> -----Original Message----- > From: devel [mailto:driverdev-devel-bounces@xxxxxxxxxxxxxxxxxxxxxx] On > Behalf Of K. Y. Srinivasan > Sent: Monday, March 23, 2015 2:07 PM > To: gregkh@xxxxxxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; > devel@xxxxxxxxxxxxxxxxxxxxxx; ohering@xxxxxxxx; jbottomley@xxxxxxxxxxxxx; > hch@xxxxxxxxxxxxx; linux-scsi@xxxxxxxxxxxxxxx; apw@xxxxxxxxxxxxx; > vkuznets@xxxxxxxxxx; jasowang@xxxxxxxxxx > Subject: [PATCH 6/7] scsi: storvsc: Don't assume that the scatterlist is not > chained > > The current code assumes that the scatterlists presented are not chained. > Fix the code to not make this assumption. > > Signed-off-by: K. Y. Srinivasan <kys@xxxxxxxxxxxxx> Reviewed-by: Long Li <longli@xxxxxxxxxxxxx> > --- > drivers/scsi/storvsc_drv.c | 98 +++++++++++++++++++++++++------------------ > 1 files changed, 57 insertions(+), 41 deletions(-) > > diff --git a/drivers/scsi/storvsc_drv.c b/drivers/scsi/storvsc_drv.c index > 88f5d79..a599677 100644 > --- a/drivers/scsi/storvsc_drv.c > +++ b/drivers/scsi/storvsc_drv.c > @@ -626,19 +626,6 @@ cleanup: > return NULL; > } > > -/* Disgusting wrapper functions */ > -static inline unsigned long sg_kmap_atomic(struct scatterlist *sgl, int idx) -{ > - void *addr = kmap_atomic(sg_page(sgl + idx)); > - return (unsigned long)addr; > -} > - > -static inline void sg_kunmap_atomic(unsigned long addr) -{ > - kunmap_atomic((void *)addr); > -} > - > - > /* Assume the original sgl has enough room */ static unsigned int > copy_from_bounce_buffer(struct scatterlist *orig_sgl, > struct scatterlist *bounce_sgl, @@ - > 653,32 +640,39 @@ static unsigned int copy_from_bounce_buffer(struct > scatterlist *orig_sgl, > unsigned long bounce_addr = 0; > unsigned long dest_addr = 0; > unsigned long flags; > + struct scatterlist *cur_dest_sgl; > + struct scatterlist *cur_src_sgl; > > local_irq_save(flags); > - > + cur_dest_sgl = orig_sgl; > + cur_src_sgl = bounce_sgl; > for (i = 0; i < orig_sgl_count; i++) { > - dest_addr = sg_kmap_atomic(orig_sgl,i) + orig_sgl[i].offset; > + dest_addr = (unsigned long) > + kmap_atomic(sg_page(cur_dest_sgl)) + > + cur_dest_sgl->offset; > dest = dest_addr; > destlen = orig_sgl[i].length; > + destlen = cur_dest_sgl->length; > > if (bounce_addr == 0) > - bounce_addr = sg_kmap_atomic(bounce_sgl,j); > + bounce_addr = (unsigned long)kmap_atomic( > + sg_page(cur_src_sgl)); > > while (destlen) { > - src = bounce_addr + bounce_sgl[j].offset; > - srclen = bounce_sgl[j].length - bounce_sgl[j].offset; > + src = bounce_addr + cur_src_sgl->offset; > + srclen = cur_src_sgl->length - cur_src_sgl->offset; > > copylen = min(srclen, destlen); > memcpy((void *)dest, (void *)src, copylen); > > total_copied += copylen; > - bounce_sgl[j].offset += copylen; > + cur_src_sgl->offset += copylen; > destlen -= copylen; > dest += copylen; > > - if (bounce_sgl[j].offset == bounce_sgl[j].length) { > + if (cur_src_sgl->offset == cur_src_sgl->length) { > /* full */ > - sg_kunmap_atomic(bounce_addr); > + kunmap_atomic((void *)bounce_addr); > j++; > > /* > @@ -692,21 +686,27 @@ static unsigned int copy_from_bounce_buffer(struct > scatterlist *orig_sgl, > /* > * We are done; cleanup and return. > */ > - sg_kunmap_atomic(dest_addr - > orig_sgl[i].offset); > + kunmap_atomic((void *)(dest_addr - > + cur_dest_sgl->offset)); > local_irq_restore(flags); > return total_copied; > } > > /* if we need to use another bounce buffer */ > - if (destlen || i != orig_sgl_count - 1) > - bounce_addr = > sg_kmap_atomic(bounce_sgl,j); > + if (destlen || i != orig_sgl_count - 