest_addr -
- orig_sgl[i].offset),
- KM_IRQ0);
- local_irq_restore(flags);
- return total_copied;
- }
-
- /* 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;
-}
-
-
-/* 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;
-
- if (bounce_addr == 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;
-}
-
static int storvsc_get_chs(struct scsi_device *sdev, struct block_device * bdev,
sector_t capacity, int *info)
{
@@ -1166,83 +1240,6 @@ static int storvsc_host_reset_handler(struct scsi_cmnd *scmnd)
return SUCCESS;
}

-
-static void storvsc_command_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 hv_host_device *host_dev = shost_priv(scmnd->device->host);
- void (*scsi_done_fn)(struct scsi_cmnd *);
- struct scsi_sense_hdr sense_hdr;
- struct vmscsi_request *vm_srb;
- struct storvsc_scan_work *wrk;
- struct stor_mem_pools *memp = scmnd->device->hostdata;
-
- vm_srb = &request->vstor_packet.vm_srb;
- if (cmd_request->bounce_sgl_count) {
- if (vm_srb->data_in == READ_TYPE)
- copy_from_bounce_buffer(scsi_sglist(scmnd),
- cmd_request->bounce_sgl,
- scsi_sg_count(scmnd),
- cmd_request->bounce_sgl_count);
- destroy_bounce_buffer(cmd_request->bounce_sgl,
- cmd_request->bounce_sgl_count);
- }
-
- /*
- * If there is an error; offline the device since all
- * error recovery strategies would have already been
- * deployed on the host side.
- */
- if (vm_srb->srb_status == SRB_STATUS_ERROR)
- scmnd->result = DID_TARGET_FAILURE << 16;
- else
- scmnd->result = vm_srb->scsi_status;
-
- /*
- * If the LUN is invalid; remove the device.
- */
- if (vm_srb->srb_status == SRB_STATUS_INVALID_LUN) {
- struct storvsc_device *stor_dev;
- struct hv_device *dev = host_dev->dev;
- struct Scsi_Host *host;
-
- stor_dev = get_in_stor_device(dev);
- host = stor_dev->host;
-
- wrk = kmalloc(sizeof(struct storvsc_scan_work),
- GFP_ATOMIC);
- if (!wrk) {
- scmnd->result = DID_TARGET_FAILURE << 16;
- } else {
- wrk->host = host;
- wrk->lun = vm_srb->lun;
- INIT_WORK(&wrk->work, storvsc_remove_lun);
- schedule_work(&wrk->work);
- }
- }
-
- if (scmnd->result) {
- if (scsi_normalize_sense(scmnd->sense_buffer,
- SCSI_SENSE_BUFFERSIZE, &sense_hdr))
- scsi_print_sense_hdr("storvsc", &sense_hdr);
- }
-
- scsi_set_resid(scmnd,
- request->data_buffer.len -
- vm_srb->data_transfer_length);
-
- scsi_done_fn = scmnd->scsi_done;
-
- scmnd->host_scribble = NULL;
- scmnd->scsi_done = NULL;
-
- scsi_done_fn(scmnd);
-
- mempool_free(cmd_request, memp->request_mempool);
-}
-
static bool storvsc_scsi_cmd_ok(struct scsi_cmnd *scmnd)
{
bool allowed = true;
@@ -1318,7 +1315,6 @@ static int storvsc_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *scmnd)
break;
}

- request->on_io_completion = storvsc_command_completion;
request->context = cmd_request;/* scmnd; */

vm_srb->port_number = host_dev->port;
--
1.7.4.1


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