diff options
Diffstat (limited to 'crypto/async_tx/async_xor.c')
| -rw-r--r-- | crypto/async_tx/async_xor.c | 453 |
1 files changed, 223 insertions, 230 deletions
diff --git a/crypto/async_tx/async_xor.c b/crypto/async_tx/async_xor.c index 1c445c7bdab..3c562f5a60b 100644 --- a/crypto/async_tx/async_xor.c +++ b/crypto/async_tx/async_xor.c @@ -25,328 +25,321 @@ */ #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. - * This routine is marked __always_inline so it can be compiled away - * when CONFIG_DMA_ENGINE=n - */ -static __always_inline struct dma_async_tx_descriptor * -do_async_xor(struct dma_device *device, - struct dma_chan *chan, struct page *dest, struct page **src_list, - unsigned int offset, unsigned int src_cnt, size_t len, - enum async_tx_flags flags, struct dma_async_tx_descriptor *depend_tx, - dma_async_tx_callback cb_fn, void *cb_param) +/* 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) { - dma_addr_t dma_dest; - dma_addr_t *dma_src = (dma_addr_t *) src_list; - struct dma_async_tx_descriptor *tx; - int i; - unsigned long dma_prep_flags = cb_fn ? DMA_PREP_INTERRUPT : 0; + 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; - pr_debug("%s: len: %zu\n", __func__, len); + while (src_cnt) { + dma_addr_t tmp; - dma_dest = dma_map_page(device->dev, dest, offset, len, - DMA_FROM_DEVICE); + 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; - for (i = 0; i < src_cnt; i++) - dma_src[i] = dma_map_page(device->dev, src_list[i], offset, - len, DMA_TO_DEVICE); - - /* Since we have clobbered the src_list we are committed - * to doing this asynchronously. Drivers force forward progress - * in case they can not provide a descriptor - */ - tx = device->device_prep_dma_xor(chan, dma_dest, dma_src, src_cnt, len, - dma_prep_flags); - if (!tx) { - if (depend_tx) - dma_wait_for_async_tx(depend_tx); - - while (!tx) - tx = device->device_prep_dma_xor(chan, dma_dest, - dma_src, src_cnt, len, - dma_prep_flags); - } + /* 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); + src_list[0] = tmp; + + + 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); + } - async_tx_submit(chan, tx, flags, depend_tx, cb_fn, cb_param); + 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, - unsigned int src_cnt, size_t len, enum async_tx_flags flags, - struct dma_async_tx_descriptor *depend_tx, - dma_async_tx_callback cb_fn, void *cb_param) + int src_cnt, size_t len, struct async_submit_ctl *submit) { - void *_dest; int i; + int xor_src_cnt = 0; + int src_off = 0; + void *dest_buf; + void **srcs; - pr_debug("%s: len: %zu\n", __func__, len); + if (submit->scribble) + srcs = submit->scribble; + else + srcs = (void **) src_list; - /* reuse the 'src_list' array to convert to buffer pointers */ + /* convert to buffer pointers */ for (i = 0; i < src_cnt; i++) - src_list[i] = (struct page *) - (page_address(src_list[i]) + offset); - + if (src_list[i]) + srcs[xor_src_cnt++] = page_address(src_list[i]) + offset; + src_cnt = xor_src_cnt; /* set destination address */ - _dest = page_address(dest) + offset; + dest_buf = page_address(dest) + offset; - if (flags & ASYNC_TX_XOR_ZERO_DST) - memset(_dest, 0, len); + if (submit->flags & ASYNC_TX_XOR_ZERO_DST) + memset(dest_buf, 0, len); - xor_blocks(src_cnt, len, _dest, - (void **) src_list); + 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]); - async_tx_sync_epilog(flags, depend_tx, cb_fn, cb_param); + /* 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. - * 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. * @dest: destination page - * @src_list: array of source pages (if the dest is also a source it must be - * at index zero). The contents of this array may be overwritten. - * @offset: offset in pages to start transaction + * @src_list: