/* * Copyright (c) 2007, 2008, 2009 QLogic Corporation. All rights reserved. * * This software is available to you under a choice of one of two * licenses. You may choose to be licensed under the terms of the GNU * General Public License (GPL) Version 2, available from the file * COPYING in the main directory of this source tree, or the * OpenIB.org BSD license below: * * Redistribution and use in source and binary forms, with or * without modification, are permitted provided that the following * conditions are met: * * - Redistributions of source code must retain the above * copyright notice, this list of conditions and the following * disclaimer. * * - Redistributions in binary form must reproduce the above * copyright notice, this list of conditions and the following * disclaimer in the documentation and/or other materials * provided with the distribution. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE * SOFTWARE. */ #include <linux/mm.h> #include <linux/types.h> #include <linux/device.h> #include <linux/dmapool.h> #include <linux/slab.h> #include <linux/list.h> #include <linux/highmem.h> #include <linux/io.h> #include <linux/uio.h> #include <linux/rbtree.h> #include <linux/spinlock.h> #include <linux/delay.h> #include "qib.h" #include "qib_user_sdma.h" /* minimum size of header */ #define QIB_USER_SDMA_MIN_HEADER_LENGTH 64 /* expected size of headers (for dma_pool) */ #define QIB_USER_SDMA_EXP_HEADER_LENGTH 64 /* attempt to drain the queue for 5secs */ #define QIB_USER_SDMA_DRAIN_TIMEOUT 500 struct qib_user_sdma_pkt { u8 naddr; /* dimension of addr (1..3) ... */ u32 counter; /* sdma pkts queued counter for this entry */ u64 added; /* global descq number of entries */ struct { u32 offset; /* offset for kvaddr, addr */ u32 length; /* length in page */ u8 put_page; /* should we put_page? */ u8 dma_mapped; /* is page dma_mapped? */ struct page *page; /* may be NULL (coherent mem) */ void *kvaddr; /* FIXME: only for pio hack */ dma_addr_t addr; } addr[4]; /* max pages, any more and we coalesce */ struct list_head list; /* list element */ }; struct qib_user_sdma_queue { /* * pkts sent to dma engine are queued on this * list head. the type of the elements of this * list are struct qib_user_sdma_pkt... */ struct list_head sent; /* headers with expected length are allocated from here... */ char header_cache_name[64]; struct dma_pool *header_cache; /* packets are allocated from the slab cache... */ char pkt_slab_name[64]; struct kmem_cache *pkt_slab; /* as packets go on the queued queue, they are counted... */ u32 counter; u32 sent_counter; /* dma page table */ struct rb_root dma_pages_root; /* protect everything above... */ struct mutex lock; }; struct qib_user_sdma_queue * qib_user_sdma_queue_create(struct device *dev, int unit, int ctxt, int sctxt) { struct qib_user_sdma_queue *pq = kmalloc(sizeof(struct qib_user_sdma_queue), GFP_KERNEL); if (!pq) goto done; pq->counter = 0; pq->sent_counter = 0; INIT_LIST_HEAD(&pq->sent); mutex_init(&pq->lock); snprintf(pq->pkt_slab_name, sizeof(pq->pkt_slab_name), "qib-user-sdma-pkts-%u-%02u.%02u", unit, ctxt, sctxt); pq->pkt_slab = kmem_cache_create(pq->pkt_slab_name, sizeof(struct qib_user_sdma_pkt), 0, 0, NULL); if (!pq->pkt_slab) goto err_kfree; snprintf(pq->header_cache_name, sizeof(pq->header_cache_name), "qib-user-sdma-headers-%u-%02u.