diff options
Diffstat (limited to 'drivers/s390')
| -rw-r--r-- | drivers/s390/cio/vfio_ccw_cp.c | 30 |
1 files changed, 20 insertions, 10 deletions
diff --git a/drivers/s390/cio/vfio_ccw_cp.c b/drivers/s390/cio/vfio_ccw_cp.c index a7415d440a81..1500058dbe1f 100644 --- a/drivers/s390/cio/vfio_ccw_cp.c +++ b/drivers/s390/cio/vfio_ccw_cp.c @@ -83,12 +83,13 @@ static int page_array_alloc(struct page_array *pa, unsigned int len) * @pa: page_array on which to perform the operation * @vdev: the vfio device to perform the operation * @pa_nr: number of user pages to unpin + * @unaligned: were pages unaligned on the pin request * * Only unpin if any pages were pinned to begin with, i.e. pa_nr > 0, * otherwise only clear pa->pa_nr */ static void page_array_unpin(struct page_array *pa, - struct vfio_device *vdev, int pa_nr) + struct vfio_device *vdev, int pa_nr, bool unaligned) { int unpinned = 0, npage = 1; @@ -97,7 +98,8 @@ static void page_array_unpin(struct page_array *pa, dma_addr_t *last = &first[npage]; if (unpinned + npage < pa_nr && - *first + npage * PAGE_SIZE == *last) { + *first + npage * PAGE_SIZE == *last && + !unaligned) { npage++; continue; } @@ -114,12 +116,19 @@ static void page_array_unpin(struct page_array *pa, * page_array_pin() - Pin user pages in memory * @pa: page_array on which to perform the operation * @vdev: the vfio device to perform pin operations + * @unaligned: are pages aligned to 4K boundary? * * Returns number of pages pinned upon success. * If the pin request partially succeeds, or fails completely, * all pages are left unpinned and a negative error value is returned. + * + * Requests to pin "aligned" pages can be coalesced into a single + * vfio_pin_pages request for the sake of efficiency, based on the + * expectation of 4K page requests. Unaligned requests are probably + * dealing with 2K "pages", and cannot be coalesced without + * reworking this logic to incorporate that math. */ -static int page_array_pin(struct page_array *pa, struct vfio_device *vdev) +static int page_array_pin(struct page_array *pa, struct vfio_device *vdev, bool unaligned) { int pinned = 0, npage = 1; int ret = 0; @@ -129,7 +138,8 @@ static int page_array_pin(struct page_array *pa, struct vfio_device *vdev) dma_addr_t *last = &first[npage]; if (pinned + npage < pa->pa_nr && - *first + npage * PAGE_SIZE == *last) { + *first + npage * PAGE_SIZE == *last && + !unaligned) { npage++; continue; } @@ -151,14 +161,14 @@ static int page_array_pin(struct page_array *pa, struct vfio_device *vdev) return ret; err_out: - page_array_unpin(pa, vdev, pinned); + page_array_unpin(pa, vdev, pinned, unaligned); return ret; } /* Unpin the pages before releasing the memory. */ -static void page_array_unpin_free(struct page_array *pa, struct vfio_device *vdev) +static void page_array_unpin_free(struct page_array *pa, struct vfio_device *vdev, bool unaligned) { - page_array_unpin(pa, vdev, pa->pa_nr); + page_array_unpin(pa, vdev, pa->pa_nr, unaligned); kfree(pa->pa_page); kfree(pa->pa_iova); } @@ -643,7 +653,7 @@ static int ccwchain_fetch_ccw(struct ccw1 *ccw, } if (ccw_does_data_transfer(ccw)) { - ret = page_array_pin(pa, vdev); + ret = page_array_pin(pa, vdev, idal_is_2k(cp)); if (ret < 0) goto out_unpin; } else { @@ -659,7 +669,7 @@ static int ccwchain_fetch_ccw(struct ccw1 *ccw, return 0; out_unpin: - page_array_unpin_free(pa, vdev); + page_array_unpin_free(pa, vdev, idal_is_2k(cp)); out_free_idaws: kfree(idaws); out_init: @@ -757,7 +767,7 @@ void cp_free(struct channel_program *cp) cp->initialized = false; list_for_each_entry_safe(chain, temp, &cp->ccwchain_list, next) { for (i = 0; i < chain->ch_len; i++) { - page_array_unpin_free(&chain->ch_pa[i], vdev); + page_array_unpin_free(&chain->ch_pa[i], vdev, idal_is_2k(cp)); ccwchain_cda_free(chain, i); } ccwchain_free(chain); |