diff options
Diffstat (limited to 'kernel/crypto/async_tx')
| -rw-r--r-- | kernel/crypto/async_tx/Kconfig | 27 | ||||
| -rw-r--r-- | kernel/crypto/async_tx/Makefile | 6 | ||||
| -rw-r--r-- | kernel/crypto/async_tx/async_memcpy.c | 110 | ||||
| -rw-r--r-- | kernel/crypto/async_tx/async_pq.c | 454 | ||||
| -rw-r--r-- | kernel/crypto/async_tx/async_raid6_recov.c | 531 | ||||
| -rw-r--r-- | kernel/crypto/async_tx/async_tx.c | 294 | ||||
| -rw-r--r-- | kernel/crypto/async_tx/async_xor.c | 345 | ||||
| -rw-r--r-- | kernel/crypto/async_tx/raid6test.c | 253 |
8 files changed, 2020 insertions, 0 deletions
diff --git a/kernel/crypto/async_tx/Kconfig b/kernel/crypto/async_tx/Kconfig new file mode 100644 index 000000000..f38a58aef --- /dev/null +++ b/kernel/crypto/async_tx/Kconfig @@ -0,0 +1,27 @@ +config ASYNC_CORE + tristate + +config ASYNC_MEMCPY + tristate + select ASYNC_CORE + +config ASYNC_XOR + tristate + select ASYNC_CORE + select XOR_BLOCKS + +config ASYNC_PQ + tristate + select ASYNC_CORE + +config ASYNC_RAID6_RECOV + tristate + select ASYNC_CORE + select ASYNC_PQ + select ASYNC_XOR + +config ASYNC_TX_DISABLE_PQ_VAL_DMA + bool + +config ASYNC_TX_DISABLE_XOR_VAL_DMA + bool diff --git a/kernel/crypto/async_tx/Makefile b/kernel/crypto/async_tx/Makefile new file mode 100644 index 000000000..462e4abbf --- /dev/null +++ b/kernel/crypto/async_tx/Makefile @@ -0,0 +1,6 @@ +obj-$(CONFIG_ASYNC_CORE) += async_tx.o +obj-$(CONFIG_ASYNC_MEMCPY) += async_memcpy.o +obj-$(CONFIG_ASYNC_XOR) += async_xor.o +obj-$(CONFIG_ASYNC_PQ) += async_pq.o +obj-$(CONFIG_ASYNC_RAID6_RECOV) += async_raid6_recov.o +obj-$(CONFIG_ASYNC_RAID6_TEST) += raid6test.o diff --git a/kernel/crypto/async_tx/async_memcpy.c b/kernel/crypto/async_tx/async_memcpy.c new file mode 100644 index 000000000..f8c0b8dbe --- /dev/null +++ b/kernel/crypto/async_tx/async_memcpy.c @@ -0,0 +1,110 @@ +/* + * copy offload engine support + * + * Copyright © 2006, Intel Corporation. + * + * Dan Williams <dan.j.williams@intel.com> + * + * with architecture considerations by: + * Neil Brown <neilb@suse.de> + * Jeff Garzik <jeff@garzik.org> + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions of the GNU General Public License, + * version 2, as published by the Free Software Foundation. + * + * This program is distributed in the hope it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + * + * You should have received a copy of the GNU General Public License along with + * this program; if not, write to the Free Software Foundation, Inc., + * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA. + * + */ +#include <linux/kernel.h> +#include <linux/highmem.h> +#include <linux/module.h> +#include <linux/mm.h> +#include <linux/dma-mapping.h> +#include <linux/async_tx.h> + +/** + * async_memcpy - attempt to copy memory with a dma engine. + * @dest: destination page + * @src: src page + * @dest_offset: offset into 'dest' to start transaction + * @src_offset: offset into 'src' to start transaction + * @len: length in bytes + * @submit: submission / completion modifiers + * + * honored flags: ASYNC_TX_ACK + */ +struct dma_async_tx_descriptor * +async_memcpy(struct page *dest, struct page *src, unsigned int dest_offset, + unsigned int src_offset, size_t len, + struct async_submit_ctl *submit) +{ + struct dma_chan *chan = async_tx_find_channel(submit, DMA_MEMCPY, + &dest, 1, &src, 1, len); + struct dma_device *device = chan ? chan->device : NULL; + struct dma_async_tx_descriptor *tx = NULL; + struct dmaengine_unmap_data *unmap = NULL; + + if (device) + unmap = dmaengine_get_unmap_data(device->dev, 2, GFP_NOIO); + + if (unmap && is_dma_copy_aligned(device, src_offset, dest_offset, len)) { + unsigned long dma_prep_flags = 0; + + if (submit->cb_fn) + dma_prep_flags |= DMA_PREP_INTERRUPT; + if (submit->flags & ASYNC_TX_FENCE) + dma_prep_flags |= DMA_PREP_FENCE; + + unmap->to_cnt = 1; + unmap->addr[0] = dma_map_page(device->dev, src, src_offset, len, + DMA_TO_DEVICE); + unmap->from_cnt = 1; + unmap->addr[1] = dma_map_page(device->dev, dest, dest_offset, len, + DMA_FROM_DEVICE); + unmap->len = len; + + tx = device->device_prep_dma_memcpy(chan, unmap->addr[1], + unmap->addr[0], len, + dma_prep_flags); + } + + if (tx) { + pr_debug("%s: (async) len: %zu\n", __func__, len); + + dma_set_unmap(tx, unmap); + async_tx_submit(chan, tx, submit); + } else { + void *dest_buf, *src_buf; + pr_debug("%s: (sync) len: %zu\n", __func__, len); + + /* wait for any prerequisite operations */ + async_tx_quiesce(&submit->depend_tx); + + dest_buf = kmap_atomic(dest) + dest_offset; + src_buf = kmap_atomic(src) + src_offset; + + memcpy(dest_buf, src_buf, len); + + kunmap_atomic(src_buf); + kunmap_atomic(dest_buf); + + async_tx_sync_epilog(submit); + } + + dmaengine_unmap_put(unmap); + + return tx; +} +EXPORT_SYMBOL_GPL(async_memcpy); + +MODULE_AUTHOR("Intel Corporation"); +MODULE_DESCRIPTION("asynchronous memcpy api"); +MODULE_LICENSE("GPL"); diff --git a/kernel/crypto/async_tx/async_pq.c b/kernel/crypto/async_tx/async_pq.c new file mode 100644 index 000000000..5d355e0c2 --- /dev/null +++ b/kernel/crypto/async_tx/async_pq.c @@ -0,0 +1,454 @@ +/* + * Copyright(c) 2007 Yuri Tikhonov <yur@emcraft.com> + * Copyright(c) 2009 Intel Corporation + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by the Free + * Software Foundation; either version 2 of the License, or (at your option) + * any later version. + * + * This program is distributed in the hope that it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + * + * You should have received a copy of the GNU General Public License along with + * this program; if not, write to the Free Software Foundation, Inc., 59 + * Temple Place - Suite 330, Boston, MA 02111-1307, USA. + * + * The full GNU General Public License is included in this distribution in the + * file called COPYING. + */ +#include <linux/kernel.h> +#include <linux/interrupt.h> +#include <linux/module.h> +#include <linux/dma-mapping.h> +#include <linux/raid/pq.h> +#include <linux/async_tx.h> +#include <linux/gfp.h> + +/** + * pq_scribble_page - space to hold throwaway P or Q buffer for + * synchronous gen_syndrome + */ +static struct page *pq_scribble_page; + +/* the struct page *blocks[] parameter passed to async_gen_syndrome() + * and async_syndrome_val() contains the 'P' destination address at + * blocks[disks-2] and the 'Q' destination address at blocks[disks-1] + * + * note: these are macros as they are used as lvalues + */ +#define P(b, d) (b[d-2]) +#define Q(b, d) (b[d-1]) + +/** + * do_async_gen_syndrome - asynchronously calculate P and/or Q + */ +static __async_inline struct dma_async_tx_descriptor * +do_async_gen_syndrome(struct dma_chan *chan, + const unsigned char *scfs, int disks, + struct dmaengine_unmap_data *unmap, + enum dma_ctrl_flags dma_flags, + struct async_submit_ctl *submit) +{ + struct dma_async_tx_descriptor *tx = NULL; + struct dma_device *dma = chan->device; + enum async_tx_flags flags_orig = submit->flags; + dma_async_tx_callback cb_fn_orig = submit->cb_fn; + dma_async_tx_callback cb_param_orig = submit->cb_param; + int src_cnt = disks - 2; + unsigned short pq_src_cnt; + dma_addr_t dma_dest[2]; + int src_off = 0; + + if (submit->flags & ASYNC_TX_FENCE) + dma_flags |= DMA_PREP_FENCE; + + while (src_cnt > 0) { + submit->flags = flags_orig; + pq_src_cnt = min(src_cnt, dma_maxpq(dma, dma_flags)); + /* if we are submitting additional pqs, leave the chain open, + * clear the callback parameters, and leave the destination + * buffers mapped + */ + if (src_cnt > pq_src_cnt) { + submit->flags &= ~ASYNC_TX_ACK; + submit->flags |= ASYNC_TX_FENCE; + submit->cb_fn = NULL; + submit->cb_param = NULL; + } else { + submit->cb_fn = cb_fn_orig; + submit->cb_param = cb_param_orig; + if (cb_fn_orig) + dma_flags |= DMA_PREP_INTERRUPT; + } + + /* Drivers force forward progress in case they can not provide + * a descriptor + */ + for (;;) { + dma_dest[0] = unmap->addr[disks - 2]; + dma_dest[1] = unmap->addr[disks - 1]; + tx = dma->device_prep_dma_pq(chan, dma_dest, + &unmap->addr[src_off], + pq_src_cnt, + &scfs[src_off], unmap->len, + dma_flags); + if (likely(tx)) + break; + async_tx_quiesce(&submit->depend_tx); + dma_async_issue_pending(chan); + } + + dma_set_unmap(tx, unmap); + async_tx_submit(chan, tx, submit); + submit->depend_tx = tx; + + /* drop completed sources */ + src_cnt -= pq_src_cnt; + src_off += pq_src_cnt; + + dma_flags |= DMA_PREP_CONTINUE; + } + + return tx; +} + +/** + * do_sync_gen_syndrome - synchronously calculate a raid6 syndrome + */ +static void +do_sync_gen_syndrome(struct page **blocks, unsigned int offset, int disks, + size_t len, struct async_submit_ctl *submit) +{ + void **srcs; + int i; + int start = -1, stop = disks - 3; + + if (submit->scribble) + srcs = submit->scribble; + else + srcs = (void **) blocks; + + for (i = 0; i < disks; i++) { + if (blocks[i] == NULL) { + BUG_ON(i > disks - 3); /* P or Q can't be zero */ + srcs[i] = (void*)raid6_empty_zero_page; + } else { + srcs[i] = page_address(blocks[i]) + offset; + if (i < disks - 2) { + stop = i; + if (start == -1) + start = i; + } + } + } + if (submit->flags & ASYNC_TX_PQ_XOR_DST) { + BUG_ON(!raid6_call.xor_syndrome); + if (start >= 0) + raid6_call.xor_syndrome(disks, start, stop, len, srcs); + } else + raid6_call.gen_syndrome(disks, len, srcs); + async_tx_sync_epilog(submit); +} + +/** + * async_gen_syndrome - asynchronously calculate a raid6 syndrome + * @blocks: source blocks from idx 0..disks-3, P @ disks-2 and Q @ disks-1 + * @offset: common offset into each block (src and dest) to start transaction + * @disks: number of blocks (including missing P or Q, see below) + * @len: length of operation in bytes + * @submit: submission/completion modifiers + * + * General note: This routine assumes a field of GF(2^8) with a + * primitive polynomial of 0x11d and a generator of {02}. + * + * 'disks' note: callers can optionally omit either P or Q (but not + * both) from the calculation by setting blocks[disks-2] or + * blocks[disks-1] to NULL. When P or Q is omitted 'len' must be <= + * PAGE_SIZE as a temporary buffer of this size is used in the + * synchronous path. 'disks' always accounts for both destination + * buffers. If any source buffers (blocks[i] where i < disks - 2) are + * set to NULL those buffers will be replaced with the raid6_zero_page + * in the synchronous path and omitted in the hardware-asynchronous + * path. + */ +struct dma_async_tx_descriptor * +async_gen_syndrome(struct page **blocks, unsigned int offset, int disks, + size_t len, struct async_submit_ctl *submit) +{ + int src_cnt = disks - 2; + struct dma_chan *chan = async_tx_find_channel(submit, DMA_PQ, + &P(blocks, disks), 2, + blocks, src_cnt, len); + struct dma_device *device = chan ? chan->device : NULL; + struct dmaengine_unmap_data *unmap = NULL; + + BUG_ON(disks > 255 || !(P(blocks, disks) || Q(blocks, disks))); + + if (device) + unmap = dmaengine_get_unmap_data(device->dev, disks, GFP_NOIO); + + /* XORing P/Q is only implemented in software */ + if (unmap && !(submit->flags & ASYNC_TX_PQ_XOR_DST) && + (src_cnt <= dma_maxpq(device, 0) || + dma_maxpq(device, DMA_PREP_CONTINUE) > 0) && + is_dma_pq_aligned(device, offset, 0, len)) { + struct dma_async_tx_descriptor *tx; + enum dma_ctrl_flags dma_flags = 0; + unsigned char coefs[src_cnt]; + int i, j; + + /* run the p+q asynchronously */ + pr_debug("%s: (async) disks: %d len: %zu\n", + __func__, disks, len); + + /* convert source addresses being careful to collapse 'empty' + * sources and update the coefficients accordingly + */ + unmap->len = len; + for (i = 0, j = 0; i < src_cnt; i++) { + if (blocks[i] == NULL) + continue; + unmap->addr[j] = dma_map_page(device->dev, blocks[i], offset, + len, DMA_TO_DEVICE); + coefs[j] = raid6_gfexp[i]; + unmap->to_cnt++; + j++; + } + + /* + * DMAs use destinations as sources, + * so use BIDIRECTIONAL mapping + */ + unmap->bidi_cnt++; + if (P(blocks, disks)) + unmap->addr[j++] = dma_map_page(device->dev, P(blocks, disks), + offset, len, DMA_BIDIRECTIONAL); + else { + unmap->addr[j++] = 0; + dma_flags |= DMA_PREP_PQ_DISABLE_P; + } + + unmap->bidi_cnt++; + if (Q(blocks, disks)) + unmap->addr[j++] = dma_map_page(device->dev, Q(blocks, disks), + offset, len, DMA_BIDIRECTIONAL); + else { + unmap->addr[j++] = 0; + dma_flags |= DMA_PREP_PQ_DISABLE_Q; + } + + tx = do_async_gen_syndrome(chan, coefs, j, unmap, dma_flags, submit); + dmaengine_unmap_put(unmap); + return tx; + } + + dmaengine_unmap_put(unmap); + + /* run the pq synchronously */ + pr_debug("%s: (sync) disks: %d len: %zu\n", __func__, disks, len); + + /* wait for any prerequisite operations */ + async_tx_quiesce(&submit->depend_tx); + + if (!P(blocks, disks)) { + P(blocks, disks) = pq_scribble_page; + BUG_ON(len + offset > PAGE_SIZE); + } + if (!Q(blocks, disks)) { + Q(blocks, disks) = pq_scribble_page; + BUG_ON(len + offset > PAGE_SIZE); + } + do_sync_gen_syndrome(blocks, offset, disks, len, submit); + + return NULL; +} +EXPORT_SYMBOL_GPL(async_gen_syndrome); + +static inline struct dma_chan * +pq_val_chan(struct async_submit_ctl *submit, struct page **blocks, int disks, size_t len) +{ + #ifdef CONFIG_ASYNC_TX_DISABLE_PQ_VAL_DMA + return NULL; + #endif + return async_tx_find_channel(submit, DMA_PQ_VAL, NULL, 0, blocks, + disks, len); +} + +/** + * async_syndrome_val - asynchronously validate a raid6 syndrome + * @blocks: source blocks from idx 0..disks-3, P @ disks-2 and Q @ disks-1 + * @offset: common offset into each block (src and dest) to start transaction + * @disks: number of blocks (including missing P or Q, see below) + * @len: length of operation in bytes + * @pqres: on val failure SUM_CHECK_P_RESULT and/or SUM_CHECK_Q_RESULT are set + * @spare: temporary result buffer for the synchronous case + * @submit: submission / completion modifiers + * + * The same notes from async_gen_syndrome apply to the 'blocks', + * and 'disks' parameters of this routine. The synchronous path + * requires a temporary result buffer and submit->scribble to be + * specified. + */ +struct dma_async_tx_descriptor * +async_syndrome_val(struct page **blocks, unsigned int offset, int disks, + size_t len, enum sum_check_flags *pqres, struct page *spare, + struct async_submit_ctl *submit) +{ + struct dma_chan *chan = pq_val_chan(submit, blocks, disks, len); + struct dma_device *device = chan ? chan->device : NULL; + struct dma_async_tx_descriptor *tx; + unsigned char coefs[disks-2]; + enum dma_ctrl_flags dma_flags = submit->cb_fn ? DMA_PREP_INTERRUPT : 0; + struct dmaengine_unmap_data *unmap = NULL; + + BUG_ON(disks < 4); + + if (device) + unmap = dmaengine_get_unmap_data(device->dev, disks, GFP_NOIO); + + if (unmap && disks <= dma_maxpq(device, 0) && + is_dma_pq_aligned(device, offset, 0, len)) { + struct device *dev = device->dev; + dma_addr_t pq[2]; + int i, j = 0, src_cnt = 0; + + pr_debug("%s: (async) disks: %d len: %zu\n", + __func__, disks, len); + + unmap->len = len; + for (i = 0; i < disks-2; i++) + if (likely(blocks[i])) { + unmap->addr[j] = dma_map_page(dev, blocks[i], + offset, len, + DMA_TO_DEVICE); + coefs[j] = raid6_gfexp[i]; + unmap->to_cnt++; + src_cnt++; + j++; + } + + if (!P(blocks, disks)) { + pq[0] = 0; + dma_flags |= DMA_PREP_PQ_DISABLE_P; + } else { + pq[0] = dma_map_page(dev, P(blocks, disks), + offset, len, + DMA_TO_DEVICE); + unmap->addr[j++] = pq[0]; + unmap->to_cnt++; + } + if (!Q(blocks, disks)) { + pq[1] = 0; + dma_flags |= DMA_PREP_PQ_DISABLE_Q; + } else { + pq[1] = dma_map_page(dev, Q(blocks, disks), + offset, len, + DMA_TO_DEVICE); + unmap->addr[j++] = pq[1]; + unmap->to_cnt++; + } + + if (submit->flags & ASYNC_TX_FENCE) + dma_flags |= DMA_PREP_FENCE; + for (;;) { + tx = device->device_prep_dma_pq_val(chan, pq, + unmap->addr, + src_cnt, + coefs, + len, pqres, + dma_flags); + if (likely(tx)) + break; + async_tx_quiesce(&submit->depend_tx); + dma_async_issue_pending(chan); + } + + dma_set_unmap(tx, unmap); + async_tx_submit(chan, tx, submit); + + return tx; + } else { + struct page *p_src = P(blocks, disks); + struct page *q_src = Q(blocks, disks); + enum async_tx_flags flags_orig = submit->flags; + dma_async_tx_callback cb_fn_orig = submit->cb_fn; + void *scribble = submit->scribble; + void *cb_param_orig = submit->cb_param; + void *p, *q, *s; + + pr_debug("%s: (sync) disks: %d len: %zu\n", + __func__, disks, len); + + /* caller must provide a temporary result buffer and + * allow the input parameters to be preserved + */ + BUG_ON(!spare || !scribble); + + /* wait for any prerequisite operations */ + async_tx_quiesce(&submit->depend_tx); + + /* recompute p and/or q into the temporary buffer and then + * check to see the result matches the current value + */ + tx = NULL; + *pqres = 0; + if (p_src) { + init_async_submit(submit, ASYNC_TX_XOR_ZERO_DST, NULL, + NULL, NULL, scribble); + tx = async_xor(spare, blocks, offset, disks-2, len, submit); + async_tx_quiesce(&tx); + p = page_address(p_src) + offset; + s = page_address(spare) + offset; + *pqres |= !!memcmp(p, s, len) << SUM_CHECK_P; + } + + if (q_src) { + P(blocks, disks) = NULL; + Q(blocks, disks) = spare; + init_async_submit(submit, 0, NULL, NULL, NULL, scribble); + tx = async_gen_syndrome(blocks, offset, disks, len, submit); + async_tx_quiesce(&tx); + q = page_address(q_src) + offset; + s = page_address(spare) + offset; + *pqres |= !!memcmp(q, s, len) << SUM_CHECK_Q; + } + + /* restore P, Q and submit */ + P(blocks, disks) = p_src; + Q(blocks, disks) = q_src; + + submit->cb_fn = cb_fn_orig; + submit->cb_param = cb_param_orig; + submit->flags = flags_orig; + async_tx_sync_epilog(submit); + + return NULL; + } +} +EXPORT_SYMBOL_GPL(async_syndrome_val); + +static int __init async_pq_init(void) +{ + pq_scribble_page = alloc_page(GFP_KERNEL); + + if (pq_scribble_page) + return 0; + + pr_err("%s: failed to allocate required spare page\n", __func__); + + return -ENOMEM; +} + +static void __exit async_pq_exit(void) +{ + put_page(pq_scribble_page); +} + +module_init(async_pq_init); +module_exit(async_pq_exit); + +MODULE_DESCRIPTION("asynchronous raid6 syndrome generation/validation"); +MODULE_LICENSE("GPL"); diff --git a/kernel/crypto/async_tx/async_raid6_recov.c b/kernel/crypto/async_tx/async_raid6_recov.c new file mode 100644 index 000000000..934a84981 --- /dev/null +++ b/kernel/crypto/async_tx/async_raid6_recov.c @@ -0,0 +1,531 @@ +/* + * Asynchronous RAID-6 recovery calculations ASYNC_TX API. + * Copyright(c) 2009 Intel Corporation + * + * based on raid6recov.c: + * Copyright 2002 H. Peter Anvin + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by the Free + * Software Foundation; either version 2 of the License, or (at your option) + * any later version. + * + * This program is distributed in the hope that it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + * + * You should have received a copy of the GNU General Public License along with + * this program; if not, write to the Free Software Foundation, Inc., 51 + * Franklin St - Fifth Floor, Boston, MA 02110-1301 USA. + * + */ +#include <linux/kernel.h> +#include <linux/interrupt.h> +#include <linux/module.h> +#include <linux/dma-mapping.h> +#include <linux/raid/pq.h> +#include <linux/async_tx.h> +#include <linux/dmaengine.h> + +static struct dma_async_tx_descriptor * +async_sum_product(struct page *dest, struct page **srcs, unsigned char *coef, + size_t len, struct async_submit_ctl *submit) +{ + struct dma_chan *chan = async_tx_find_channel(submit, DMA_PQ, + &dest, 1, srcs, 2, len); + struct dma_device *dma = chan ? chan->device : NULL; + struct dmaengine_unmap_data *unmap = NULL; + const u8 *amul, *bmul; + u8 ax, bx; + u8 *a, *b, *c; + + if (dma) + unmap = dmaengine_get_unmap_data(dma->dev, 3, GFP_NOIO); + + if (unmap) { + struct device *dev = dma->dev; + dma_addr_t pq[2]; + struct dma_async_tx_descriptor *tx; + enum dma_ctrl_flags dma_flags = DMA_PREP_PQ_DISABLE_P; + + if (submit->flags & ASYNC_TX_FENCE) + dma_flags |= DMA_PREP_FENCE; + unmap->addr[0] = dma_map_page(dev, srcs[0], 0, len, DMA_TO_DEVICE); + unmap->addr[1] = dma_map_page(dev, srcs[1], 0, len, DMA_TO_DEVICE); + unmap->to_cnt = 2; + + unmap->addr[2] = dma_map_page(dev, dest, 0, len, DMA_BIDIRECTIONAL); + unmap->bidi_cnt = 1; + /* engine only looks at Q, but expects it to follow P */ + pq[1] = unmap->addr[2]; + + unmap->len = len; + tx = dma->device_prep_dma_pq(chan, pq, unmap->addr, 2, coef, + len, dma_flags); + if (tx) { + dma_set_unmap(tx, unmap); + async_tx_submit(chan, tx, submit); + dmaengine_unmap_put(unmap); + return tx; + } + + /* could not get a descriptor, unmap and fall through to + * the synchronous path + */ + dmaengine_unmap_put(unmap); + } + + /* run the operation synchronously */ + async_tx_quiesce(&submit->depend_tx); + amul = raid6_gfmul[coef[0]]; + bmul = raid6_gfmul[coef[1]]; + a = page_address(srcs[0]); + b = page_address(srcs[1]); + c = page_address(dest); + + while (len--) { + ax = amul[*a++]; + bx = bmul[*b++]; + *c++ = ax ^ bx; + } + + return NULL; +} + +static struct dma_async_tx_descriptor * +async_mult(struct page *dest, struct page *src, u8 coef, size_t len, + struct async_submit_ctl *submit) +{ + struct dma_chan *chan = async_tx_find_channel(submit, DMA_PQ, + &dest, 1, &src, 1, len); + struct dma_device *dma = chan ? chan->device : NULL; + struct dmaengine_unmap_data *unmap = NULL; + const u8 *qmul; /* Q multiplier table */ + u8 *d, *s; + + if (dma) + unmap = dmaengine_get_unmap_data(dma->dev, 3, GFP_NOIO); + + if (unmap) { + dma_addr_t dma_dest[2]; + struct device *dev = dma->dev; + struct dma_async_tx_descriptor *tx; + enum dma_ctrl_flags dma_flags = DMA_PREP_PQ_DISABLE_P; + + if (submit->flags & ASYNC_TX_FENCE) + dma_flags |= DMA_PREP_FENCE; + unmap->addr[0] = dma_map_page(dev, src, 0, len, DMA_TO_DEVICE); + unmap->to_cnt++; + unmap->addr[1] = dma_map_page(dev, dest, 0, len, DMA_BIDIRECTIONAL); + dma_dest[1] = unmap->addr[1]; + unmap->bidi_cnt++; + unmap->len = len; + + /* this looks funny, but the engine looks for Q at + * dma_dest[1] and ignores dma_dest[0] as a dest + * due to DMA_PREP_PQ_DISABLE_P + */ + tx = dma->device_prep_dma_pq(chan, dma_dest, unmap->addr, + 1, &coef, len, dma_flags); + + if (tx) { + dma_set_unmap(tx, unmap); + dmaengine_unmap_put(unmap); + async_tx_submit(chan, tx, submit); + return tx; + } + + /* could not get a descriptor, unmap and fall through to + * the synchronous path + */ + dmaengine_unmap_put(unmap); + } + + /* no channel available, or failed to allocate a descriptor, so + * perform the operation synchronously + */ + async_tx_quiesce(&submit->depend_tx); + qmul = raid6_gfmul[coef]; + d = page_address(dest); + s = page_address(src); + + while (len--) + *d++ = qmul[*s++]; + + return NULL; +} + +static struct dma_async_tx_descriptor * +__2data_recov_4(int disks, size_t bytes, int faila, int failb, + struct page **blocks, struct async_submit_ctl *submit) +{ + struct dma_async_tx_descriptor *tx = NULL; + struct page *p, *q, *a, *b; + struct page *srcs[2]; + unsigned char coef[2]; + enum async_tx_flags flags = submit->flags; + dma_async_tx_callback cb_fn = submit->cb_fn; + void *cb_param = submit->cb_param; + void *scribble = submit->scribble; + + p = blocks[disks-2]; + q = blocks[disks-1]; + + a = blocks[faila]; + b = blocks[failb]; + + /* in the 4 disk case P + Pxy == P and Q + Qxy == Q */ + /* Dx = A*(P+Pxy) + B*(Q+Qxy) */ + srcs[0] = p; + srcs[1] = q; + coef[0] = raid6_gfexi[failb-faila]; + coef[1] = raid6_gfinv[raid6_gfexp[faila]^raid6_gfexp[failb]]; + init_async_submit(submit, ASYNC_TX_FENCE, tx, NULL, NULL, scribble); + tx = async_sum_product(b, srcs, coef, bytes, submit); + + /* Dy = P+Pxy+Dx */ + srcs[0] = p; + srcs[1] = b; + init_async_submit(submit, flags | ASYNC_TX_XOR_ZERO_DST, tx, cb_fn, + cb_param, scribble); + tx = async_xor(a, srcs, 0, 2, bytes, submit); + + return tx; + +} + +static struct dma_async_tx_descriptor * +__2data_recov_5(int disks, size_t bytes, int faila, int failb, + struct page **blocks, struct async_submit_ctl *submit) +{ + struct dma_async_tx_descriptor *tx = NULL; + struct page *p, *q, *g, *dp, *dq; + struct page *srcs[2]; + unsigned char coef[2]; + enum async_tx_flags flags = submit->flags; + dma_async_tx_callback cb_fn = submit->cb_fn; + void *cb_param = submit->cb_param; + void *scribble = submit->scribble; + int good_srcs, good, i; + + good_srcs = 0; + good = -1; + for (i = 0; i < disks-2; i++) { + if (blocks[i] == NULL) + continue; + if (i == faila || i == failb) + continue; + good = i; + good_srcs++; + } + BUG_ON(good_srcs > 1); + + p = blocks[disks-2]; + q = blocks[disks-1]; + g = blocks[good]; + + /* Compute syndrome with zero for the missing data pages + * Use the dead data pages as temporary storage for delta p and + * delta q + */ + dp = blocks[faila]; + dq = blocks[failb]; + + init_async_submit(submit, ASYNC_TX_FENCE, tx, NULL, NULL, scribble); + tx = async_memcpy(dp, g, 0, 0, bytes, submit); + init_async_submit(submit, ASYNC_TX_FENCE, tx, NULL, NULL, scribble); + tx = async_mult(dq, g, raid6_gfexp[good], bytes, submit); + + /* compute P + Pxy */ + srcs[0] = dp; + srcs[1] = p; + init_async_submit(submit, ASYNC_TX_FENCE|ASYNC_TX_XOR_DROP_DST, tx, + NULL, NULL, scribble); + tx = async_xor(dp, srcs, 0, 2, bytes, submit); + + /* compute Q + Qxy */ + srcs[0] = dq; + srcs[1] = q; + init_async_submit(submit, ASYNC_TX_FENCE|ASYNC_TX_XOR_DROP_DST, tx, + NULL, NULL, scribble); + tx = async_xor(dq, srcs, 0, 2, bytes, submit); + + /* Dx = A*(P+Pxy) + B*(Q+Qxy) */ + srcs[0] = dp; + srcs[1] = dq; + coef[0] = raid6_gfexi[failb-faila]; + coef[1] = raid6_gfinv[raid6_gfexp[faila]^raid6_gfexp[failb]]; + init_async_submit(submit, ASYNC_TX_FENCE, tx, NULL, NULL, scribble); + tx = async_sum_product(dq, srcs, coef, bytes, submit); + + /* Dy = P+Pxy+Dx */ + srcs[0] = dp; + srcs[1] = dq; + init_async_submit(submit, flags | ASYNC_TX_XOR_DROP_DST, tx, cb_fn, + cb_param, scribble); + tx = async_xor(dp, srcs, 0, 2, bytes, submit); + + return tx; +} + +static struct dma_async_tx_descriptor * +__2data_recov_n(int disks, size_t bytes, int faila, int failb, + struct page **blocks, struct async_submit_ctl *submit) +{ + struct dma_async_tx_descriptor *tx = NULL; + struct page *p, *q, *dp, *dq; + struct page *srcs[2]; + unsigned char coef[2]; + enum async_tx_flags flags = submit->flags; + dma_async_tx_callback cb_fn = submit->cb_fn; + void *cb_param = submit->cb_param; + void *scribble = submit->scribble; + + p = blocks[disks-2]; + q = blocks[disks-1]; + + /* Compute syndrome with zero for the missing data pages + * Use the dead data pages as temporary storage for + * delta p and delta q + */ + dp = blocks[faila]; + blocks[faila] = NULL; + blocks[disks-2] = dp; + dq = blocks[failb]; + blocks[failb] = NULL; + blocks[disks-1] = dq; + + init_async_submit(submit, ASYNC_TX_FENCE, tx, NULL, NULL, scribble); + tx = async_gen_syndrome(blocks, 0, disks, bytes, submit); + + /* Restore pointer table */ + blocks[faila] = dp; + blocks[failb] = dq; + blocks[disks-2] = p; + blocks[disks-1] = q; + + /* compute P + Pxy */ + srcs[0] = dp; + srcs[1] = p; + init_async_submit(submit, ASYNC_TX_FENCE|ASYNC_TX_XOR_DROP_DST, tx, + NULL, NULL, scribble); + tx = async_xor(dp, srcs, 0, 2, bytes, submit); + + /* compute Q + Qxy */ + srcs[0] = dq; + srcs[1] = q; + init_async_submit(submit, ASYNC_TX_FENCE|ASYNC_TX_XOR_DROP_DST, tx, + NULL, NULL, scribble); + tx = async_xor(dq, srcs, 0, 2, bytes, submit); + + /* Dx = A*(P+Pxy) + B*(Q+Qxy) */ + srcs[0] = dp; + srcs[1] = dq; + coef[0] = raid6_gfexi[failb-faila]; + coef[1] = raid6_gfinv[raid6_gfexp[faila]^raid6_gfexp[failb]]; + init_async_submit(submit, ASYNC_TX_FENCE, tx, NULL, NULL, scribble); + tx = async_sum_product(dq, srcs, coef, bytes, submit); + + /* Dy = P+Pxy+Dx */ + srcs[0] = dp; + srcs[1] = dq; + init_async_submit(submit, flags | ASYNC_TX_XOR_DROP_DST, tx, cb_fn, + cb_param, scribble); + tx = async_xor(dp, srcs, 0, 2, bytes, submit); + + return tx; +} + +/** + * async_raid6_2data_recov - asynchronously calculate two missing data blocks + * @disks: number of disks in the RAID-6 array + * @bytes: block size + * @faila: first failed drive index + * @failb: second failed drive index + * @blocks: array of source pointers where the last two entries are p and q + * @submit: submission/completion modifiers + */ +struct dma_async_tx_descriptor * +async_raid6_2data_recov(int disks, size_t bytes, int faila, int failb, + struct page **blocks, struct async_submit_ctl *submit) +{ + void *scribble = submit->scribble; + int non_zero_srcs, i; + + BUG_ON(faila == failb); + if (failb < faila) + swap(faila, failb); + + pr_debug("%s: disks: %d len: %zu\n", __func__, disks, bytes); + + /* if a dma resource is not available or a scribble buffer is not + * available punt to the synchronous path. In the 'dma not + * available' case be sure to use the scribble buffer to + * preserve the content of 'blocks' as the caller intended. + */ + if (!async_dma_find_channel(DMA_PQ) || !scribble) { + void **ptrs = scribble ? scribble : (void **) blocks; + + async_tx_quiesce(&submit->depend_tx); + for (i = 0; i < disks; i++) + if (blocks[i] == NULL) + ptrs[i] = (void *) raid6_empty_zero_page; + else + ptrs[i] = page_address(blocks[i]); + + raid6_2data_recov(disks, bytes, faila, failb, ptrs); + + async_tx_sync_epilog(submit); + + return NULL; + } + + non_zero_srcs = 0; + for (i = 0; i < disks-2 && non_zero_srcs < 4; i++) + if (blocks[i]) + non_zero_srcs++; + switch (non_zero_srcs) { + case 0: + case 1: + /* There must be at least 2 sources - the failed devices. */ + BUG(); + + case 2: + /* dma devices do not uniformly understand a zero source pq + * operation (in contrast to the synchronous case), so + * explicitly handle the special case of a 4 disk array with + * both data disks missing. + */ + return __2data_recov_4(disks, bytes, faila, failb, blocks, submit); + case 3: + /* dma devices do not uniformly understand a single + * source pq operation (in contrast to the synchronous + * case), so explicitly handle the special case of a 5 disk + * array with 2 of 3 data disks missing. + */ + return __2data_recov_5(disks, bytes, faila, failb, blocks, submit); + default: + return __2data_recov_n(disks, bytes, faila, failb, blocks, submit); + } +} +EXPORT_SYMBOL_GPL(async_raid6_2data_recov); + +/** + * async_raid6_datap_recov - asynchronously calculate a data and the 'p' block + * @disks: number of disks in the RAID-6 array + * @bytes: block size + * @faila: failed drive index + * @blocks: array of source pointers where the last two entries are p and q + * @submit: submission/completion modifiers + */ +struct dma_async_tx_descriptor * +async_raid6_datap_recov(int disks, size_t bytes, int faila, + struct page **blocks, struct async_submit_ctl *submit) +{ + struct dma_async_tx_descriptor *tx = NULL; + struct page *p, *q, *dq; + u8 coef; + enum async_tx_flags flags = submit->flags; + dma_async_tx_callback cb_fn = submit->cb_fn; + void *cb_param = submit->cb_param; + void *scribble = submit->scribble; + int good_srcs, good, i; + struct page *srcs[2]; + + pr_debug("%s: disks: %d len: %zu\n", __func__, disks, bytes); + + /* if a dma resource is not available or a scribble buffer is not + * available punt to the synchronous path. In the 'dma not + * available' case be sure to use the scribble buffer to + * preserve the content of 'blocks' as the caller intended. + */ + if (!async_dma_find_channel(DMA_PQ) || !scribble) { + void **ptrs = scribble ? scribble : (void **) blocks; + + async_tx_quiesce(&submit->depend_tx); + for (i = 0; i < disks; i++) + if (blocks[i] == NULL) + ptrs[i] = (void*)raid6_empty_zero_page; + else + ptrs[i] = page_address(blocks[i]); + + raid6_datap_recov(disks, bytes, faila, ptrs); + + async_tx_sync_epilog(submit); + + return NULL; + } + + good_srcs = 0; + good = -1; + for (i = 0; i < disks-2; i++) { + if (i == faila) + continue; + if (blocks[i]) { + good = i; + good_srcs++; + if (good_srcs > 1) + break; + } + } + BUG_ON(good_srcs == 0); + + p = blocks[disks-2]; + q = blocks[disks-1]; + + /* Compute syndrome with zero for the missing data page + * Use the dead data page as temporary storage for delta q + */ + dq = blocks[faila]; + blocks[faila] = NULL; + blocks[disks-1] = dq; + + /* in the 4-disk case we only need to perform a single source + * multiplication with the one good data block. + */ + if (good_srcs == 1) { + struct page *g = blocks[good]; + + init_async_submit(submit, ASYNC_TX_FENCE, tx, NULL, NULL, + scribble); + tx = async_memcpy(p, g, 0, 0, bytes, submit); + + init_async_submit(submit, ASYNC_TX_FENCE, tx, NULL, NULL, + scribble); + tx = async_mult(dq, g, raid6_gfexp[good], bytes, submit); + } else { + init_async_submit(submit, ASYNC_TX_FENCE, tx, NULL, NULL, + scribble); + tx = async_gen_syndrome(blocks, 0, disks, bytes, submit); + } + + /* Restore pointer table */ + blocks[faila] = dq; + blocks[disks-1] = q; + + /* calculate g^{-faila} */ + coef = raid6_gfinv[raid6_gfexp[faila]]; + + srcs[0] = dq; + srcs[1] = q; + init_async_submit(submit, ASYNC_TX_FENCE|ASYNC_TX_XOR_DROP_DST, tx, + NULL, NULL, scribble); + tx = async_xor(dq, srcs, 0, 2, bytes, submit); + + init_async_submit(submit, ASYNC_TX_FENCE, tx, NULL, NULL, scribble); + tx = async_mult(dq, dq, coef, bytes, submit); + + srcs[0] = p; + srcs[1] = dq; + init_async_submit(submit, flags | ASYNC_TX_XOR_DROP_DST, tx, cb_fn, + cb_param, scribble); + tx = async_xor(p, srcs, 0, 2, bytes, submit); + + return tx; +} +EXPORT_SYMBOL_GPL(async_raid6_datap_recov); + +MODULE_AUTHOR("Dan Williams <dan.j.williams@intel.com>"); +MODULE_DESCRIPTION("asynchronous RAID-6 recovery api"); +MODULE_LICENSE("GPL"); diff --git a/kernel/crypto/async_tx/async_tx.c b/kernel/crypto/async_tx/async_tx.c new file mode 100644 index 000000000..39ea4791a --- /dev/null +++ b/kernel/crypto/async_tx/async_tx.c @@ -0,0 +1,294 @@ +/* + * core routines for the asynchronous memory transfer/transform api + * + * Copyright © 2006, Intel Corporation. + * + * Dan Williams <dan.j.williams@intel.com> + * + * with architecture considerations by: + * Neil Brown <neilb@suse.de> + * Jeff Garzik <jeff@garzik.org> + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions of the GNU General Public License, + * version 2, as published by the Free Software Foundation. + * + * This program is distributed in the hope it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + * + * You should have received a copy of the GNU General Public License along with + * this program; if not, write to the Free Software Foundation, Inc., + * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA. + * + */ +#include <linux/rculist.h> +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/async_tx.h> + +#ifdef CONFIG_DMA_ENGINE +static int __init async_tx_init(void) +{ + async_dmaengine_get(); + + printk(KERN_INFO "async_tx: api initialized (async)\n"); + + return 0; +} + +static void __exit async_tx_exit(void) +{ + async_dmaengine_put(); +} + +module_init(async_tx_init); +module_exit(async_tx_exit); + +/** + * __async_tx_find_channel - find a channel to carry out the operation or let + * the transaction execute synchronously + * @submit: transaction dependency and submission modifiers + * @tx_type: transaction type + */ +struct dma_chan * +__async_tx_find_channel(struct async_submit_ctl *submit, + enum dma_transaction_type tx_type) +{ + struct dma_async_tx_descriptor *depend_tx = submit->depend_tx; + + /* see if we can keep the chain on one channel */ + if (depend_tx && + dma_has_cap(tx_type, depend_tx->chan->device->cap_mask)) + return depend_tx->chan; + return async_dma_find_channel(tx_type); +} +EXPORT_SYMBOL_GPL(__async_tx_find_channel); +#endif + + +/** + * async_tx_channel_switch - queue an interrupt descriptor with a dependency + * pre-attached. + * @depend_tx: the operation that must finish before the new operation runs + * @tx: the new operation + */ +static void +async_tx_channel_switch(struct dma_async_tx_descriptor *depend_tx, + struct dma_async_tx_descriptor *tx) +{ + struct dma_chan *chan = depend_tx->chan; + struct dma_device *device = chan->device; + struct dma_async_tx_descriptor *intr_tx = (void *) ~0; + + /* first check to see if we can still append to depend_tx */ + txd_lock(depend_tx); + if (txd_parent(depend_tx) && depend_tx->chan == tx->chan) { + txd_chain(depend_tx, tx); + intr_tx = NULL; + } + txd_unlock(depend_tx); + + /* attached dependency, flush the parent channel */ + if (!intr_tx) { + device->device_issue_pending(chan); + return; + } + + /* see