%02u", unit, ctxt, sctxt); pq->header_cache = dma_pool_create(pq->header_cache_name, dev, QIB_USER_SDMA_EXP_HEADER_LENGTH, 4, 0); if (!pq->header_cache) goto err_slab; pq->dma_pages_root = RB_ROOT; goto done; err_slab: kmem_cache_destroy(pq->pkt_slab); err_kfree: kfree(pq); pq = NULL; done: return pq; } static void qib_user_sdma_init_frag(struct qib_user_sdma_pkt *pkt, int i, size_t offset, size_t len, int put_page, int dma_mapped, struct page *page, void *kvaddr, dma_addr_t dma_addr) { pkt->addr[i].offset = offset; pkt->addr[i].length = len; pkt->addr[i].put_page = put_page; pkt->addr[i].dma_mapped = dma_mapped; pkt->addr[i].page = page; pkt->addr[i].kvaddr = kvaddr; pkt->addr[i].addr = dma_addr; } static void qib_user_sdma_init_header(struct qib_user_sdma_pkt *pkt, u32 counter, size_t offset, size_t len, int dma_mapped, struct page *page, void *kvaddr, dma_addr_t dma_addr) { pkt->naddr = 1; pkt->counter = counter; qib_user_sdma_init_frag(pkt, 0, offset, len, 0, dma_mapped, page, kvaddr, dma_addr); } /* we've too many pages in the iovec, coalesce to a single page */ static int qib_user_sdma_coalesce(const struct qib_devdata *dd, struct qib_user_sdma_pkt *pkt, const struct iovec *iov, unsigned long niov) { int ret = 0; struct page *page = alloc_page(GFP_KERNEL); void *mpage_save; char *mpage; int i; int len = 0; dma_addr_t dma_addr; if (!page) { ret = -ENOMEM; goto done; } mpage = kmap(page); mpage_save = mpage; for (i = 0; i < niov; i++) { int cfur; cfur = copy_from_user(mpage, iov[i].iov_base, iov[i].iov_len); if (cfur) { ret = -EFAULT; goto free_unmap; } mpage += iov[i].iov_len; len += iov[i].iov_len; } dma_addr = dma_map_page(&dd->pcidev->dev, page, 0, len, DMA_TO_DEVICE); if (dma_mapping_error(&dd->pcidev->dev, dma_addr)) { ret = -ENOMEM; goto free_unmap; } qib_user_sdma_init_frag(pkt, 1, 0, len, 0, 1, page, mpage_save, dma_addr); pkt->naddr = 2; goto done; free_unmap: kunmap(page); __free_page(page); done: return ret; } /* * How many pages in this iovec element? */ static int qib_user_sdma_num_pages(const struct iovec *iov) { const unsigned long addr = (unsigned long) iov->iov_base; const unsigned long len = iov->iov_len; const unsigned long spage = addr & PAGE_MASK; const unsigned long epage = (addr + len - 1) & PAGE_MASK; return 1 + ((epage - spage) >> PAGE_SHIFT); } /* * Truncate length to page boundary. */ static int qib_user_sdma_page_length(unsigned long addr, unsigned long len) { const unsigned long offset = addr & ~PAGE_MASK; return ((offset + len) > PAGE_SIZE) ? (PAGE_SIZE - offset) : len; } static void qib_user_sdma_free_pkt_frag(struct device *dev, struct qib_user_sdma_queue *pq, struct qib_user_sdma_pkt *pkt, int frag) { const int i = frag; if (pkt->addr[i].page) { if (pkt->addr[i].dma_mapped) dma_unmap_page(dev, pkt->addr[i].addr, pkt->addr[i].length, DMA_TO_DEVICE); if (pkt->addr[i].kvaddr) kunmap(pkt->addr[i].page); if (pkt->addr[i].put_page) put_page(pkt->addr[i].page); else __free_page(pkt->addr[i].page); } else if (pkt->addr[i].kvaddr) /* free coherent mem from cache... */ dma_pool_free(pq->header_cache, pkt->addr[i].kvaddr, pkt->addr[i].addr); } /* return number of pages pinned... */ static int qib_user_sdma_pin_pages(const struct qib_devdata *dd, struct qib_user_sdma_pkt *pkt, unsigned long addr, int tlen, int npages) { struct page *pages[2]; int j; int ret; ret = get_user_pages(current, current->mm, addr, npages, 0, 1, pages, NULL); if (ret != npages) { int i; for (i = 0; i < ret; i++) put_page(pages[i]); ret = -ENOMEM; goto done; } for (j = 0; j < npages; j++) { /* map the pages... */ const int flen = qib_user_sdma_page_length(addr, tlen); dma_addr_t dma_addr = dma_map_page(&dd->pcidev->dev, pages[j], 0, flen, DMA_TO_DEVICE); unsigned long fofs = addr & ~PAGE_MASK; if (dma_mapping_error(&dd->pcidev->dev, dma_addr)) { ret = -ENOMEM; goto done; } qib_user_sdma_init_frag(pkt, pkt->naddr, fofs, flen, 1, 1, pages[j], kmap(pages[j]), dma_addr); pkt->naddr++; addr += flen; tlen -= flen; } done: return ret; } static int qib_user_sdma_pin_pkt(const struct qib_devdata *dd, struct qib_user_sdma_queue *pq, struct qib_user_sdma_pkt *pkt, const struct iovec *iov, unsigned long niov) { int ret = 0; unsigned long idx; for (idx = 0; idx < niov; idx++) { const int npages = qib_user_sdma_num_pages(iov + idx); const unsigned long addr = (unsigned long) iov[idx].iov_base; ret = qib_user_sdma_pin_pages(dd, pkt, addr, iov[idx].iov_len, npages); if (ret < 0) goto free_pkt; } goto done; free_pkt: for (idx = 0; idx < pkt->naddr; idx++) qib_user_sdma_free_pkt_frag(&dd->pcidev->dev, pq, pkt, idx); done: return ret; } static int qib_user_sdma_init_payload(const struct qib_devdata *dd, struct qib_user_sdma_queue *pq, struct qib_user_sdma_pkt *pkt, const struct iovec *iov, unsigned long niov, int npages) { int ret = 0; if (npages >= ARRAY_SIZE(pkt->addr)) ret = qib_user_sdma_coalesce(dd, pkt, iov, niov); else ret = qib_user_sdma_pin_pkt(dd, pq, pkt, iov, niov); return ret; } /* free a packet list -- return counter value of last packet */ static void qib_user_sdma_free_pkt_list(struct device *dev, struct qib_user_sdma_queue *pq, struct list_head *list) { struct qib_user_sdma_pkt *pkt, *pkt_next; list_for_each_entry_safe(pkt, pkt_next, list, list) { int i; for (i = 0; i < pkt->naddr; i++) qib_user_sdma_free_pkt_frag(dev, pq, pkt, i); kmem_cache_free(pq->pkt_slab, pkt); } INIT_LIST_HEAD(list); } /* * copy headers, coalesce etc -- pq->lock must be held * * we queue all the packets to list, returning the * number of bytes total. list must be empty initially, * as, if there is an error we clean it... */ static int qib_user_sdma_queue_pkts(const struct qib_devdata *dd, struct qib_user_sdma_queue *pq, struct list_head *list, const struct iovec *iov, unsigned long niov, int maxpkts) { unsigned long idx = 0; int ret = 0; int npkts = 0; struct page *page = NULL; __le32 *pbc; dma_addr_t dma_addr; struct qib_user_sdma_pkt *pkt = NULL; size_t len; size_t nw; u32 counter = pq->counter; int dma_mapped = 0; while (idx < niov && npkts < maxpkts) { const unsigned long addr = (unsigned long) iov[idx].iov_base; const unsigned long idx_save = idx; unsigned pktnw; unsigned pktnwc; int nfrags = 0; int npages = 0; int cfur; dma_mapped = 0; len = iov[idx].iov_len; nw = len >> 2; page = NULL; pkt = kmem_cache_alloc(pq->pkt_slab, GFP_KERNEL); if (!pkt) { ret = -ENOMEM; goto free_list; } if (len < QIB_USER_SDMA_MIN_HEADER_LENGTH || len > PAGE_SIZE || len & 3 || addr & 3) { ret = -EINVAL; goto free_pkt; } if (len == QIB_USER_SDMA_EXP_HEADER_LENGTH) pbc = dma_pool_alloc(pq->header_cache, GFP_KERNEL, &dma_addr); else pbc = NULL; if (!pbc) { page = alloc_page(GFP_KERNEL); if (!page) { ret = -ENOMEM; goto free_pkt; } pbc = kmap(page); } cfur = copy_from_user(pbc, iov[idx].iov_base, len); if (cfur) { ret = -EFAULT; goto free_pbc; } /* * This assignment is a bit strange. it's because the * the pbc counts the number of 32 bit words in the full * packet _except_ the first word of the pbc itself... */ pktnwc = nw - 1; /* * pktnw computation yields the number of 32 bit words * that the caller has indicated in the PBC. note that * this is one less than the total number of words that * goes to the send DMA engine as the first 32 bit word * of the PBC itself is not counted. Armed with this count, * we can verify that the packet is consistent with the * iovec lengths. */ pktnw = le32_to_cpu(*pbc) & QIB_PBC_LENGTH_MASK; if (pktnw < pktnwc || pktnw > pktnwc + (PAGE_SIZE >> 2)) { ret = -EINVAL; goto free_pbc; } idx++; while (pktnwc < pktnw && idx < niov) { const size_t slen = iov[idx].iov_len; const unsigned long faddr = (unsigned long) iov[idx].iov_base; if (slen & 3 || faddr & 3 || !slen || slen > PAGE_SIZE) { ret = -EINVAL; goto free_pbc; } npages++; if ((faddr & PAGE_MASK) != ((faddr + slen - 1) & PAGE_MASK)) npages++; pktnwc += slen >> 2; idx++; nfrags++; } if (pktnwc != pktnw) { ret = -EINVAL; goto free_pbc; } if (page) { dma_addr = dma_map_page(&dd->pcidev->dev, page, 0, len, DMA_TO_DEVICE); if (dma_mapping_error(&dd->pcidev->dev, dma_addr)) { ret = -ENOMEM; goto free_pbc; } dma_mapped = 1; } qib_user_sdma_init_header(pkt, counter, 0, len, dma_mapped, page, pbc, dma_addr); if (nfrags) { ret = qib_user_sdma_init_payload(dd, pq, pkt, iov + idx_save + 1, nfrags, npages); if (ret < 0) goto free_pbc_dma; } counter++; npkts++; list_add_tail(&pkt->list, list); } ret = idx; goto done; free_pbc_dma: if (dma_mapped) dma_unmap_page(&dd->pcidev->dev, dma_addr, len, DMA_TO_DEVICE); free_pbc: if (page) { kunmap(page); __free_page(page); } else dma_pool_free(pq->header_cache, pbc, dma_addr); free_pkt: kmem_cache_free(pq->pkt_slab, pkt); free_list: qib_user_sdma_free_pkt_list(&dd->pcidev->dev, pq, list); done: return ret; } static void qib_user_sdma_set_complete_counter(struct qib_user_sdma_queue *pq, u32 c) { pq->sent_counter = c; } /* try to clean out queue -- needs pq->lock */ static int qib_user_sdma_queue_clean(struct qib_pportdata *ppd, struct qib_user_sdma_queue *pq) { struct qib_devdata *dd = ppd->dd; struct list_head free_list; struct qib_user_sdma_pkt *pkt; struct qib_user_sdma_pkt *pkt_prev; int ret = 0; INIT_LIST_HEAD(&free_list); list_for_each_entry_safe(pkt, pkt_prev, &pq->sent, list) { s64 descd = ppd->sdma_descq_removed - pkt->added; if (descd < 0) break; list_move_tail(&pkt->list, &free_list); /* one more packet cleaned */ ret++; } if (!list_empty(&free_list)) { u32 counter; pkt = list_entry(free_list.prev, struct qib_user_sdma_pkt, list); counter = pkt->counter; qib_user_sdma_free_pkt_list(&dd->pcidev->dev, pq, &free_list); qib_user_sdma_set_complete_counter(pq, counter); } return ret; } void qib_user_sdma_queue_destroy(struct qib_user_sdma_queue *pq) { if (!pq) return; kmem_cache_destroy(pq->pkt_slab); dma_pool_destroy(pq->header_cache); kfree(pq); } /* clean descriptor queue, returns > 0 if some elements cleaned */ static int qib_user_sdma_hwqueue_clean(struct qib_pportdata *ppd) { int ret; unsigned long flags; spin_lock_irqsave(&ppd->sdma_lock, flags); ret = qib_sdma_make_progress(ppd); spin_unlock_irqrestore(&ppd->sdma_lock, flags); return ret; } /* we're in close, drain packets so that we can cleanup successfully... */ void qib_user_sdma_queue_drain(struct qib_pportdata *ppd, struct qib_user_sdma_queue *pq) { struct qib_devdata *dd = ppd->dd; int i; if (!pq) return; for (i = 0; i < QIB_USER_SDMA_DRAIN_TIMEOUT; i++) { mutex_lock(&pq->lock); if (list_empty(&pq->sent)) { mutex_unlock(&pq->lock); break; } qib_user_sdma_hwqueue_clean(ppd); qib_user_sdma_queue_clean(ppd, pq); mutex_unlock(&pq->lock); msleep(10); } if (!list_empty(&pq->sent)) { struct list_head free_list; qib_dev_err(dd, "user sdma lists not empty: forcing!\n"); INIT_LIST_HEAD(&free_list); mutex_lock(&pq->lock); list_splice_init(&pq->sent, &free_list); qib_user_sdma_free_pkt_list(&dd->pcidev->dev, pq, &free_list); mutex_unlock(&pq->lock); } } static inline __le64 qib_sdma_make_desc0(struct qib_pportdata *ppd, u64 addr, u64 dwlen, u64 dwoffset) { u8 tmpgen; tmpgen = ppd->sdma_generation; return cpu_to_le64(/* SDmaPhyAddr[31:0] */ ((addr & 0xfffffffcULL) << 32) | /* SDmaGeneration[1:0] */ ((tmpgen & 3ULL) << 30) | /* SDmaDwordCount[10:0] */ ((dwlen & 0x7ffULL) << 16) | /* SDmaBufOffset[12:2] */ (dwoffset & 0x7ffULL)); } static inline __le64 qib_sdma_make_first_desc0(__le64 descq) { return descq | cpu_to_le64(1ULL << 12); } static inline __le64 qib_sdma_make_last_desc0(__le64 descq) { /* last */ /* dma head */ return descq | cpu_to_le64(1ULL << 11 | 1ULL << 13); } static inline __le64 qib_sdma_make_desc1(u64 addr) { /* SDmaPhyAddr[47:32] */ return cpu_to_le64(addr >> 32); } static void qib_user_sdma_send_frag(struct qib_pportdata *ppd, struct qib_user_sdma_pkt *pkt, int idx, unsigned ofs, u16 tail) { const u64 addr = (u64) pkt->addr[idx].addr + (u64) pkt->addr[idx].offset; const u64 dwlen = (u64) pkt->addr[idx].length / 4; __le64 *descqp; __le64 descq0; descqp = &ppd->sdma_descq[tail].qw[0]; descq0 = qib_sdma_make_desc0(ppd, addr, dwlen, ofs); if (idx == 0) descq0 = qib_sdma_make_first_desc0(descq0); if (idx == pkt->naddr - 1) descq0 = qib_sdma_make_last_desc0(descq0); descqp[0] = descq0; descqp[1] = qib_sdma_make_desc1(addr); } /* pq->lock must be held, get packets on the wire... */ static int qib_user_sdma_push_pkts(struct qib_pportdata *ppd, struct qib_user_sdma_queue *pq, struct list_head *pktlist) { struct qib_devdata *dd = ppd->dd; int ret = 0; unsigned long flags; u16 tail; u8 generation; u64 descq_added; if (list_empty(pktlist)) return 0; if (unlikely(!(ppd->lflags & QIBL_LINKACTIVE))) return -ECOMM; spin_lock_irqsave(&ppd->sdma_lock, flags); /* keep a copy for restoring purposes in case of problems */ generation = ppd->sdma_generation; descq_added = ppd->sdma_descq_added; if (unlikely(!