From d69d235b7da2778891640ee95efcd68075978904 Mon Sep 17 00:00:00 2001 From: Dan Williams Date: Tue, 8 Sep 2009 17:42:59 -0700 Subject: [PATCH] ioat3: pq support ioat3.2 adds support for raid6 syndrome generation (xor sum of galois field multiplication products) using up to 8 sources. It can also perform an pq-zero-sum operation to validate whether the syndrome for a given set of sources matches a previously computed syndrome. Signed-off-by: Dan Williams --- drivers/dma/ioat/dma_v3.c | 265 +++++++++++++++++++++++++++++++++++++- 1 file changed, 264 insertions(+), 1 deletion(-) diff --git a/drivers/dma/ioat/dma_v3.c b/drivers/dma/ioat/dma_v3.c index 927c08b08861..ca2af0fa1c36 100644 --- a/drivers/dma/ioat/dma_v3.c +++ b/drivers/dma/ioat/dma_v3.c @@ -69,10 +69,12 @@ #define src_cnt_to_hw(x) ((x) - 2) /* provide a lookup table for setting the source address in the base or - * extended descriptor of an xor descriptor + * extended descriptor of an xor or pq descriptor */ static const u8 xor_idx_to_desc __read_mostly = 0xd0; static const u8 xor_idx_to_field[] __read_mostly = { 1, 4, 5, 6, 7, 0, 1, 2 }; +static const u8 pq_idx_to_desc __read_mostly = 0xf8; +static const u8 pq_idx_to_field[] __read_mostly = { 1, 4, 5, 0, 1, 2, 4, 5 }; static dma_addr_t xor_get_src(struct ioat_raw_descriptor *descs[2], int idx) { @@ -89,6 +91,23 @@ static void xor_set_src(struct ioat_raw_descriptor *descs[2], raw->field[xor_idx_to_field[idx]] = addr + offset; } +static dma_addr_t pq_get_src(struct ioat_raw_descriptor *descs[2], int idx) +{ + struct ioat_raw_descriptor *raw = descs[pq_idx_to_desc >> idx & 1]; + + return raw->field[pq_idx_to_field[idx]]; +} + +static void pq_set_src(struct ioat_raw_descriptor *descs[2], + dma_addr_t addr, u32 offset, u8 coef, int idx) +{ + struct ioat_pq_descriptor *pq = (struct ioat_pq_descriptor *) descs[0]; + struct ioat_raw_descriptor *raw = descs[pq_idx_to_desc >> idx & 1]; + + raw->field[pq_idx_to_field[idx]] = addr + offset; + pq->coef[idx] = coef; +} + static void ioat3_dma_unmap(struct ioat2_dma_chan *ioat, struct ioat_ring_ent *desc, int idx) { @@ -148,6 +167,58 @@ static void ioat3_dma_unmap(struct ioat2_dma_chan *ioat, PCI_DMA_FROMDEVICE, flags, 1); break; } + case IOAT_OP_PQ_VAL: + case IOAT_OP_PQ: { + struct ioat_pq_descriptor *pq = desc->pq; + struct ioat_ring_ent *ext; + struct ioat_pq_ext_descriptor *pq_ex = NULL; + int src_cnt = src_cnt_to_sw(pq->ctl_f.src_cnt); + struct ioat_raw_descriptor *descs[2]; + int i; + + if (src_cnt > 3) { + ext = ioat2_get_ring_ent(ioat, idx + 1); + pq_ex = ext->pq_ex; + } + + /* in the 'continue' case don't unmap the dests as sources */ + if (dmaf_p_disabled_continue(flags)) + src_cnt--; + else if (dmaf_continue(flags)) + src_cnt -= 3; + + if (!(flags & DMA_COMPL_SKIP_SRC_UNMAP)) { + descs[0] = (struct ioat_raw_descriptor *) pq; + descs[1] = (struct ioat_raw_descriptor *) pq_ex; + for (i = 0; i < src_cnt; i++) { + dma_addr_t src = pq_get_src(descs, i); + + ioat_unmap(pdev, src - offset, len, + PCI_DMA_TODEVICE, flags, 0); + } + + /* the dests are sources in pq validate operations */ + if (pq->ctl_f.op == IOAT_OP_XOR_VAL) { + if (!(flags & DMA_PREP_PQ_DISABLE_P)) + ioat_unmap(pdev, pq->p_addr - offset, + len, PCI_DMA_TODEVICE, flags, 0); + if (!(flags & DMA_PREP_PQ_DISABLE_Q)) + ioat_unmap(pdev, pq->q_addr - offset, + len, PCI_DMA_TODEVICE, flags, 0); + break; + } + } + + if (!(flags & DMA_COMPL_SKIP_DEST_UNMAP)) { + if (!(flags & DMA_PREP_PQ_DISABLE_P)) + ioat_unmap(pdev, pq->p_addr - offset, len, + PCI_DMA_BIDIRECTIONAL, flags, 1); + if (!