1) { > + cur_src_sgl = sg_next(cur_src_sgl); > + bounce_addr = (unsigned long) > + kmap_atomic( > + sg_page(cur_src_sgl)); > + } > } else if (destlen == 0 && i == orig_sgl_count - 1) { > /* unmap the last bounce that is < PAGE_SIZE > */ > - sg_kunmap_atomic(bounce_addr); > + kunmap_atomic((void *)bounce_addr); > } > } > > - sg_kunmap_atomic(dest_addr - orig_sgl[i].offset); > + kunmap_atomic((void *)(dest_addr - cur_dest_sgl->offset)); > + cur_dest_sgl = sg_next(cur_dest_sgl); > } > > local_irq_restore(flags); > @@ -727,48 +727,61 @@ static unsigned int copy_to_bounce_buffer(struct > scatterlist *orig_sgl, > unsigned long bounce_addr = 0; > unsigned long src_addr = 0; > unsigned long flags; > + struct scatterlist *cur_src_sgl; > + struct scatterlist *cur_dest_sgl; > > local_irq_save(flags); > > + cur_src_sgl = orig_sgl; > + cur_dest_sgl = bounce_sgl; > + > for (i = 0; i < orig_sgl_count; i++) { > - src_addr = sg_kmap_atomic(orig_sgl,i) + orig_sgl[i].offset; > + src_addr = (unsigned long) > + kmap_atomic(sg_page(cur_src_sgl)) + > + cur_src_sgl->offset; > src = src_addr; > - srclen = orig_sgl[i].length; > + srclen = cur_src_sgl->length; > > if (bounce_addr == 0) > - bounce_addr = sg_kmap_atomic(bounce_sgl,j); > + bounce_addr = (unsigned long) > + kmap_atomic(sg_page(cur_dest_sgl)); > > while (srclen) { > /* assume bounce offset always == 0 */ > - dest = bounce_addr + bounce_sgl[j].length; > - destlen = PAGE_SIZE - bounce_sgl[j].length; > + dest = bounce_addr + cur_dest_sgl->length; > + destlen = PAGE_SIZE - cur_dest_sgl->length; > > copylen = min(srclen, destlen); > memcpy((void *)dest, (void *)src, copylen); > > total_copied += copylen; > - bounce_sgl[j].length += copylen; > + cur_dest_sgl->length += copylen; > srclen -= copylen; > src += copylen; > > - if (bounce_sgl[j].length == PAGE_SIZE) { > + if (cur_dest_sgl->length == PAGE_SIZE) { > /* full..move to next entry */ > - sg_kunmap_atomic(bounce_addr); > + kunmap_atomic((void *)bounce_addr); > bounce_addr = 0; > j++; > } > > /* if we need to use another bounce buffer */ > - if (srclen && bounce_addr == 0) > - bounce_addr = sg_kmap_atomic(bounce_sgl, > j); > + if (srclen && bounce_addr == 0) { > + cur_dest_sgl = sg_next(cur_dest_sgl); > + bounce_addr = (unsigned long) > + kmap_atomic( > + sg_page(cur_dest_sgl)); > + } > > } > > - sg_kunmap_atomic(src_addr - orig_sgl[i].offset); > + kunmap_atomic((void *)(src_addr - cur_src_sgl->offset)); > + cur_src_sgl = sg_next(cur_src_sgl); > } > > if (bounce_addr) > - sg_kunmap_atomic(bounce_addr); > + kunmap_atomic((void *)bounce_addr); > > local_irq_restore(flags); > > @@ -1536,6 +1549,7 @@ static int storvsc_queuecommand(struct Scsi_Host > *host, struct scsi_cmnd *scmnd) > struct scatterlist *sgl; > unsigned int sg_count = 0; > struct vmscsi_request *vm_srb; > + struct scatterlist *cur_sgl; > > if (vmstor_current_major <= VMSTOR_WIN8_MAJOR) { > /* > @@ -1617,10 +1631,12 @@ static int storvsc_queuecommand(struct > Scsi_Host *host, struct scsi_cmnd *scmnd) > } > > cmd_request->data_buffer.offset = sgl[0].offset; > - > - for (i = 0; i < sg_count; i++) > + cur_sgl = sgl; > + for (i = 0; i < sg_count; i++) { > cmd_request->data_buffer.pfn_array[i] = > - page_to_pfn(sg_page((&sgl[i]))); > + page_to_pfn(sg_page((cur_sgl))); > + cur_sgl = sg_next(cur_sgl); > + } > > } else if (scsi_sglist(scmnd)) { > cmd_request->data_buffer.offset = > -- > 1.7.4.1 > > _______________________________________________ > devel mailing list > devel@xxxxxxxxxxxxxxxxxxxxxx > http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