if we can schedule an interrupt + * otherwise poll for completion + */ + if (dma_has_cap(DMA_INTERRUPT, device->cap_mask)) + intr_tx = device->device_prep_dma_interrupt(chan, 0); + else + intr_tx = NULL; + + if (intr_tx) { + intr_tx->callback = NULL; + intr_tx->callback_param = NULL; + /* safe to chain outside the lock since we know we are + * not submitted yet + */ + txd_chain(intr_tx, tx); + + /* check if we need to append */ + txd_lock(depend_tx); + if (txd_parent(depend_tx)) { + txd_chain(depend_tx, intr_tx); + async_tx_ack(intr_tx); + intr_tx = NULL; + } + txd_unlock(depend_tx); + + if (intr_tx) { + txd_clear_parent(intr_tx); + intr_tx->tx_submit(intr_tx); + async_tx_ack(intr_tx); + } + device->device_issue_pending(chan); + } else { + if (dma_wait_for_async_tx(depend_tx) != DMA_COMPLETE) + panic("%s: DMA error waiting for depend_tx\n", + __func__); + tx->tx_submit(tx); + } +} + + +/** + * submit_disposition - flags for routing an incoming operation + * @ASYNC_TX_SUBMITTED: we were able to append the new operation under the lock + * @ASYNC_TX_CHANNEL_SWITCH: when the lock is dropped schedule a channel switch + * @ASYNC_TX_DIRECT_SUBMIT: when the lock is dropped submit directly + * + * while holding depend_tx->lock we must avoid submitting new operations + * to prevent a circular locking dependency with drivers that already + * hold a channel lock when calling async_tx_run_dependencies. + */ +enum submit_disposition { + ASYNC_TX_SUBMITTED, + ASYNC_TX_CHANNEL_SWITCH, + ASYNC_TX_DIRECT_SUBMIT, +}; + +void +async_tx_submit(struct dma_chan *chan, struct dma_async_tx_descriptor *tx, + struct async_submit_ctl *submit) +{ + struct dma_async_tx_descriptor *depend_tx = submit->depend_tx; + + tx->callback = submit->cb_fn; + tx->callback_param = submit->cb_param; + + if (depend_tx) { + enum submit_disposition s; + + /* sanity check the dependency chain: + * 1/ if ack is already set then we cannot be sure + * we are referring to the correct operation + * 2/ dependencies are 1:1 i.e. two transactions can + * not depend on the same parent + */ + BUG_ON(async_tx_test_ack(depend_tx) || txd_next(depend_tx) || + txd_parent(tx)); + + /* the lock prevents async_tx_run_dependencies from missing + * the setting of ->next when ->parent != NULL + */ + txd_lock(depend_tx); + if (txd_parent(depend_tx)) { + /* we have a parent so we can not submit directly + * if we are staying on the same channel: append + * else: channel switch + */ + if (depend_tx->chan == chan) { + txd_chain(depend_tx, tx); + s = ASYNC_TX_SUBMITTED; + } else + s = ASYNC_TX_CHANNEL_SWITCH; + } else { + /* we do not have a parent so we may be able to submit + * directly if we are staying on the same channel + */ + if (depend_tx->chan == chan) + s = ASYNC_TX_DIRECT_SUBMIT; + else + s = ASYNC_TX_CHANNEL_SWITCH; + } + txd_unlock(depend_tx); + + switch (s) { + case ASYNC_TX_SUBMITTED: + break; + case ASYNC_TX_CHANNEL_SWITCH: + async_tx_channel_switch(depend_tx, tx); + break; + case ASYNC_TX_DIRECT_SUBMIT: + txd_clear_parent(tx); + tx->tx_submit(tx); + break; + } + } else { + txd_clear_parent(tx); + tx->tx_submit(tx); + } + + if (submit->flags & ASYNC_TX_ACK) + async_tx_ack(tx); + + if (depend_tx) + async_tx_ack(depend_tx); +} +EXPORT_SYMBOL_GPL(async_tx_submit); + +/** + * async_trigger_callback - schedules the callback function to be run + * @submit: submission and completion parameters + * + * honored flags: ASYNC_TX_ACK + * + * The callback is run after any dependent operations have completed. + */ +struct dma_async_tx_descriptor * +async_trigger_callback(struct async_submit_ctl *submit) +{ + struct dma_chan *chan; + struct dma_device *device; + struct dma_async_tx_descriptor *tx; + struct dma_async_tx_descriptor *depend_tx = submit->depend_tx; + + if (depend_tx) { + chan = depend_tx->chan; + device = chan->device; + + /* see if we can schedule an interrupt + * otherwise poll for completion + */ + if (device && !dma_has_cap(DMA_INTERRUPT, device->cap_mask)) + device = NULL; + + tx = device ? device->device_prep_dma_interrupt(chan, 0) : NULL; + } else + tx = NULL; + + if (tx) { + pr_debug("%s: (async)\n", __func__); + + async_tx_submit(chan, tx, submit); + } else { + pr_debug("%s: (sync)\n", __func__); + + /* wait for any prerequisite operations */ + async_tx_quiesce(&submit->depend_tx); + + async_tx_sync_epilog(submit); + } + + return tx; +} +EXPORT_SYMBOL_GPL(async_trigger_callback); + +/** + * async_tx_quiesce - ensure tx is complete and freeable upon return + * @tx - transaction to quiesce + */ +void async_tx_quiesce(struct dma_async_tx_descriptor **tx) +{ + if (*tx) { + /* if ack is already set then we cannot be sure + * we are referring to the correct operation + */ + BUG_ON(async_tx_test_ack(*tx)); + if (dma_wait_for_async_tx(*tx) != DMA_COMPLETE) + panic("%s: DMA error waiting for transaction\n", + __func__); + async_tx_ack(*tx); + *tx = NULL; + } +} +EXPORT_SYMBOL_GPL(async_tx_quiesce); + +MODULE_AUTHOR("Intel Corporation"); +MODULE_DESCRIPTION("Asynchronous Bulk Memory Transactions API"); +MODULE_LICENSE("GPL"); diff --git a/kernel/crypto/async_tx/async_xor.c b/kernel/crypto/async_tx/async_xor.c new file mode 100644 index 000000000..e1bce26cd --- /dev/null +++ b/kernel/crypto/async_tx/async_xor.c @@ -0,0 +1,345 @@ +/* + * xor offload engine api + * + * Copyright © 2006, Intel Corporation. + * + * Dan Williams <dan.j.williams@intel.com> + * + * with architecture considerations by: + * Neil Brown <neilb@suse.de> + * Jeff Garzik <jeff@garzik.org> + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions of the GNU General Public License, + * version 2, as published by the Free Software Foundation. + * + * This program is distributed in the hope it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + * + * You should have received a copy of the GNU General Public License along with + * this program; if not, write to the Free Software Foundation, Inc., + * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA. + * + */ +#include <linux/kernel.h> +#include <linux/interrupt.h> +#include <linux/module.h> +#include <linux/mm.h> +#include <linux/dma-mapping.h> +#include <linux/raid/xor.h> +#include <linux/async_tx.h> + +/* do_async_xor - dma map the pages and perform the xor with an engine */ +static __async_inline struct dma_async_tx_descriptor * +do_async_xor(struct dma_chan *chan, struct dmaengine_unmap_data *unmap, + struct async_submit_ctl *submit) +{ + struct dma_device *dma = chan->device; + struct dma_async_tx_descriptor *tx = NULL; + dma_async_tx_callback cb_fn_orig = submit->cb_fn; + void *cb_param_orig = submit->cb_param; + enum async_tx_flags flags_orig = submit->flags; + enum dma_ctrl_flags dma_flags = 0; + int src_cnt = unmap->to_cnt; + int xor_src_cnt; + dma_addr_t dma_dest = unmap->addr[unmap->to_cnt]; + dma_addr_t *src_list = unmap->addr; + + while (src_cnt) { + dma_addr_t tmp; + + submit->flags = flags_orig; + xor_src_cnt = min(src_cnt, (int)dma->max_xor); + /* if we are submitting additional xors, leave the chain open + * and clear the callback parameters + */ + if (src_cnt > xor_src_cnt) { + submit->flags &= ~ASYNC_TX_ACK; + submit->flags |= ASYNC_TX_FENCE; + submit->cb_fn = NULL; + submit->cb_param = NULL; + } else { + submit->cb_fn = cb_fn_orig; + submit->cb_param = cb_param_orig; + } + if (submit->cb_fn) + dma_flags |= DMA_PREP_INTERRUPT; + if (submit->flags & ASYNC_TX_FENCE) + dma_flags |= DMA_PREP_FENCE; + + /* Drivers force forward progress in case they can not provide a + * descriptor + */ + tmp = src_list[0]; + if (src_list > unmap->addr) + src_list[0] = dma_dest; + tx = dma->device_prep_dma_xor(chan, dma_dest, src_list, + xor_src_cnt, unmap->len, + dma_flags); + + if (unlikely(!tx)) + async_tx_quiesce(&submit->depend_tx); + + /* spin wait for the preceding transactions to complete */ + while (unlikely(!tx)) { + dma_async_issue_pending(chan); + tx = dma->device_prep_dma_xor(chan, dma_dest, + src_list, + xor_src_cnt, unmap->len, + dma_flags); + } + src_list[0] = tmp; + + dma_set_unmap(tx, unmap); + async_tx_submit(chan, tx, submit); + submit->depend_tx = tx; + + if (src_cnt > xor_src_cnt) { + /* drop completed sources */ + src_cnt -= xor_src_cnt; + /* use the intermediate result a source */ + src_cnt++; + src_list += xor_src_cnt - 1; + } else + break; + } + + return tx; +} + +static void +do_sync_xor(struct page *dest, struct page **src_list, unsigned int offset, + int src_cnt, size_t len, struct async_submit_ctl *submit) +{ + int i; + int xor_src_cnt = 0; + int src_off = 0; + void *dest_buf; + void **srcs; + + if (submit->scribble) + srcs = submit->scribble; + else + srcs = (void **) src_list; + + /* convert to buffer pointers */ + for (i = 0; i < src_cnt; i++) + if (src_list[i]) + srcs[xor_src_cnt++] = page_address(src_list[i]) + offset; + src_cnt = xor_src_cnt; + /* set destination address */ + dest_buf = page_address(dest) + offset; + + if (submit->flags & ASYNC_TX_XOR_ZERO_DST) + memset(dest_buf, 0, len); + + while (src_cnt > 0) { + /* process up to 'MAX_XOR_BLOCKS' sources */ + xor_src_cnt = min(src_cnt, MAX_XOR_BLOCKS); + xor_blocks(xor_src_cnt, len, dest_buf, &srcs[src_off]); + + /* drop completed sources */ + src_cnt -= xor_src_cnt; + src_off += xor_src_cnt; + } + + async_tx_sync_epilog(submit); +} + +/** + * async_xor - attempt to xor a set of blocks with a dma engine. + * @dest: destination page + * @src_list: array of source pages + * @offset: common src/dst offset to start transaction + * @src_cnt: number of source pages + * @len: length in bytes + * @submit: submission / completion modifiers + * + * honored flags: ASYNC_TX_ACK, ASYNC_TX_XOR_ZERO_DST, ASYNC_TX_XOR_DROP_DST + * + * xor_blocks always uses the dest as a source so the + * ASYNC_TX_XOR_ZERO_DST flag must be set to not include dest data in + * the calculation. The assumption with dma eninges is that they only + * use the destination buffer as a source when it is explicity specified + * in the source list. + * + * src_list note: if the dest is also a source it must be at index zero. + * The contents of this array will be overwritten if a scribble region + * is not specified. + */ +struct dma_async_tx_descriptor * +async_xor(struct page *dest, struct page **src_list, unsigned int offset, + int src_cnt, size_t len, struct async_submit_ctl *submit) +{ + struct dma_chan *chan = async_tx_find_channel(submit, DMA_XOR, + &dest, 1, src_list, + src_cnt, len); + struct dma_device *device = chan ? chan->device : NULL; + struct dmaengine_unmap_data *unmap = NULL; + + BUG_ON(src_cnt <= 1); + + if (device) + unmap = dmaengine_get_unmap_data(device->dev, src_cnt+1, GFP_NOIO); + + if (unmap && is_dma_xor_aligned(device, offset, 0, len)) { + struct dma_async_tx_descriptor *tx; + int i, j; + + /* run the xor asynchronously */ + pr_debug("%s (async): len: %zu\n", __func__, len); + + unmap->len = len; + for (i = 0, j = 0; i < src_cnt; i++) { + if (!src_list[i]) + continue; + unmap->to_cnt++; + unmap->addr[j++] = dma_map_page(device->dev, src_list[i], + offset, len, DMA_TO_DEVICE); + } + + /* map it bidirectional as it may be re-used as a source */ + unmap->addr[j] = dma_map_page(device->dev, dest, offset, len, + DMA_BIDIRECTIONAL); + unmap->bidi_cnt = 1; + + tx = do_async_xor(chan, unmap, submit); + dmaengine_unmap_put(unmap); + return tx; + } else { + dmaengine_unmap_put(unmap); + /* run the xor synchronously */ + pr_debug("%s (sync): len: %zu\n", __func__, len); + WARN_ONCE(chan, "%s: no space for dma address conversion\n", + __func__); + + /* in the sync case the dest is an implied source + * (assumes the dest is the first source) + */ + if (submit->flags & ASYNC_TX_XOR_DROP_DST) { + src_cnt--; + src_list++; + } + + /* wait for any prerequisite operations */ + async_tx_quiesce(&submit->depend_tx); + + do_sync_xor(dest, src_list, offset, src_cnt, len, submit); + + return NULL; + } +} +EXPORT_SYMBOL_GPL(async_xor); + +static int page_is_zero(struct page *p, unsigned int offset, size_t len) +{ + return !memchr_inv(page_address(p) + offset, 0, len); +} + +static inline struct dma_chan * +xor_val_chan(struct async_submit_ctl *submit, struct page *dest, + struct page **src_list, int src_cnt, size_t len) +{ + #ifdef CONFIG_ASYNC_TX_DISABLE_XOR_VAL_DMA + return NULL; + #endif + return async_tx_find_channel(submit, DMA_XOR_VAL, &dest, 1, src_list, + src_cnt, len); +} + +/** + * async_xor_val - attempt a xor parity check with a dma engine. + * @dest: destination page used if the xor is performed synchronously + * @src_list: array of source pages + * @offset: offset in pages to start transaction + * @src_cnt: number of source pages + * @len: length in bytes + * @result: 0 if sum == 0 else non-zero + * @submit: submission / completion modifiers + * + * honored flags: ASYNC_TX_ACK + * + * src_list note: if the dest is also a source it must be at index zero. + * The contents of this array will be overwritten if a scribble region + * is not specified. + */ +struct dma_async_tx_descriptor * +async_xor_val(struct page *dest, struct page **src_list, unsigned int offset, + int src_cnt, size_t len, enum sum_check_flags *result, + struct async_submit_ctl *submit) +{ + struct dma_chan *chan = xor_val_chan(submit, dest, src_list, src_cnt, len); + struct dma_device *device = chan ? chan->device : NULL; + struct dma_async_tx_descriptor *tx = NULL; + struct dmaengine_unmap_data *unmap = NULL; + + BUG_ON(src_cnt <= 1); + + if (device) + unmap = dmaengine_get_unmap_data(device->dev, src_cnt, GFP_NOIO); + + if (unmap && src_cnt <= device->max_xor && + is_dma_xor_aligned(device, offset, 0, len)) { + unsigned long dma_prep_flags = 0; + int i; + + pr_debug("%s: (async) len: %zu\n", __func__, len); + + if (submit->cb_fn) + dma_prep_flags |= DMA_PREP_INTERRUPT; + if (submit->flags & ASYNC_TX_FENCE) + dma_prep_flags |= DMA_PREP_FENCE; + + for (i = 0; i < src_cnt; i++) { + unmap->addr[i] = dma_map_page(device->dev, src_list[i], + offset, len, DMA_TO_DEVICE); + unmap->to_cnt++; + } + unmap->len = len; + + tx = device->device_prep_dma_xor_val(chan, unmap->addr, src_cnt, + len, result, + dma_prep_flags); + if (unlikely(!tx)) { + async_tx_quiesce(&submit->depend_tx); + + while (!tx) { + dma_async_issue_pending(chan); + tx = device->device_prep_dma_xor_val(chan, + unmap->addr, src_cnt, len, result, + dma_prep_flags); + } + } + dma_set_unmap(tx, unmap); + async_tx_submit(chan, tx, submit); + } else { + enum async_tx_flags flags_orig = submit->flags; + + pr_debug("%s: (sync) len: %zu\n", __func__, len); + WARN_ONCE(device && src_cnt <= device->max_xor, + "%s: no space for dma address