diff options
Diffstat (limited to 'drivers/s390/cio/vfio_ccw_cp.c')
-rw-r--r-- | drivers/s390/cio/vfio_ccw_cp.c | 205 |
1 files changed, 124 insertions, 81 deletions
diff --git a/drivers/s390/cio/vfio_ccw_cp.c b/drivers/s390/cio/vfio_ccw_cp.c index 0c2be9421ab7..7b02e97f4b29 100644 --- a/drivers/s390/cio/vfio_ccw_cp.c +++ b/drivers/s390/cio/vfio_ccw_cp.c @@ -11,6 +11,7 @@ #include <linux/ratelimit.h> #include <linux/mm.h> #include <linux/slab.h> +#include <linux/highmem.h> #include <linux/iommu.h> #include <linux/vfio.h> #include <asm/idals.h> @@ -18,13 +19,11 @@ #include "vfio_ccw_cp.h" #include "vfio_ccw_private.h" -struct pfn_array { - /* Starting guest physical I/O address. */ - unsigned long pa_iova; - /* Array that stores PFNs of the pages need to pin. */ - unsigned long *pa_iova_pfn; - /* Array that receives PFNs of the pages pinned. */ - unsigned long *pa_pfn; +struct page_array { + /* Array that stores pages need to pin. */ + dma_addr_t *pa_iova; + /* Array that receives the pinned pages. */ + struct page **pa_page; /* Number of pages pinned from @pa_iova. */ int pa_nr; }; @@ -37,116 +36,158 @@ struct ccwchain { /* Count of the valid ccws in chain. */ int ch_len; /* Pinned PAGEs for the original data. */ - struct pfn_array *ch_pa; + struct page_array *ch_pa; }; /* - * pfn_array_alloc() - alloc memory for PFNs - * @pa: pfn_array on which to perform the operation + * page_array_alloc() - alloc memory for page array + * @pa: page_array on which to perform the operation * @iova: target guest physical address * @len: number of bytes that should be pinned from @iova * - * Attempt to allocate memory for PFNs. + * Attempt to allocate memory for page array. * - * Usage of pfn_array: - * We expect (pa_nr == 0) and (pa_iova_pfn == NULL), any field in + * Usage of page_array: + * We expect (pa_nr == 0) and (pa_iova == NULL), any field in * this structure will be filled in by this function. * * Returns: - * 0 if PFNs are allocated - * -EINVAL if pa->pa_nr is not initially zero, or pa->pa_iova_pfn is not NULL + * 0 if page array is allocated + * -EINVAL if pa->pa_nr is not initially zero, or pa->pa_iova is not NULL * -ENOMEM if alloc failed */ -static int pfn_array_alloc(struct pfn_array *pa, u64 iova, unsigned int len) +static int page_array_alloc(struct page_array *pa, u64 iova, unsigned int len) { int i; - if (pa->pa_nr || pa->pa_iova_pfn) + if (pa->pa_nr || pa->pa_iova) return -EINVAL; - pa->pa_iova = iova; - pa->pa_nr = ((iova & ~PAGE_MASK) + len + (PAGE_SIZE - 1)) >> PAGE_SHIFT; if (!pa->pa_nr) return -EINVAL; - pa->pa_iova_pfn = kcalloc(pa->pa_nr, - sizeof(*pa->pa_iova_pfn) + - sizeof(*pa->pa_pfn), - GFP_KERNEL); - if (unlikely(!pa->pa_iova_pfn)) { + pa->pa_iova = kcalloc(pa->pa_nr, + sizeof(*pa->pa_iova) + sizeof(*pa->pa_page), + GFP_KERNEL); + if (unlikely(!pa->pa_iova)) { pa->pa_nr = 0; return -ENOMEM; } - pa->pa_pfn = pa->pa_iova_pfn + pa->pa_nr; + pa->pa_page = (struct page **)&pa->pa_iova[pa->pa_nr]; - pa->pa_iova_pfn[0] = pa->pa_iova >> PAGE_SHIFT; - pa->pa_pfn[0] = -1ULL; + pa->pa_iova[0] = iova; + pa->pa_page[0] = NULL; for (i = 1; i < pa->pa_nr; i++) { - pa->pa_iova_pfn[i] = pa->pa_iova_pfn[i - 1] + 1; - pa->pa_pfn[i] = -1ULL; + pa->pa_iova[i] = pa->pa_iova[i - 1] + PAGE_SIZE; + pa->pa_page[i] = NULL; } return 0; } /* - * pfn_array_pin() - Pin user pages in memory - * @pa: pfn_array on which to perform the operation + * page_array_unpin() - Unpin user pages in memory + * @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 + * + * 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) +{ + int unpinned = 0, npage = 1; + + while (unpinned < pa_nr) { + dma_addr_t *first = &pa->pa_iova[unpinned]; + dma_addr_t *last = &first[npage]; + + if (unpinned + npage < pa_nr && + *first + npage * PAGE_SIZE == *last) { + npage++; + continue; + } + + vfio_unpin_pages(vdev, *first, npage); + unpinned += npage; + npage = 1; + } + + pa->pa_nr = 0; +} + +/* + * page_array_pin() - Pin user pages in memory + * @pa: page_array on which to perform the operation * @mdev: the mediated device to perform pin operations * * 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. */ -static int pfn_array_pin(struct pfn_array *pa, struct vfio_device *vdev) +static int page_array_pin(struct page_array *pa, struct vfio_device *vdev) { + int pinned = 0, npage = 1; int ret = 0; - ret = vfio_pin_pages(vdev, pa->pa_iova_pfn, pa->pa_nr, - IOMMU_READ | IOMMU_WRITE, pa->pa_pfn); + while (pinned < pa->pa_nr) { + dma_addr_t *first = &pa->pa_iova[pinned]; + dma_addr_t *last = &first[npage]; - if (ret < 0) { - goto err_out; - } else if (ret > 0 && ret != pa->pa_nr) { - vfio_unpin_pages(vdev, pa->pa_iova_pfn, ret); - ret = -EINVAL; - goto err_out; + if (pinned + npage < pa->pa_nr && + *first + npage * PAGE_SIZE == *last) { + npage++; + continue; + } + + ret = vfio_pin_pages(vdev, *first, npage, + IOMMU_READ | IOMMU_WRITE, + &pa->pa_page[pinned]); + if (ret < 0) { + goto err_out; + } else if (ret > 0 && ret != npage) { + pinned += ret; + ret = -EINVAL; + goto err_out; + } + pinned += npage; + npage = 1; } return ret; err_out: - pa->pa_nr = 0; - + page_array_unpin(pa, vdev, pinned); return ret; } /* Unpin the pages before releasing the memory. */ -static void pfn_array_unpin_free(struct pfn_array *pa, struct vfio_device *vdev) +static void page_array_unpin_free(struct page_array *pa, struct vfio_device *vdev) { - /* Only unpin if any pages were pinned to begin with */ - if (pa->pa_nr) - vfio_unpin_pages(vdev, pa->pa_iova_pfn, pa->pa_nr); - pa->pa_nr = 0; - kfree(pa->pa_iova_pfn); + page_array_unpin(pa, vdev, pa->pa_nr); + kfree(pa->pa_iova); } -static bool pfn_array_iova_pinned(struct pfn_array *pa, unsigned long iova) +static bool page_array_iova_pinned(struct page_array *pa, u64 iova, u64 length) { - unsigned long iova_pfn = iova >> PAGE_SHIFT; + u64 iova_pfn_start = iova >> PAGE_SHIFT; + u64 iova_pfn_end = (iova + length - 1) >> PAGE_SHIFT; + u64 pfn; int i; - for (i = 0; i < pa->pa_nr; i++) - if (pa->pa_iova_pfn[i] == iova_pfn) + for (i = 0; i < pa->pa_nr; i++) { + pfn = pa->pa_iova[i] >> PAGE_SHIFT; + if (pfn >= iova_pfn_start && pfn <= iova_pfn_end) return true; + } return false; } -/* Create the list of IDAL words for a pfn_array. */ -static inline void pfn_array_idal_create_words( - struct pfn_array *pa, - unsigned long *idaws) +/* Create the list of IDAL words for a page_array. */ +static inline void page_array_idal_create_words(struct page_array *pa, + unsigned long *idaws) { int i; @@ -159,10 +200,10 @@ static inline void pfn_array_idal_create_words( */ for (i = 0; i < pa->pa_nr; i++) - idaws[i] = pa->pa_pfn[i] << PAGE_SHIFT; + idaws[i] = page_to_phys(pa->pa_page[i]); /* Adjust the first IDAW, since it may not start on a page boundary */ - idaws[0] += pa->pa_iova & (PAGE_SIZE - 1); + idaws[0] += pa->pa_iova[0] & (PAGE_SIZE - 1); } static void convert_ccw0_to_ccw1(struct ccw1 *source, unsigned long len) @@ -194,24 +235,24 @@ static void convert_ccw0_to_ccw1(struct ccw1 *source, unsigned long len) static long copy_from_iova(struct vfio_device *vdev, void *to, u64 iova, unsigned long n) { - struct pfn_array pa = {0}; - u64 from; + struct page_array pa = {0}; int i, ret; unsigned long l, m; - ret = pfn_array_alloc(&pa, iova, n); + ret = page_array_alloc(&pa, iova, n); if (ret < 0) return ret; - ret = pfn_array_pin(&pa, vdev); + ret = page_array_pin(&pa, vdev); if (ret < 0) { - pfn_array_unpin_free(&pa, vdev); + page_array_unpin_free(&pa, vdev); return ret; } l = n; for (i = 0; i < pa.pa_nr; i++) { - from = pa.pa_pfn[i] << PAGE_SHIFT; + void *from = kmap_local_page(pa.pa_page[i]); + m = PAGE_SIZE; if (i == 0) { from += iova & (PAGE_SIZE - 1); @@ -219,14 +260,15 @@ static long copy_from_iova(struct vfio_device *vdev, void *to, u64 iova, } m = min(l, m); - memcpy(to + (n - l), (void *)from, m); + memcpy(to + (n - l), from, m); + kunmap_local(from); l -= m; if (l == 0) break; } - pfn_array_unpin_free(&pa, vdev); + page_array_unpin_free(&pa, vdev); return l; } @@ -329,7 +371,7 @@ static struct ccwchain *ccwchain_alloc(struct channel_program *cp, int len) chain->ch_ccw = (struct ccw1 *)data; data = (u8 *)(chain->ch_ccw) + sizeof(*chain->ch_ccw) * len; - chain->ch_pa = (struct pfn_array *)data; + chain->ch_pa = (struct page_array *)data; chain->ch_len = len; @@ -513,7 +555,7 @@ static int ccwchain_fetch_direct(struct ccwchain *chain, struct vfio_device *vdev = &container_of(cp, struct vfio_ccw_private, cp)->vdev; struct ccw1 *ccw; - struct pfn_array *pa; + struct page_array *pa; u64 iova; unsigned long *idaws; int ret; @@ -547,13 +589,13 @@ static int ccwchain_fetch_direct(struct ccwchain *chain, } /* - * Allocate an array of pfn's for pages to pin/translate. + * Allocate an array of pages to pin/translate. * The number of pages is actually the count of the idaws * required for the data transfer, since we only only support * 4K IDAWs today. */ pa = chain->ch_pa + idx; - ret = pfn_array_alloc(pa, iova, bytes); + ret = page_array_alloc(pa, iova, bytes); if (ret < 0) goto out_free_idaws; @@ -564,21 +606,21 @@ static int ccwchain_fetch_direct(struct ccwchain *chain, goto out_unpin; /* - * Copy guest IDAWs into pfn_array, in case the memory they + * Copy guest IDAWs into page_array, in case the memory they * occupy is not contiguous. */ for (i = 0; i < idaw_nr; i++) - pa->pa_iova_pfn[i] = idaws[i] >> PAGE_SHIFT; + pa->pa_iova[i] = idaws[i]; } else { /* - * No action is required here; the iova addresses in pfn_array - * were initialized sequentially in pfn_array_alloc() beginning + * No action is required here; the iova addresses in page_array + * were initialized sequentially in page_array_alloc() beginning * with the contents of ccw->cda. */ } if (ccw_does_data_transfer(ccw)) { - ret = pfn_array_pin(pa, vdev); + ret = page_array_pin(pa, vdev); if (ret < 0) goto out_unpin; } else { @@ -588,13 +630,13 @@ static int ccwchain_fetch_direct(struct ccwchain *chain, ccw->cda = (__u32) virt_to_phys(idaws); ccw->flags |= CCW_FLAG_IDA; - /* Populate the IDAL with pinned/translated addresses from pfn */ - pfn_array_idal_create_words(pa, idaws); + /* Populate the IDAL with pinned/translated addresses from page */ + page_array_idal_create_words(pa, idaws); return 0; out_unpin: - pfn_array_unpin_free(pa, vdev); + page_array_unpin_free(pa, vdev); out_free_idaws: kfree(idaws); out_init: @@ -700,7 +742,7 @@ 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++) { - pfn_array_unpin_free(chain->ch_pa + i, vdev); + page_array_unpin_free(chain->ch_pa + i, vdev); ccwchain_cda_free(chain, i); } ccwchain_free(chain); @@ -862,11 +904,12 @@ void cp_update_scsw(struct channel_program *cp, union scsw *scsw) * cp_iova_pinned() - check if an iova is pinned for a ccw chain. * @cp: channel_program on which to perform the operation * @iova: the iova to check + * @length: the length to check from @iova * * If the @iova is currently pinned for the ccw chain, return true; * else return false. */ -bool cp_iova_pinned(struct channel_program *cp, u64 iova) +bool cp_iova_pinned(struct channel_program *cp, u64 iova, u64 length) { struct ccwchain *chain; int i; @@ -876,7 +919,7 @@ bool cp_iova_pinned(struct channel_program *cp, u64 iova) list_for_each_entry(chain, &cp->ccwchain_list, next) { for (i = 0; i < chain->ch_len; i++) - if (pfn_array_iova_pinned(chain->ch_pa + i, iova)) + if (page_array_iova_pinned(chain->ch_pa + i, iova, length)) return true; } |