diff options
Diffstat (limited to 'drivers/infiniband/hw/qib/qib_user_sdma.c')
-rw-r--r-- | drivers/infiniband/hw/qib/qib_user_sdma.c | 1475 |
1 files changed, 1475 insertions, 0 deletions
diff --git a/drivers/infiniband/hw/qib/qib_user_sdma.c b/drivers/infiniband/hw/qib/qib_user_sdma.c new file mode 100644 index 000000000..bf2f30d67 --- /dev/null +++ b/drivers/infiniband/hw/qib/qib_user_sdma.c @@ -0,0 +1,1475 @@ +/* + * 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 250 + +/* + * track how many times a process open this driver. + */ +static struct rb_root qib_user_sdma_rb_root = RB_ROOT; + +struct qib_user_sdma_rb_node { + struct rb_node node; + int refcount; + pid_t pid; +}; + +struct qib_user_sdma_pkt { + struct list_head list; /* list element */ + + u8 tiddma; /* if this is NEW tid-sdma */ + u8 largepkt; /* this is large pkt from kmalloc */ + u16 frag_size; /* frag size used by PSM */ + u16 index; /* last header index or push index */ + u16 naddr; /* dimension of addr (1..3) ... */ + u16 addrlimit; /* addr array size */ + u16 tidsmidx; /* current tidsm index */ + u16 tidsmcount; /* tidsm array item count */ + u16 payload_size; /* payload size so far for header */ + u32 bytes_togo; /* bytes for processing */ + u32 counter; /* sdma pkts queued counter for this entry */ + struct qib_tid_session_member *tidsm; /* tid session member array */ + struct qib_user_sdma_queue *pq; /* which pq this pkt belongs to */ + u64 added; /* global descq number of entries */ + + struct { + u16 offset; /* offset for kvaddr, addr */ + u16 length; /* length in page */ + u16 first_desc; /* first desc */ + u16 last_desc; /* last desc */ + u16 put_page; /* should we put_page? */ + u16 dma_mapped; /* is page dma_mapped? */ + u16 dma_length; /* for dma_unmap_page() */ + u16 padding; + 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 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; + + /* + * Because above list will be accessed by both process and + * signal handler, we need a spinlock for it. + */ + spinlock_t sent_lock ____cacheline_aligned_in_smp; + + /* 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; + /* pending packets, not sending yet */ + u32 num_pending; + /* sending packets, not complete yet */ + u32 num_sending; + /* global descq number of entry of last sending packet */ + u64 added; + + /* dma page table */ + struct rb_root dma_pages_root; + + struct qib_user_sdma_rb_node *sdma_rb_node; + + /* protect everything above... */ + struct mutex lock; +}; + +static struct qib_user_sdma_rb_node * +qib_user_sdma_rb_search(struct rb_root *root, pid_t pid) +{ + struct qib_user_sdma_rb_node *sdma_rb_node; + struct rb_node *node = root->rb_node; + + while (node) { + sdma_rb_node = rb_entry(node, struct qib_user_sdma_rb_node, + node); + if (pid < sdma_rb_node->pid) + node = node->rb_left; + else if (pid > sdma_rb_node->pid) + node = node->rb_right; + else + return sdma_rb_node; + } + return NULL; +} + +static int +qib_user_sdma_rb_insert(struct rb_root *root, struct qib_user_sdma_rb_node *new) +{ + struct rb_node **node = &(root->rb_node); + struct rb_node *parent = NULL; + struct qib_user_sdma_rb_node *got; + + while (*node) { + got = rb_entry(*node, struct qib_user_sdma_rb_node, node); + parent = *node; + if (new->pid < got->pid) + node = &((*node)->rb_left); + else if (new->pid > got->pid) + node = &((*node)->rb_right); + else + return 0; + } + + rb_link_node(&new->node, parent, node); + rb_insert_color(&new->node, root); + return 1; +} + +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); + struct qib_user_sdma_rb_node *sdma_rb_node; + + if (!pq) + goto done; + + pq->counter = 0; + pq->sent_counter = 0; + pq->num_pending = 0; + pq->num_sending = 0; + pq->added = 0; + pq->sdma_rb_node = NULL; + + INIT_LIST_HEAD(&pq->sent); + spin_lock_init(&pq->sent_lock); + 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; + + sdma_rb_node = qib_user_sdma_rb_search(&qib_user_sdma_rb_root, + current->pid); + if (sdma_rb_node) { + sdma_rb_node->refcount++; + } else { + sdma_rb_node = kmalloc(sizeof( + struct qib_user_sdma_rb_node), GFP_KERNEL); + if (!sdma_rb_node) + goto err_rb; + + sdma_rb_node->refcount = 1; + sdma_rb_node->pid = current->pid; + + qib_user_sdma_rb_insert(&qib_user_sdma_rb_root, sdma_rb_node); + } + pq->sdma_rb_node = sdma_rb_node; + + goto done; + +err_rb: + dma_pool_destroy(pq->header_cache); +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, u16 offset, u16 len, + u16 first_desc, u16 last_desc, + u16 put_page, u16 dma_mapped, + struct page *page, void *kvaddr, + dma_addr_t dma_addr, u16 dma_length) +{ + pkt->addr[i].offset = offset; + pkt->addr[i].length = len; + pkt->addr[i].first_desc = first_desc; + pkt->addr[i].last_desc = last_desc; + 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; + pkt->addr[i].dma_length = dma_length; +} + +static void *qib_user_sdma_alloc_header(struct qib_user_sdma_queue *pq, + size_t len, dma_addr_t *dma_addr) +{ + void *hdr; + + if (len == QIB_USER_SDMA_EXP_HEADER_LENGTH) + hdr = dma_pool_alloc(pq->header_cache, GFP_KERNEL, + dma_addr); + else + hdr = NULL; + + if (!hdr) { + hdr = kmalloc(len, GFP_KERNEL); + if (!hdr) + return NULL; + + *dma_addr = 0; + } + + return hdr; +} + +static int qib_user_sdma_page_to_frags(const struct qib_devdata *dd, + struct qib_user_sdma_queue *pq, + struct qib_user_sdma_pkt *pkt, + struct page *page, u16 put, + u16 offset, u16 len, void *kvaddr) +{ + __le16 *pbc16; + void *pbcvaddr; + struct qib_message_header *hdr; + u16 newlen, pbclen, lastdesc, dma_mapped; + u32 vcto; + union qib_seqnum seqnum; + dma_addr_t pbcdaddr; + dma_addr_t dma_addr = + dma_map_page(&dd->pcidev->dev, + page, offset, len, DMA_TO_DEVICE); + int ret = 0; + + if (dma_mapping_error(&dd->pcidev->dev, dma_addr)) { + /* + * dma mapping error, pkt has not managed + * this page yet, return the page here so + * the caller can ignore this page. + */ + if (put) { + unpin_user_page(page); + } else { + /* coalesce case */ + kunmap(page); + __free_page(page); + } + ret = -ENOMEM; + goto done; + } + offset = 0; + dma_mapped = 1; + + +next_fragment: + + /* + * In tid-sdma, the transfer length is restricted by + * receiver side current tid page length. + */ + if (pkt->tiddma && len > pkt->tidsm[pkt->tidsmidx].length) + newlen = pkt->tidsm[pkt->tidsmidx].length; + else + newlen = len; + + /* + * Then the transfer length is restricted by MTU. + * the last descriptor flag is determined by: + * 1. the current packet is at frag size length. + * 2. the current tid page is done if tid-sdma. + * 3. there is no more byte togo if sdma. + */ + lastdesc = 0; + if ((pkt->payload_size + newlen) >= pkt->frag_size) { + newlen = pkt->frag_size - pkt->payload_size; + lastdesc = 1; + } else if (pkt->tiddma) { + if (newlen == pkt->tidsm[pkt->tidsmidx].length) + lastdesc = 1; + } else { + if (newlen == pkt->bytes_togo) + lastdesc = 1; + } + + /* fill the next fragment in this page */ + qib_user_sdma_init_frag(pkt, pkt->naddr, /* index */ + offset, newlen, /* offset, len */ + 0, lastdesc, /* first last desc */ + put, dma_mapped, /* put page, dma mapped */ + page, kvaddr, /* struct page, virt addr */ + dma_addr, len); /* dma addr, dma length */ + pkt->bytes_togo -= newlen; + pkt->payload_size += newlen; + pkt->naddr++; + if (pkt->naddr == pkt->addrlimit) { + ret = -EFAULT; + goto done; + } + + /* If there is no more byte togo. (lastdesc==1) */ + if (pkt->bytes_togo == 0) { + /* The packet is done, header is not dma mapped yet. + * it should be from kmalloc */ + if (!pkt->addr[pkt->index].addr) { + pkt->addr[pkt->index].addr = + dma_map_single(&dd->pcidev->dev, + pkt->addr[pkt->index].kvaddr, + pkt->addr[pkt->index].dma_length, + DMA_TO_DEVICE); + if (dma_mapping_error(&dd->pcidev->dev, + pkt->addr[pkt->index].addr)) { + ret = -ENOMEM; + goto done; + } + pkt->addr[pkt->index].dma_mapped = 1; + } + + goto done; + } + + /* If tid-sdma, advance tid info. */ + if (pkt->tiddma) { + pkt->tidsm[pkt->tidsmidx].length -= newlen; + if (pkt->tidsm[pkt->tidsmidx].length) { + pkt->tidsm[pkt->tidsmidx].offset += newlen; + } else { + pkt->tidsmidx++; + if (pkt->tidsmidx == pkt->tidsmcount) { + ret = -EFAULT; + goto done; + } + } + } + + /* + * If this is NOT the last descriptor. (newlen==len) + * the current packet is not done yet, but the current + * send side page is done. + */ + if (lastdesc == 0) + goto done; + + /* + * If running this driver under PSM with message size + * fitting into one transfer unit, it is not possible + * to pass this line. otherwise, it is a buggggg. + */ + + /* + * Since the current packet is done, and there are more + * bytes togo, we need to create a new sdma header, copying + * from previous sdma header and modify both. + */ + pbclen = pkt->addr[pkt->index].length; + pbcvaddr = qib_user_sdma_alloc_header(pq, pbclen, &pbcdaddr); + if (!pbcvaddr) { + ret = -ENOMEM; + goto done; + } + /* Copy the previous sdma header to new sdma header */ + pbc16 = (__le16 *)pkt->addr[pkt->index].kvaddr; + memcpy(pbcvaddr, pbc16, pbclen); + + /* Modify the previous sdma header */ + hdr = (struct qib_message_header *)&pbc16[4]; + + /* New pbc length */ + pbc16[0] = cpu_to_le16(le16_to_cpu(pbc16[0])-(pkt->bytes_togo>>2)); + + /* New packet length */ + hdr->lrh[2] = cpu_to_be16(le16_to_cpu(pbc16[0])); + + if (pkt->tiddma) { + /* turn on the header suppression */ + hdr->iph.pkt_flags = + cpu_to_le16(le16_to_cpu(hdr->iph.pkt_flags)|0x2); + /* turn off ACK_REQ: 0x04 and EXPECTED_DONE: 0x20 */ + hdr->flags &= ~(0x04|0x20); + } else { + /* turn off extra bytes: 20-21 bits */ + hdr->bth[0] = cpu_to_be32(be32_to_cpu(hdr->bth[0])&0xFFCFFFFF); + /* turn off ACK_REQ: 0x04 */ + hdr->flags &= ~(0x04); + } + + /* New kdeth checksum */ + vcto = le32_to_cpu(hdr->iph.ver_ctxt_tid_offset); + hdr->iph.chksum = cpu_to_le16(QIB_LRH_BTH + + be16_to_cpu(hdr->lrh[2]) - + ((vcto>>16)&0xFFFF) - (vcto&0xFFFF) - + le16_to_cpu(hdr->iph.pkt_flags)); + + /* The packet is done, header is not dma mapped yet. + * it should be from kmalloc */ + if (!pkt->addr[pkt->index].addr) { + pkt->addr[pkt->index].addr = + dma_map_single(&dd->pcidev->dev, + pkt->addr[pkt->index].kvaddr, + pkt->addr[pkt->index].dma_length, + DMA_TO_DEVICE); + if (dma_mapping_error(&dd->pcidev->dev, + pkt->addr[pkt->index].addr)) { + ret = -ENOMEM; + goto done; + } + pkt->addr[pkt->index].dma_mapped = 1; + } + + /* Modify the new sdma header */ + pbc16 = (__le16 *)pbcvaddr; + hdr = (struct qib_message_header *)&pbc16[4]; + + /* New pbc length */ + pbc16[0] = cpu_to_le16(le16_to_cpu(pbc16[0])-(pkt->payload_size>>2)); + + /* New packet length */ + hdr->lrh[2] = cpu_to_be16(le16_to_cpu(pbc16[0])); + + if (pkt->tiddma) { + /* Set new tid and offset for new sdma header */ + hdr->iph.ver_ctxt_tid_offset = cpu_to_le32( + (le32_to_cpu(hdr->iph.ver_ctxt_tid_offset)&0xFF000000) + + (pkt->tidsm[pkt->tidsmidx].tid<<QLOGIC_IB_I_TID_SHIFT) + + (pkt->tidsm[pkt->tidsmidx].offset>>2)); + } else { + /* Middle protocol new packet offset */ + hdr->uwords[2] += pkt->payload_size; + } + + /* New kdeth checksum */ + vcto = le32_to_cpu(hdr->iph.ver_ctxt_tid_offset); + hdr->iph.chksum = cpu_to_le16(QIB_LRH_BTH + + be16_to_cpu(hdr->lrh[2]) - + ((vcto>>16)&0xFFFF) - (vcto&0xFFFF) - + le16_to_cpu(hdr->iph.pkt_flags)); + + /* Next sequence number in new sdma header */ + seqnum.val = be32_to_cpu(hdr->bth[2]); + if (pkt->tiddma) + seqnum.seq++; + else + seqnum.pkt++; + hdr->bth[2] = cpu_to_be32(seqnum.val); + + /* Init new sdma header. */ + qib_user_sdma_init_frag(pkt, pkt->naddr, /* index */ + 0, pbclen, /* offset, len */ + 1, 0, /* first last desc */ + 0, 0, /* put page, dma mapped */ + NULL, pbcvaddr, /* struct page, virt addr */ + pbcdaddr, pbclen); /* dma addr, dma length */ + pkt->index = pkt->naddr; + pkt->payload_size = 0; + pkt->naddr++; + if (pkt->naddr == pkt->addrlimit) { + ret = -EFAULT; + goto done; + } + + /* Prepare for next fragment in this page */ + if (newlen != len) { + if (dma_mapped) { + put = 0; + dma_mapped = 0; + page = NULL; + kvaddr = NULL; + } + len -= newlen; + offset += newlen; + + goto next_fragment; + } + +done: + return ret; +} + +/* 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_queue *pq, + 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; + + 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; + } + + ret = qib_user_sdma_page_to_frags(dd, pq, pkt, + page, 0, 0, len, mpage_save); + goto done; + +free_unmap: + kunmap(page); + __free_page(page); +done: + return ret; +} + +/* + * How many pages in this iovec element? + */ +static size_t 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); +} + +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) { + /* only user data has page */ + if (pkt->addr[i].dma_mapped) + dma_unmap_page(dev, + pkt->addr[i].addr, + pkt->addr[i].dma_length, + DMA_TO_DEVICE); + + if (pkt->addr[i].kvaddr) + kunmap(pkt->addr[i].page); + + if (pkt->addr[i].put_page) + unpin_user_page(pkt->addr[i].page); + else + __free_page(pkt->addr[i].page); + } else if (pkt->addr[i].kvaddr) { + /* for headers */ + if (pkt->addr[i].dma_mapped) { + /* from kmalloc & dma mapped */ + dma_unmap_single(dev, + pkt->addr[i].addr, + pkt->addr[i].dma_length, + DMA_TO_DEVICE); + kfree(pkt->addr[i].kvaddr); + } else if (pkt->addr[i].addr) { + /* free coherent mem from cache... */ + dma_pool_free(pq->header_cache, + pkt->addr[i].kvaddr, pkt->addr[i].addr); + } else { + /* from kmalloc but not dma mapped */ + kfree(pkt->addr[i].kvaddr); + } + } +} + +/* return number of pages pinned... */ +static int qib_user_sdma_pin_pages(const struct qib_devdata *dd, + struct qib_user_sdma_queue *pq, + struct qib_user_sdma_pkt *pkt, + unsigned long addr, int tlen, size_t npages) +{ + struct page *pages[8]; + int i, j; + int ret = 0; + + while (npages) { + if (npages > 8) + j = 8; + else + j = npages; + + ret = pin_user_pages_fast(addr, j, FOLL_LONGTERM, pages); + if (ret != j) { + i = 0; + j = ret; + ret = -ENOMEM; + goto free_pages; + } + + for (i = 0; i < j; i++) { + /* map the pages... */ + unsigned long fofs = addr & ~PAGE_MASK; + int flen = ((fofs + tlen) > PAGE_SIZE) ? + (PAGE_SIZE - fofs) : tlen; + + ret = qib_user_sdma_page_to_frags(dd, pq, pkt, + pages[i], 1, fofs, flen, NULL); + if (ret < 0) { + /* current page has beed taken + * care of inside above call. + */ + i++; + goto free_pages; + } + + addr += flen; + tlen -= flen; + } + + npages -= j; + } + + goto done; + + /* if error, return all pages not managed by pkt */ +free_pages: + while (i < j) + unpin_user_page(pages[i++]); + +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 size_t 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, pq, pkt, addr, + iov[idx].iov_len, npages); + if (ret < 0) + goto free_pkt; + } + + goto done; + +free_pkt: + /* we need to ignore the first entry here */ + for (idx = 1; idx < pkt->naddr; idx++) + qib_user_sdma_free_pkt_frag(&dd->pcidev->dev, pq, pkt, idx); + + /* need to dma unmap the first entry, this is to restore to + * the original state so that caller can free the memory in + * error condition. Caller does not know if dma mapped or not*/ + if (pkt->addr[0].dma_mapped) { + dma_unmap_single(&dd->pcidev->dev, + pkt->addr[0].addr, + pkt->addr[0].dma_length, + DMA_TO_DEVICE); + pkt->addr[0].addr = 0; + pkt->addr[0].dma_mapped = 0; + } + +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 (pkt->frag_size == pkt->bytes_togo && + npages >= ARRAY_SIZE(pkt->addr)) + ret = qib_user_sdma_coalesce(dd, pq, 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); + + if (pkt->largepkt) + kfree(pkt); + else + 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_pportdata *ppd, + struct qib_user_sdma_queue *pq, + const struct iovec *iov, + unsigned long niov, + struct list_head *list, + int *maxpkts, int *ndesc) +{ + unsigned long idx = 0; + int ret = 0; + int npkts = 0; + __le32 *pbc; + dma_addr_t dma_addr; + struct qib_user_sdma_pkt *pkt = NULL; + size_t len; + size_t nw; + u32 counter = pq->counter; + u16 frag_size; + + 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; + size_t npages = 0; + size_t bytes_togo = 0; + int tiddma = 0; + int cfur; + + len = iov[idx].iov_len; + nw = len >> 2; + + if (len < QIB_USER_SDMA_MIN_HEADER_LENGTH || + len > PAGE_SIZE || len & 3 || addr & 3) { + ret = -EINVAL; + goto free_list; + } + + pbc = qib_user_sdma_alloc_header(pq, len, &dma_addr); + if (!pbc) { + ret = -ENOMEM; + goto free_list; + } + + 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) & 0xFFFF; + if (pktnw < pktnwc) { + 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) { + ret = -EINVAL; + goto free_pbc; + } + + npages += qib_user_sdma_num_pages(&iov[idx]); + + if (check_add_overflow(bytes_togo, slen, &bytes_togo) || + bytes_togo > type_max(typeof(pkt->bytes_togo))) { + ret = -EINVAL; + goto free_pbc; + } + pktnwc += slen >> 2; + idx++; + nfrags++; + } + + if (pktnwc != pktnw) { + ret = -EINVAL; + goto free_pbc; + } + + frag_size = ((le32_to_cpu(*pbc))>>16) & 0xFFFF; + if (((frag_size ? frag_size : bytes_togo) + len) > + ppd->ibmaxlen) { + ret = -EINVAL; + goto free_pbc; + } + + if (frag_size) { + size_t tidsmsize, n, pktsize, sz, addrlimit; + + n = npages*((2*PAGE_SIZE/frag_size)+1); + pktsize = struct_size(pkt, addr, n); + + /* + * Determine if this is tid-sdma or just sdma. + */ + tiddma = (((le32_to_cpu(pbc[7])>> + QLOGIC_IB_I_TID_SHIFT)& + QLOGIC_IB_I_TID_MASK) != + QLOGIC_IB_I_TID_MASK); + + if (tiddma) + tidsmsize = iov[idx].iov_len; + else + tidsmsize = 0; + + if (check_add_overflow(pktsize, tidsmsize, &sz)) { + ret = -EINVAL; + goto free_pbc; + } + pkt = kmalloc(sz, GFP_KERNEL); + if (!pkt) { + ret = -ENOMEM; + goto free_pbc; + } + pkt->largepkt = 1; + pkt->frag_size = frag_size; + if (check_add_overflow(n, ARRAY_SIZE(pkt->addr), + &addrlimit) || + addrlimit > type_max(typeof(pkt->addrlimit))) { + ret = -EINVAL; + goto free_pkt; + } + pkt->addrlimit = addrlimit; + + if (tiddma) { + char *tidsm = (char *)pkt + pktsize; + + cfur = copy_from_user(tidsm, + iov[idx].iov_base, tidsmsize); + if (cfur) { + ret = -EFAULT; + goto free_pkt; + } + pkt->tidsm = + (struct qib_tid_session_member *)tidsm; + pkt->tidsmcount = tidsmsize/ + sizeof(struct qib_tid_session_member); + pkt->tidsmidx = 0; + idx++; + } + + /* + * pbc 'fill1' field is borrowed to pass frag size, + * we need to clear it after picking frag size, the + * hardware requires this field to be zero. + */ + *pbc = cpu_to_le32(le32_to_cpu(*pbc) & 0x0000FFFF); + } else { + pkt = kmem_cache_alloc(pq->pkt_slab, GFP_KERNEL); + if (!pkt) { + ret = -ENOMEM; + goto free_pbc; + } + pkt->largepkt = 0; + pkt->frag_size = bytes_togo; + pkt->addrlimit = ARRAY_SIZE(pkt->addr); + } + pkt->bytes_togo = bytes_togo; + pkt->payload_size = 0; + pkt->counter = counter; + pkt->tiddma = tiddma; + + /* setup the first header */ + qib_user_sdma_init_frag(pkt, 0, /* index */ + 0, len, /* offset, len */ + 1, 0, /* first last desc */ + 0, 0, /* put page, dma mapped */ + NULL, pbc, /* struct page, virt addr */ + dma_addr, len); /* dma addr, dma length */ + pkt->index = 0; + pkt->naddr = 1; + + if (nfrags) { + ret = qib_user_sdma_init_payload(dd, pq, pkt, + iov + idx_save + 1, + nfrags, npages); + if (ret < 0) + goto free_pkt; + } else { + /* since there is no payload, mark the + * header as the last desc. */ + pkt->addr[0].last_desc = 1; + + if (dma_addr == 0) { + /* + * the header is not dma mapped yet. + * it should be from kmalloc. + */ + dma_addr = dma_map_single(&dd->pcidev->dev, + pbc, len, DMA_TO_DEVICE); + if (dma_mapping_error(&dd->pcidev->dev, + dma_addr)) { + ret = -ENOMEM; + goto free_pkt; + } + pkt->addr[0].addr = dma_addr; + pkt->addr[0].dma_mapped = 1; + } + } + + counter++; + npkts++; + pkt->pq = pq; + pkt->index = 0; /* reset index for push on hw */ + *ndesc += pkt->naddr; + + list_add_tail(&pkt->list, list); + } + + *maxpkts = npkts; + ret = idx; + goto done; + +free_pkt: + if (pkt->largepkt) + kfree(pkt); + else + kmem_cache_free(pq->pkt_slab, pkt); +free_pbc: + if (dma_addr) + dma_pool_free(pq->header_cache, pbc, dma_addr); + else + kfree(pbc); +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; + unsigned long flags; + int ret = 0; + + if (!pq->num_sending) + return 