From aaced9934d2231227fec4255f394eb86af818ce2 Mon Sep 17 00:00:00 2001 From: "K. Y. Srinivasan" Date: Fri, 27 Mar 2015 00:27:19 -0700 Subject: 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 Reviewed-by: Long Li Signed-off-by: James Bottomley --- drivers/scsi/storvsc_drv.c | 99 ++++++++++++++++++++++++++-------------------- 1 file changed, 57 insertions(+), 42 deletions(-) (limited to 'drivers/scsi/storvsc_drv.c') diff --git a/drivers/scsi/storvsc_drv.c b/drivers/scsi/storvsc_drv.c index f8e4dd925a9d..4156e297ea64 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 +640,38 @@ 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 +685,27 @@ 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 +726,61 @@ 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 +1548,7 @@ 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 +1630,12 @@ 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 = -- cgit v1.2.3-59-g8ed1b