conversion\n", + __func__); + + submit->flags |= ASYNC_TX_XOR_DROP_DST; + submit->flags &= ~ASYNC_TX_ACK; + + tx = async_xor(dest, src_list, offset, src_cnt, len, submit); + + async_tx_quiesce(&tx); + + *result = !page_is_zero(dest, offset, len) << SUM_CHECK_P; + + async_tx_sync_epilog(submit); + submit->flags = flags_orig; + } + dmaengine_unmap_put(unmap); + + return tx; +} +EXPORT_SYMBOL_GPL(async_xor_val); + +MODULE_AUTHOR("Intel Corporation"); +MODULE_DESCRIPTION("asynchronous xor/xor-zero-sum api"); +MODULE_LICENSE("GPL"); diff --git a/kernel/crypto/async_tx/raid6test.c b/kernel/crypto/async_tx/raid6test.c new file mode 100644 index 000000000..dad95f45b --- /dev/null +++ b/kernel/crypto/async_tx/raid6test.c @@ -0,0 +1,253 @@ +/* + * asynchronous raid6 recovery self test + * Copyright (c) 2009, Intel Corporation. + * + * based on drivers/md/raid6test/test.c: + * Copyright 2002-2007 H. Peter Anvin + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions of the GNU General Public License, + * version 2, as published by the Free Software Foundation. + * + * This program is distributed in the hope it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + * + * You should have received a copy of the GNU General Public License along with + * this program; if not, write to the Free Software Foundation, Inc., + * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA. + * + */ +#include <linux/async_tx.h> +#include <linux/gfp.h> +#include <linux/mm.h> +#include <linux/random.h> +#include <linux/module.h> + +#undef pr +#define pr(fmt, args...) pr_info("raid6test: " fmt, ##args) + +#define NDISKS 64 /* Including P and Q */ + +static struct page *dataptrs[NDISKS]; +static addr_conv_t addr_conv[NDISKS]; +static struct page *data[NDISKS+3]; +static struct page *spare; +static struct page *recovi; +static struct page *recovj; + +static void callback(void *param) +{ + struct completion *cmp = param; + + complete(cmp); +} + +static void makedata(int disks) +{ + int i; + + for (i = 0; i < disks; i++) { + prandom_bytes(page_address(data[i]), PAGE_SIZE); + dataptrs[i] = data[i]; + } +} + +static char disk_type(int d, int disks) +{ + if (d == disks - 2) + return 'P'; + else if (d == disks - 1) + return 'Q'; + else + return 'D'; +} + +/* Recover two failed blocks. */ +static void raid6_dual_recov(int disks, size_t bytes, int faila, int failb, struct page **ptrs) +{ + struct async_submit_ctl submit; + struct completion cmp; + struct dma_async_tx_descriptor *tx = NULL; + enum sum_check_flags result = ~0; + + if (faila > failb) + swap(faila, failb); + + if (failb == disks-1) { + if (faila == disks-2) { + /* P+Q failure. Just rebuild the syndrome. */ + init_async_submit(&submit, 0, NULL, NULL, NULL, addr_conv); + tx = async_gen_syndrome(ptrs, 0, disks, bytes, &submit); + } else { + struct page *blocks[disks]; + struct page *dest; + int count = 0; + int i; + + /* data+Q failure. Reconstruct data from P, + * then rebuild syndrome + */ + for (i = disks; i-- ; ) { + if (i == faila || i == failb) + continue; + blocks[count++] = ptrs[i]; + } + dest = ptrs[faila]; + init_async_submit(&submit, ASYNC_TX_XOR_ZERO_DST, NULL, + NULL, NULL, addr_conv); + tx = async_xor(dest, blocks, 0, count, bytes, &submit); + + init_async_submit(&submit, 0, tx, NULL, NULL, addr_conv); + tx = async_gen_syndrome(ptrs, 0, disks, bytes, &submit); + } + } else { + if (failb == disks-2) { + /* data+P failure. */ + init_async_submit(&submit, 0, NULL, NULL, NULL, addr_conv); + tx = async_raid6_datap_recov(disks, bytes, faila, ptrs, &submit); + } else { + /* data+data failure. */ + init_async_submit(&submit, 0, NULL, NULL, NULL, addr_conv); + tx = async_raid6_2data_recov(disks, bytes, faila, failb, ptrs, &submit); + } + } + init_completion(&cmp); + init_async_submit(&submit, ASYNC_TX_ACK, tx, callback, &cmp, addr_conv); + tx = async_syndrome_val(ptrs, 0, disks, bytes, &result, spare, &submit); + async_tx_issue_pending(tx); + + if (wait_for_completion_timeout(&cmp, msecs_to_jiffies(3000)) == 0) + pr("%s: timeout! (faila: %d failb: %d disks: %d)\n", + __func__, faila, failb, disks); + + if (result != 0) + pr("%s: validation failure! faila: %d failb: %d sum_check_flags: %x\n", + __func__, faila, failb, result); +} + +static int test_disks(int i, int j, int disks) +{ + int erra, errb; + + memset(page_address(recovi), 0xf0, PAGE_SIZE); + memset(page_address(recovj), 0xba, PAGE_SIZE); + + dataptrs[i] = recovi; + dataptrs[j] = recovj; + + raid6_dual_recov(disks, PAGE_SIZE, i, j, dataptrs); + + erra = memcmp(page_address(data[i]), page_address(recovi), PAGE_SIZE); + errb = memcmp(page_address(data[j]), page_address(recovj), PAGE_SIZE); + + pr("%s(%d, %d): faila=%3d(%c) failb=%3d(%c) %s\n", + __func__, i, j, i, disk_type(i, disks), j, disk_type(j, disks), + (!erra && !errb) ? "OK" : !erra ? "ERRB" : !errb ? "ERRA" : "ERRAB"); + + dataptrs[i] = data[i]; + dataptrs[j] = data[j]; + + return erra || errb; +} + +static int test(int disks, int *tests) +{ + struct dma_async_tx_descriptor *tx; + struct async_submit_ctl submit; + struct completion cmp; + int err = 0; + int i, j; + + recovi = data[disks]; + recovj = data[disks+1]; + spare = data[disks+2]; + + makedata(disks); + + /* Nuke syndromes */ + memset(page_address(data[disks-2]), 0xee, PAGE_SIZE); + memset(page_address(data[disks-1]), 0xee, PAGE_SIZE); + + /* Generate assumed good syndrome */ + init_completion(&cmp); + init_async_submit(&submit, ASYNC_TX_ACK, NULL, callback, &cmp, addr_conv); + tx = async_gen_syndrome(dataptrs, 0, disks, PAGE_SIZE, &submit); + async_tx_issue_pending(tx); + + if (wait_for_completion_timeout(&cmp, msecs_to_jiffies(3000)) == 0) { + pr("error: initial gen_syndrome(%d) timed out\n", disks); + return 1; + } + + pr("testing the %d-disk case...\n", disks); + for (i = 0; i < disks-1; i++) + for (j = i+1; j < disks; j++) { + (*tests)++; + err += test_disks(i, j, disks); + } + + return err; +} + + +static int raid6_test(void) +{ + int err = 0; + int tests = 0; + int i; + + for (i = 0; i < NDISKS+3; i++) { + data[i] = alloc_page(GFP_KERNEL); + if (!data[i]) { + while (i--) + put_page(data[i]); + return -ENOMEM; + } + } + + /* the 4-disk and 5-disk cases are special for the recovery code */ + if (NDISKS > 4) + err += test(4, &tests); + if (NDISKS > 5) + err += test(5, &tests); + /* the 11 and 12 disk cases are special for ioatdma (p-disabled + * q-continuation without extended descriptor) + */ + if (NDISKS > 12) { + err += test(11, &tests); + err += test(12, &tests); + } + + /* the 24 disk case is special for ioatdma as it is the boudary point + * at which it needs to switch from 8-source ops to 16-source + * ops for continuation (assumes DMA_HAS_PQ_CONTINUE is not set) + */ + if (NDISKS > 24) + err += test(24, &tests); + + err += test(NDISKS, &tests); + + pr("\n"); + pr("complete (%d tests, %d failure%s)\n", + tests, err, err == 1 ? "" : "s"); + + for (i = 0; i < NDISKS+3; i++) + put_page(data[i]); + + return 0; +} + +static void raid6_test_exit(void) +{ +} + +/* when compiled-in wait for drivers to load first (assumes dma drivers + * are also compliled-in) + */ +late_initcall(raid6_test); +module_exit(raid6_test_exit); +MODULE_AUTHOR("Dan Williams <dan.j.williams@intel.com>"); +MODULE_DESCRIPTION("asynchronous RAID-6 recovery self tests"); +MODULE_LICENSE("GPL"); |