0; + + INIT_LIST_HEAD(&free_list); + + /* + * We need this spin lock here because interrupt handler + * might modify this list in qib_user_sdma_send_desc(), also + * we can not get interrupted, otherwise it is a deadlock. + */ + spin_lock_irqsave(&pq->sent_lock, flags); + 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++; + pq->num_sending--; + } + spin_unlock_irqrestore(&pq->sent_lock, flags); + + 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; + + pq->sdma_rb_node->refcount--; + if (pq->sdma_rb_node->refcount == 0) { + rb_erase(&pq->sdma_rb_node->node, &qib_user_sdma_rb_root); + kfree(pq->sdma_rb_node); + } + dma_pool_destroy(pq->header_cache); + kmem_cache_destroy(pq->pkt_slab); + 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; + unsigned long flags; + int i; + + if (!pq) + return; + + for (i = 0; i < QIB_USER_SDMA_DRAIN_TIMEOUT; i++) { + mutex_lock(&pq->lock); + if (!pq->num_pending && !pq->num_sending) { + mutex_unlock(&pq->lock); + break; + } + qib_user_sdma_hwqueue_clean(ppd); + qib_user_sdma_queue_clean(ppd, pq); + mutex_unlock(&pq->lock); + msleep(20); + } + + if (pq->num_pending || pq->num_sending) { + struct qib_user_sdma_pkt *pkt; + struct qib_user_sdma_pkt *pkt_prev; + struct list_head free_list; + + mutex_lock(&pq->lock); + spin_lock_irqsave(&ppd->sdma_lock, flags); + /* + * Since we hold sdma_lock, it is safe without sent_lock. + */ + if (pq->num_pending) { + list_for_each_entry_safe(pkt, pkt_prev, + &ppd->sdma_userpending, list) { + if (pkt->pq == pq) { + list_move_tail(&pkt->list, &pq->sent); + pq->num_pending--; + pq->num_sending++; + } + } + } + spin_unlock_irqrestore(&ppd->sdma_lock, flags); + + qib_dev_err(dd, "user sdma lists not empty: forcing!\n"); + INIT_LIST_HEAD(&free_list); + list_splice_init(&pq->sent, &free_list); + pq->num_sending = 0; + qib_user_sdma_free_pkt_list(&dd->pcidev->dev, pq, &free_list); + mutex_unlock(&pq->lock); + } +} + +static inline __le64 qib_sdma_make_desc0(u8 gen, + u64 addr, u64 dwlen, u64 dwoffset) +{ + return cpu_to_le64(/* SDmaPhyAddr[31:0] */ + ((addr & 0xfffffffcULL) << 32) | + /* SDmaGeneration[1:0] */ + ((gen & 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, u8 gen) +{ + 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(gen, addr, dwlen, ofs); + if (pkt->addr[idx].first_desc) + descq0 = qib_sdma_make_first_desc0(descq0); + if (pkt->addr[idx].last_desc) { + descq0 = qib_sdma_make_last_desc0(descq0); + if (ppd->sdma_intrequest) { + descq0 |= cpu_to_le64(1ULL << 15); + ppd->sdma_intrequest = 0; + } + } + + descqp[0] = descq0; + descqp[1] = qib_sdma_make_desc1(addr); +} + +void qib_user_sdma_send_desc(struct qib_pportdata *ppd, + struct list_head *pktlist) +{ + struct qib_devdata *dd = ppd->dd; + u16 nfree, nsent; + u16 tail, tail_c; + u8 gen, gen_c; + + nfree = qib_sdma_descq_freecnt(ppd); + if (!nfree) + return; + +retry: + nsent = 0; + tail_c = tail = ppd->sdma_descq_tail; + gen_c = gen = ppd->sdma_generation; + while (!list_empty(pktlist)) { + struct qib_user_sdma_pkt *pkt = + list_entry(pktlist->next, struct qib_user_sdma_pkt, + list); + int i, j, c = 0; + unsigned ofs = 0; + u16 dtail = tail; + + for (i = pkt->index; i < pkt->naddr && nfree; i++) { + qib_user_sdma_send_frag(ppd, pkt, i, ofs, tail, gen); + ofs += pkt->addr[i].length >> 2; + + if (++tail == ppd->sdma_descq_cnt) { + tail = 