(flags & DMA_PREP_PQ_DISABLE_Q)) + ioat_unmap(pdev, pq->q_addr - offset, len, + PCI_DMA_BIDIRECTIONAL, flags, 1); + } + break; + } default: dev_err(&pdev->dev, "%s: unknown op type: %#x\n", __func__, desc->hw->ctl_f.op); @@ -164,6 +235,12 @@ static bool desc_has_ext(struct ioat_ring_ent *desc) if (src_cnt_to_sw(xor->ctl_f.src_cnt) > 5) return true; + } else if (hw->ctl_f.op == IOAT_OP_PQ || + hw->ctl_f.op == IOAT_OP_PQ_VAL) { + struct ioat_pq_descriptor *pq = desc->pq; + + if (src_cnt_to_sw(pq->ctl_f.src_cnt) > 3) + return true; } return false; @@ -513,6 +590,182 @@ ioat3_prep_xor_val(struct dma_chan *chan, dma_addr_t *src, src_cnt - 1, len, flags); } +static void +dump_pq_desc_dbg(struct ioat2_dma_chan *ioat, struct ioat_ring_ent *desc, struct ioat_ring_ent *ext) +{ + struct device *dev = to_dev(&ioat->base); + struct ioat_pq_descriptor *pq = desc->pq; + struct ioat_pq_ext_descriptor *pq_ex = ext ? ext->pq_ex : NULL; + struct ioat_raw_descriptor *descs[] = { (void *) pq, (void *) pq_ex }; + int src_cnt = src_cnt_to_sw(pq->ctl_f.src_cnt); + int i; + + dev_dbg(dev, "desc[%d]: (%#llx->%#llx) flags: %#x" + " sz: %#x ctl: %#x (op: %d int: %d compl: %d pq: '%s%s' src_cnt: %d)\n", + desc_id(desc), (unsigned long long) desc->txd.phys, + (unsigned long long) (pq_ex ? pq_ex->next : pq->next), + desc->txd.flags, pq->size, pq->ctl, pq->ctl_f.op, pq->ctl_f.int_en, + pq->ctl_f.compl_write, + pq->ctl_f.p_disable ? "" : "p", pq->ctl_f.q_disable ? "" : "q", + pq->ctl_f.src_cnt); + for (i = 0; i < src_cnt; i++) + dev_dbg(dev, "\tsrc[%d]: %#llx coef: %#x\n", i, + (unsigned long long) pq_get_src(descs, i), pq->coef[i]); + dev_dbg(dev, "\tP: %#llx\n", pq->p_addr); + dev_dbg(dev, "\tQ: %#llx\n", pq->q_addr); +} + +static struct dma_async_tx_descriptor * +__ioat3_prep_pq_lock(struct dma_chan *c, enum sum_check_flags *result, + const dma_addr_t *dst, const dma_addr_t *src, + unsigned int src_cnt, const unsigned char *scf, + size_t len, unsigned long flags) +{ + struct ioat2_dma_chan *ioat = to_ioat2_chan(c); + struct ioat_chan_common *chan = &ioat->base; + struct ioat_ring_ent *compl_desc; + struct ioat_ring_ent *desc; + struct ioat_ring_ent *ext; + size_t total_len = len; + struct ioat_pq_descriptor *pq; + struct ioat_pq_ext_descriptor *pq_ex = NULL; + struct ioat_dma_descriptor *hw; + u32 offset = 0; + int num_descs; + int with_ext; + int i, s; + u16 idx; + u8 op = result ? IOAT_OP_PQ_VAL : IOAT_OP_PQ; + + dev_dbg(to_dev(chan), "%s\n", __func__); + /* the engine requires at least two sources (we provide + * at least 1 implied source in the DMA_PREP_CONTINUE case) + */ + BUG_ON(src_cnt + dmaf_continue(flags) < 2); + + num_descs = ioat2_xferlen_to_descs(ioat, len); + /* we need 2x the number of descriptors to cover greater than 3 + * sources + */ + if (src_cnt > 3 || flags & DMA_PREP_CONTINUE) { + with_ext = 1; + num_descs *= 2; + } else + with_ext = 0; + + /* completion writes from the raid engine may pass completion + * writes from the legacy engine, so we need one extra null + * (legacy) descriptor to ensure all completion writes arrive in + * order. + */ + if (likely(num_descs) && + ioat2_alloc_and_lock(&idx, ioat, num_descs+1) == 0) + /* pass */; + else + return NULL; + for (i = 0; i < num_descs; i += 1 + with_ext) { + struct ioat_raw_descriptor *descs[2]; + size_t xfer_size = min_t(size_t, len, 1 << ioat->xfercap_log); + + desc = ioat2_get_ring_ent(ioat, idx + i); + pq = desc->pq; + + /* save a branch by unconditionally retrieving the + * extended descriptor pq_set_src() knows to not write + * to it in the