array of source pages + * @offset: common src/dst offset to start transaction * @src_cnt: number of source pages * @len: length in bytes - * @flags: ASYNC_TX_XOR_ZERO_DST, ASYNC_TX_XOR_DROP_DEST, - * ASYNC_TX_ACK, ASYNC_TX_DEP_ACK - * @depend_tx: xor depends on the result of this transaction. - * @cb_fn: function to call when the xor completes - * @cb_param: parameter to pass to the callback routine + * @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, enum async_tx_flags flags, - struct dma_async_tx_descriptor *depend_tx, - dma_async_tx_callback cb_fn, void *cb_param) + int src_cnt, size_t len, struct async_submit_ctl *submit) { - struct dma_chan *chan = async_tx_find_channel(depend_tx, DMA_XOR, + 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 dma_async_tx_descriptor *tx = NULL; - dma_async_tx_callback _cb_fn; - void *_cb_param; - unsigned long local_flags; - int xor_src_cnt; - int i = 0, src_off = 0; + struct dmaengine_unmap_data *unmap = NULL; BUG_ON(src_cnt <= 1); - while (src_cnt) { - local_flags = flags; - if (device) { /* run the xor asynchronously */ - xor_src_cnt = min(src_cnt, device->max_xor); - /* if we are submitting additional xors - * only set the callback on the last transaction - */ - if (src_cnt > xor_src_cnt) { - local_flags &= ~ASYNC_TX_ACK; - _cb_fn = NULL; - _cb_param = NULL; - } else { - _cb_fn = cb_fn; - _cb_param = cb_param; - } - - tx = do_async_xor(device, chan, dest, - &src_list[src_off], offset, - xor_src_cnt, len, local_flags, - depend_tx, _cb_fn, _cb_param); - } else { /* run the xor synchronously */ - /* in the sync case the dest is an implied source - * (assumes the dest is at the src_off index) - */ - if (flags & ASYNC_TX_XOR_DROP_DST) { - src_cnt--; - src_off++; - } + if (device) + unmap = dmaengine_get_unmap_data(device->dev, src_cnt+1, GFP_NOIO); - /* process up to 'MAX_XOR_BLOCKS' sources */ - xor_src_cnt = min(src_cnt, MAX_XOR_BLOCKS); - - /* if we are submitting additional xors - * only set the callback on the last transaction - */ - if (src_cnt > xor_src_cnt) { - local_flags &= ~ASYNC_TX_ACK; - _cb_fn = NULL; - _cb_param = NULL; - } else { - _cb_fn = cb_fn; - _cb_param = cb_param; - } + if (unmap && is_dma_xor_aligned(device, offset, 0, len)) { + struct dma_async_tx_descriptor *tx; + int i, j; - /* wait for any prerequisite operations */ - if (depend_tx) { - /* if ack is already set then we cannot be sure - * we are referring to the correct operation - */ - BUG_ON(depend_tx->ack); - if (dma_wait_for_async_tx(depend_tx) == - DMA_ERROR) - panic("%s: DMA_ERROR waiting for " - "depend_tx\n", - __func__); - } + /* run the xor asynchronously */ + pr_debug("%s (async): len: %zu\n", __func__, len); - do_sync_xor(dest, &src_list[src_off], offset, - xor_src_cnt, len, local_flags, depend_tx, - _cb_fn, _cb_param); + 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); } - /* the previous tx is hidden from the client, - * so ack it - */ - if (i && depend_tx) - async_tx_ack(depend_tx); + /* 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; - depend_tx = tx; + 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++; + } - if (src_cnt > xor_src_cnt) { - /* drop completed sources */ - src_cnt -= xor_src_cnt; - src_off += xor_src_cnt; + /* wait for any prerequisite operations */ + async_tx_quiesce(&submit->depend_tx); - /* unconditionally preserve the destination */ - flags &= ~ASYNC_TX_XOR_ZERO_DST; + do_sync_xor(dest, src_list, offset, src_cnt, len, submit); - /* use the intermediate result a source, but remember - * it's dropped, because it's implied, in the sync case - */ - src_list[--src_off] = dest; - src_cnt++; - flags |= ASYNC_TX_XOR_DROP_DST; - } else - src_cnt = 0; - i++; + return NULL; } - - return tx; } EXPORT_SYMBOL_GPL(async_xor); static