0; + ++gen; + ppd->sdma_intrequest = 1; + } else if (tail == (ppd->sdma_descq_cnt>>1)) { + ppd->sdma_intrequest = 1; + } + nfree--; + if (pkt->addr[i].last_desc == 0) + continue; + + /* + * 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 (j = pkt->index; j <= i; j++) { + ppd->sdma_descq[dtail].qw[0] |= + cpu_to_le64(1ULL << 14); + if (++dtail == ppd->sdma_descq_cnt) + dtail = 0; + } + } + c += i + 1 - pkt->index; + pkt->index = i + 1; /* index for next first */ + tail_c = dtail = tail; + gen_c = gen; + ofs = 0; /* reset for next packet */ + } + + ppd->sdma_descq_added += c; + nsent += c; + if (pkt->index == pkt->naddr) { + pkt->added = ppd->sdma_descq_added; + pkt->pq->added = pkt->added; + pkt->pq->num_pending--; + spin_lock(&pkt->pq->sent_lock); + pkt->pq->num_sending++; + list_move_tail(&pkt->list, &pkt->pq->sent); + spin_unlock(&pkt->pq->sent_lock); + } + if (!nfree || (nsent<<2) > ppd->sdma_descq_cnt) + break; + } + + /* advance the tail on the chip if necessary */ + if (ppd->sdma_descq_tail != tail_c) { + ppd->sdma_generation = gen_c; + dd->f_sdma_update_tail(ppd, tail_c); + } + + if (nfree && !list_empty(pktlist)) + goto retry; +} + +/* 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, int count) +{ + unsigned long flags; + + if (unlikely(!(ppd->lflags & QIBL_LINKACTIVE))) + return -ECOMM; + + /* non-blocking mode */ + if (pq->sdma_rb_node->refcount > 1) { + spin_lock_irqsave(&ppd->sdma_lock, flags); + if (unlikely(!__qib_sdma_running(ppd))) { + spin_unlock_irqrestore(&ppd->sdma_lock, flags); + return -ECOMM; + } + pq->num_pending += count; + list_splice_tail_init(pktlist, &ppd->sdma_userpending); + qib_user_sdma_send_desc(ppd, &ppd->sdma_userpending); + spin_unlock_irqrestore(&ppd->sdma_lock, flags); + return 0; + } + + /* In this case, descriptors from this process are not + * linked to ppd pending queue, interrupt handler + * won't update this process, it is OK to directly + * modify without sdma lock. + */ + + + pq->num_pending += count; + /* + * Blocking mode for single rail process, we must + * release/regain sdma_lock to give other process + * chance to make progress. This is important for + * performance. + */ + do { + spin_lock_irqsave(&ppd->sdma_lock, flags); + if (unlikely(!__qib_sdma_running(ppd))) { + spin_unlock_irqrestore(&ppd->sdma_lock, flags); + return -ECOMM; + } + qib_user_sdma_send_desc(ppd, pktlist); + if (!list_empty(pktlist)) + qib_sdma_make_progress(ppd); + spin_unlock_irqrestore(&ppd->sdma_lock, flags); + } while (!list_empty(pktlist)); + + return 0; +} + +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 I have packets not complete yet */ + if (pq->added > ppd->sdma_descq_removed) + qib_user_sdma_hwqueue_clean(ppd); + /* if I have complete packets to be freed */ + if (pq->num_sending) + qib_user_sdma_queue_clean(ppd, pq); + + while (dim) { + int mxp = 1; + int ndesc = 0; + + ret = qib_user_sdma_queue_pkts(dd, ppd, pq, + iov, dim, &list, &mxp, &ndesc); + 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. + */ + if (qib_sdma_descq_freecnt(ppd) < ndesc) { + qib_user_sdma_hwqueue_clean(ppd); + if (pq->num_sending) + qib_user_sdma_queue_clean(ppd, pq); + } + + ret = qib_user_sdma_push_pkts(ppd, pq, &list, mxp); + if (ret < 0) + goto done_unlock; + else { + npkts += mxp; + pq->counter += mxp; + } + } + } + +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; +} |