single descriptor case + */ + ext = ioat2_get_ring_ent(ioat, idx + i + with_ext); + pq_ex = ext->pq_ex; + + descs[0] = (struct ioat_raw_descriptor *) pq; + descs[1] = (struct ioat_raw_descriptor *) pq_ex; + + for (s = 0; s < src_cnt; s++) + pq_set_src(descs, src[s], offset, scf[s], s); + + /* see the comment for dma_maxpq in include/linux/dmaengine.h */ + if (dmaf_p_disabled_continue(flags)) + pq_set_src(descs, dst[1], offset, 1, s++); + else if (dmaf_continue(flags)) { + pq_set_src(descs, dst[0], offset, 0, s++); + pq_set_src(descs, dst[1], offset, 1, s++); + pq_set_src(descs, dst[1], offset, 0, s++); + } + pq->size = xfer_size; + pq->p_addr = dst[0] + offset; + pq->q_addr = dst[1] + offset; + pq->ctl = 0; + pq->ctl_f.op = op; + pq->ctl_f.src_cnt = src_cnt_to_hw(s); + pq->ctl_f.p_disable = !!(flags & DMA_PREP_PQ_DISABLE_P); + pq->ctl_f.q_disable = !!(flags & DMA_PREP_PQ_DISABLE_Q); + + len -= xfer_size; + offset += xfer_size; + } + + /* last pq descriptor carries the unmap parameters and fence bit */ + desc->txd.flags = flags; + desc->len = total_len; + if (result) + desc->result = result; + pq->ctl_f.fence = !!(flags & DMA_PREP_FENCE); + dump_pq_desc_dbg(ioat, desc, ext); + + /* completion descriptor carries interrupt bit */ + compl_desc = ioat2_get_ring_ent(ioat, idx + i); + compl_desc->txd.flags = flags & DMA_PREP_INTERRUPT; + hw = compl_desc->hw; + hw->ctl = 0; + hw->ctl_f.null = 1; + hw->ctl_f.int_en = !!(flags & DMA_PREP_INTERRUPT); + hw->ctl_f.compl_write = 1; + hw->size = NULL_DESC_BUFFER_SIZE; + dump_desc_dbg(ioat, compl_desc); + + /* we leave the channel locked to ensure in order submission */ + return &desc->txd; +} + +static struct dma_async_tx_descriptor * +ioat3_prep_pq(struct dma_chan *chan, dma_addr_t *dst, dma_addr_t *src, + unsigned int src_cnt, const unsigned char *scf, size_t len, + unsigned long flags) +{ + /* handle the single source multiply case from the raid6 + * recovery path + */ + if (unlikely((flags & DMA_PREP_PQ_DISABLE_P) && src_cnt == 1)) { + dma_addr_t single_source[2]; + unsigned char single_source_coef[2]; + + BUG_ON(flags & DMA_PREP_PQ_DISABLE_Q); + single_source[0] = src[0]; + single_source[1] = src[0]; + single_source_coef[0] = scf[0]; + single_source_coef[1] = 0; + + return __ioat3_prep_pq_lock(chan, NULL, dst, single_source, 2, + single_source_coef, len, flags); + } else + return __ioat3_prep_pq_lock(chan, NULL, dst, src, src_cnt, scf, + len, flags); +} + +struct dma_async_tx_descriptor * +ioat3_prep_pq_val(struct dma_chan *chan, dma_addr_t *pq, dma_addr_t *src, + unsigned int src_cnt, const unsigned char *scf, size_t len, + enum sum_check_flags *pqres, unsigned long flags) +{ + /* the cleanup routine only sets bits on validate failure, it + * does not clear bits on validate success... so clear it here + */ + *pqres = 0; + + return __ioat3_prep_pq_lock(chan, pqres, pq, src, src_cnt, scf, len, + flags); +} + static void __devinit ioat3_dma_test_callback(void *dma_async_param) { struct completion *cmp = dma_async_param; @@ -822,6 +1075,16 @@ int __devinit ioat3_dma_probe(struct ioatdma_device *device, int dca) dma_cap_set(DMA_XOR_VAL, dma->cap_mask); dma->device_prep_dma_xor_val = ioat3_prep_xor_val; } + if (cap & IOAT_CAP_PQ) { + dma_set_maxpq(dma, 8, 0); + dma->pq_align = 2; + + dma_cap_set(DMA_PQ, dma->cap_mask); + dma->device_prep_dma_pq = ioat3_prep_pq; + + dma_cap_set(DMA_PQ_VAL, dma->cap_mask); + dma->device_prep_dma_pq_val = ioat3_prep_pq_val; + } /* -= IOAT ver.3 workarounds =- */ /* Write CHANERRMSK_INT with 3E07h to mask out the errors -- 2.39.2