int page_is_zero(struct page *p, unsigned int offset, size_t len) { - char *a = page_address(p) + offset; - return ((*(u32 *) a) == 0 && - memcmp(a, a + 4, len - 4) == 0); + 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_zero_sum - attempt a xor parity check with a dma engine. + * 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. The dest page must be listed as a source - * at index zero. The contents of this array may be overwritten. + * @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 - * @flags: ASYNC_TX_ACK, ASYNC_TX_DEP_ACK - * @depend_tx: xor depends on the result of this transaction. - * @cb_fn: function to call when the xor completes - * @cb_param: parameter to pass to the callback routine + * @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_zero_sum(struct page *dest, struct page **src_list, - unsigned int offset, int src_cnt, size_t len, - u32 *result, enum async_tx_flags flags, - struct dma_async_tx_descriptor *depend_tx, - dma_async_tx_callback cb_fn, void *cb_param) +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 = async_tx_find_channel(depend_tx, DMA_ZERO_SUM, - &dest, 1, src_list, - src_cnt, len); + 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 && src_cnt <= device->max_xor) { - dma_addr_t *dma_src = (dma_addr_t *) src_list; - unsigned long dma_prep_flags = cb_fn ? DMA_PREP_INTERRUPT : 0; + 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); - for (i = 0; i < src_cnt; i++) - dma_src[i] = dma_map_page(device->dev, src_list[i], - offset, len, DMA_TO_DEVICE); - - tx = device->device_prep_dma_zero_sum(chan, dma_src, src_cnt, - len, result, - dma_prep_flags); - if (!tx) { - if (depend_tx) - dma_wait_for_async_tx(depend_tx); + if (submit->cb_fn) + dma_prep_flags |= DMA_PREP_INTERRUPT; + if (submit->flags & ASYNC_TX_FENCE) + dma_prep_flags |= DMA_PREP_FENCE; - while (!tx) - tx = device->device_prep_dma_zero_sum(chan, - dma_src, src_cnt, len, result, + 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); + } } - - async_tx_submit(chan, tx, flags, depend_tx, cb_fn, cb_param); + dma_set_unmap(tx, unmap); + async_tx_submit(chan, tx, submit); } else { - unsigned long xor_flags = flags; + 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__); - xor_flags |= ASYNC_TX_XOR_DROP_DST; - xor_flags &= ~ASYNC_TX_ACK; - - tx = async_xor(dest, src_list, offset, src_cnt, len, xor_flags, - depend_tx, NULL, NULL); + submit->flags |= ASYNC_TX_XOR_DROP_DST; + submit->flags &= ~ASYNC_TX_ACK; - if (tx) { - if (dma_wait_for_async_tx(tx) == DMA_ERROR) - panic("%s: DMA_ERROR waiting for tx\n", - __func__); - async_tx_ack(tx); - } + tx = async_xor(dest, src_list, offset, src_cnt, len, submit); - *result = page_is_zero(dest, offset, len) ? 0 : 1; + async_tx_quiesce(&tx); - tx = NULL; + *result = !page_is_zero(dest, offset, len) << SUM_CHECK_P; - async_tx_sync_epilog(flags, depend_tx, cb_fn, cb_param); + async_tx_sync_epilog(submit); + submit->flags = flags_orig; } + dmaengine_unmap_put(unmap); return tx; } -EXPORT_SYMBOL_GPL(async_xor_zero_sum); - -static int __init async_xor_init(void) -{ - #ifdef CONFIG_DMA_ENGINE - /* To conserve stack space the input src_list (array of page pointers) - * is reused to hold the array of dma addresses passed to the driver. - * This conversion is only possible when dma_addr_t is less than the - * the size of a pointer. HIGHMEM64G is known to violate this - * assumption. - */ - BUILD_BUG_ON(sizeof(dma_addr_t) > sizeof(struct page *)); - #endif - - return 0; -} - -static void __exit async_xor_exit(void) -{ - do { } while (0); -} - -module_init(async_xor_init); -module_exit(async_xor_exit); +EXPORT_SYMBOL_GPL(async_xor_val); MODULE_AUTHOR("Intel Corporation"); MODULE_DESCRIPTION("asynchronous xor/xor-zero-sum api"); |
