diff options
Diffstat (limited to 'drivers/scsi/storvsc_drv.c')
| -rw-r--r-- | drivers/scsi/storvsc_drv.c | 66 |
1 files changed, 23 insertions, 43 deletions
diff --git a/drivers/scsi/storvsc_drv.c b/drivers/scsi/storvsc_drv.c index dfe005c03734..e6718a74e5da 100644 --- a/drivers/scsi/storvsc_drv.c +++ b/drivers/scsi/storvsc_drv.c @@ -1692,9 +1692,8 @@ static int storvsc_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *scmnd) struct storvsc_cmd_request *cmd_request = scsi_cmd_priv(scmnd); int i; struct scatterlist *sgl; - unsigned int sg_count = 0; + unsigned int sg_count; struct vmscsi_request *vm_srb; - struct scatterlist *cur_sgl; struct vmbus_packet_mpb_array *payload; u32 payload_sz; u32 length; @@ -1773,8 +1772,8 @@ static int storvsc_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *scmnd) payload_sz = sizeof(cmd_request->mpb); if (sg_count) { - unsigned int hvpgoff = 0; - unsigned long offset_in_hvpg = sgl->offset & ~HV_HYP_PAGE_MASK; + unsigned int hvpgoff, hvpfns_to_add; + unsigned long offset_in_hvpg = offset_in_hvpage(sgl->offset); unsigned int hvpg_count = HVPFN_UP(offset_in_hvpg + length); u64 hvpfn; @@ -1787,51 +1786,34 @@ static int storvsc_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *scmnd) return SCSI_MLQUEUE_DEVICE_BUSY; } - /* - * sgl is a list of PAGEs, and payload->range.pfn_array - * expects the page number in the unit of HV_HYP_PAGE_SIZE (the - * page size that Hyper-V uses, so here we need to divide PAGEs - * into HV_HYP_PAGE in case that PAGE_SIZE > HV_HYP_PAGE_SIZE. - * Besides, payload->range.offset should be the offset in one - * HV_HYP_PAGE. - */ payload->range.len = length; payload->range.offset = offset_in_hvpg; - hvpgoff = sgl->offset >> HV_HYP_PAGE_SHIFT; - cur_sgl = sgl; - for (i = 0; i < hvpg_count; i++) { + + for (i = 0; sgl != NULL; sgl = sg_next(sgl)) { /* - * 'i' is the index of hv pages in the payload and - * 'hvpgoff' is the offset (in hv pages) of the first - * hv page in the the first page. The relationship - * between the sum of 'i' and 'hvpgoff' and the offset - * (in hv pages) in a payload page ('hvpgoff_in_page') - * is as follow: - * - * |------------------ PAGE -------------------| - * | NR_HV_HYP_PAGES_IN_PAGE hvpgs in total | - * |hvpg|hvpg| ... |hvpg|... |hvpg| - * ^ ^ ^ ^ - * +-hvpgoff-+ +-hvpgoff_in_page-+ - * ^ | - * +--------------------- i ---------------------------+ + * Init values for the current sgl entry. hvpgoff + * and hvpfns_to_add are in units of Hyper-V size + * pages. Handling the PAGE_SIZE != HV_HYP_PAGE_SIZE + * case also handles values of sgl->offset that are + * larger than PAGE_SIZE. Such offsets are handled + * even on other than the first sgl entry, provided + * they are a multiple of PAGE_SIZE. */ - unsigned int hvpgoff_in_page = - (i + hvpgoff) % NR_HV_HYP_PAGES_IN_PAGE; + hvpgoff = HVPFN_DOWN(sgl->offset); + hvpfn = page_to_hvpfn(sg_page(sgl)) + hvpgoff; + hvpfns_to_add = HVPFN_UP(sgl->offset + sgl->length) - + hvpgoff; /* - * Two cases that we need to fetch a page: - * 1) i == 0, the first step or - * 2) hvpgoff_in_page == 0, when we reach the boundary - * of a page. + * Fill the next portion of the PFN array with + * sequential Hyper-V PFNs for the continguous physical + * memory described by the sgl entry. The end of the + * last sgl should be reached at the same time that + * the PFN array is filled. */ - if (hvpgoff_in_page == 0 || i == 0) { - hvpfn = page_to_hvpfn(sg_page(cur_sgl)); - cur_sgl = sg_next(cur_sgl); - } - - payload->range.pfn_array[i] = hvpfn + hvpgoff_in_page; + while (hvpfns_to_add--) + payload->range.pfn_array[i++] = hvpfn++; } } @@ -1865,8 +1847,6 @@ static struct scsi_host_template scsi_driver = { .slave_configure = storvsc_device_configure, .cmd_per_lun = 2048, .this_id = -1, - /* Make sure we dont get a sg segment crosses a page boundary */ - .dma_boundary = PAGE_SIZE-1, /* Ensure there are no gaps in presented sgls */ .virt_boundary_mask = PAGE_SIZE-1, .no_write_same = 1, |