__qib_sdma_running(ppd))) { ret = -ECOMM; goto unlock; } tail = ppd->sdma_descq_tail; while (!list_empty(pktlist)) { struct qib_user_sdma_pkt *pkt = list_entry(pktlist->next, struct qib_user_sdma_pkt, list); int i; unsigned ofs = 0; u16 dtail = tail; if (pkt->naddr > qib_sdma_descq_freecnt(ppd)) goto unlock_check_tail; for (i = 0; i < pkt->naddr; i++) { qib_user_sdma_send_frag(ppd, pkt, i, ofs, tail); ofs += pkt->addr[i].length >> 2; if (++tail == ppd->sdma_descq_cnt) { tail = 0; ++ppd->sdma_generation; } } if ((ofs << 2) > ppd->ibmaxlen) { ret = -EMSGSIZE; goto unlock; } /* * If the packet is >= 2KB mtu equivalent, we have to use * the large buffers, and have to mark each descriptor as * part of a large buffer packet. */ if (ofs > dd->piosize2kmax_dwords) { for (i = 0; i < pkt->naddr; i++) { ppd->sdma_descq[dtail].qw[0] |= cpu_to_le64(1ULL << 14); if (++dtail == ppd->sdma_descq_cnt) dtail = 0; } } ppd->sdma_descq_added += pkt->naddr; pkt->added = ppd->sdma_descq_added; list_move_tail(&pkt->list, &pq->sent); ret++; } unlock_check_tail: /* advance the tail on the chip if necessary */ if (ppd->sdma_descq_tail != tail) dd->f_sdma_update_tail(ppd, tail); unlock: if (unlikely(ret < 0)) { ppd->sdma_generation = generation; ppd->sdma_descq_added = descq_added; } spin_unlock_irqrestore(&ppd->sdma_lock, flags); return ret; } int qib_user_sdma_writev(struct qib_ctxtdata *rcd, struct qib_user_sdma_queue *pq, const struct iovec *iov, unsigned long dim) { struct qib_devdata *dd = rcd->dd; struct qib_pportdata *ppd = rcd->ppd; int ret = 0; struct list_head list; int npkts = 0; INIT_LIST_HEAD(&list); mutex_lock(&pq->lock); /* why not -ECOMM like qib_user_sdma_push_pkts() below? */ if (!qib_sdma_running(ppd)) goto done_unlock; if (ppd->sdma_descq_added != ppd->sdma_descq_removed) { qib_user_sdma_hwqueue_clean(ppd); qib_user_sdma_queue_clean(ppd, pq); } while (dim) { const int mxp = 8; down_write(¤t->mm->mmap_sem); ret = qib_user_sdma_queue_pkts(dd, pq, &list, iov, dim, mxp); up_write(¤t->mm->mmap_sem); if (ret <= 0) goto done_unlock; else { dim -= ret; iov += ret; } /* force packets onto the sdma hw queue... */ if (!list_empty(&list)) { /* * Lazily clean hw queue. the 4 is a guess of about * how many sdma descriptors a packet will take (it * doesn't have to be perfect). */ if (qib_sdma_descq_freecnt(ppd) < ret * 4) { qib_user_sdma_hwqueue_clean(ppd); qib_user_sdma_queue_clean(ppd, pq); } ret = qib_user_sdma_push_pkts(ppd, pq, &list); if (ret < 0) goto done_unlock; else { npkts += ret; pq->counter += ret; if (!list_empty(&list)) goto done_unlock; } } } done_unlock: if (!list_empty(&list)) qib_user_sdma_free_pkt_list(&dd->pcidev->dev, pq, &list); mutex_unlock(&pq->lock); return (ret < 0) ? ret : npkts; } int qib_user_sdma_make_progress(struct qib_pportdata *ppd, struct qib_user_sdma_queue *pq) { int ret = 0; mutex_lock(&pq->lock); qib_user_sdma_hwqueue_clean(ppd); ret = qib_user_sdma_queue_clean(ppd, pq); mutex_unlock(&pq->lock); return ret; } u32 qib_user_sdma_complete_counter(const struct qib_user_sdma_queue *pq) { return pq ? pq->sent_counter : 0; } u32 qib_user_sdma_inflight_counter(struct qib_user_sdma_queue *pq) { return pq ? pq->counter : 0; }