From 899077791403ff7a2d8cfaa87bd1a82d729463e2 Mon Sep 17 00:00:00 2001 From: Arnd Bergmann Date: Tue, 8 Dec 2015 16:32:27 +0100 Subject: [PATCH] netcp: try to reduce type confusion in descriptors The netcp driver produces tons of warnings when CONFIG_LPAE is enabled on ARM: drivers/net/ethernet/ti/netcp_core.c: In function 'netcp_tx_map_skb': drivers/net/ethernet/ti/netcp_core.c:1084:13: warning: passing argument 1 of 'set_words' from incompatible pointer type [-Wincompatible-pointer-types] This is the result of trying to pass a pointer to a dma_addr_t to a function that expects a u32 pointer to copy that into a DMA descriptor. Looking at that code in more detail to fix the warnings, I see multiple related problems: * The conversion functions are not endian-safe, as the DMA descriptors are almost certainly fixed-endian, but the CPU is not. * On 64-bit machines, passing a pointer through a u32 variable is a bug, accessing an indirect pointer as a u32 pointer even more so. * The handling of epib and psdata mixes native-endian and device-endian data. In this patch, I try to sort out the types for most accesses here, adding le32_to_cpu/cpu_to_le32 where appropriate, and passing pointers through two 32-bit words in the descriptor padding, to make it plausible that the driver does the right thing if compiled for big-endian or 64-bit systems. Signed-off-by: Arnd Bergmann Signed-off-by: David S. Miller --- drivers/net/ethernet/ti/netcp_core.c | 123 ++++++++++++++++----------- include/linux/soc/ti/knav_dma.h | 22 ++--- 2 files changed, 82 insertions(+), 63 deletions(-) diff --git a/drivers/net/ethernet/ti/netcp_core.c b/drivers/net/ethernet/ti/netcp_core.c index e5e20e734f21..eb2585e777e1 100644 --- a/drivers/net/ethernet/ti/netcp_core.c +++ b/drivers/net/ethernet/ti/netcp_core.c @@ -109,69 +109,80 @@ module_param(netcp_debug_level, int, 0); MODULE_PARM_DESC(netcp_debug_level, "Netcp debug level (NETIF_MSG bits) (0=none,...,16=all)"); /* Helper functions - Get/Set */ -static void get_pkt_info(u32 *buff, u32 *buff_len, u32 *ndesc, +static void get_pkt_info(dma_addr_t *buff, u32 *buff_len, dma_addr_t *ndesc, struct knav_dma_desc *desc) { - *buff_len = desc->buff_len; - *buff = desc->buff; - *ndesc = desc->next_desc; + *buff_len = le32_to_cpu(desc->buff_len); + *buff = le32_to_cpu(desc->buff); + *ndesc = le32_to_cpu(desc->next_desc); } -static void get_pad_info(u32 *pad0, u32 *pad1, struct knav_dma_desc *desc) +static void get_pad_info(u32 *pad0, u32 *pad1, u32 *pad2, struct knav_dma_desc *desc) { - *pad0 = desc->pad[0]; - *pad1 = desc->pad[1]; + *pad0 = le32_to_cpu(desc->pad[0]); + *pad1 = le32_to_cpu(desc->pad[1]); + *pad2 = le32_to_cpu(desc->pad[2]); } -static void get_org_pkt_info(u32 *buff, u32 *buff_len, +static void get_pad_ptr(void **padptr, struct knav_dma_desc *desc) +{ + u64 pad64; + + pad64 = le32_to_cpu(desc->pad[0]) + + ((u64)le32_to_cpu(desc->pad[1]) << 32); + *padptr = (void *)(uintptr_t)pad64; +} + +static void get_org_pkt_info(dma_addr_t *buff, u32 *buff_len, struct knav_dma_desc *desc) { - *buff = desc->orig_buff; - *buff_len = desc->orig_len; + *buff = le32_to_cpu(desc->orig_buff); + *buff_len = le32_to_cpu(desc->orig_len); } -static void get_words(u32 *words, int num_words, u32 *desc) +static void get_words(dma_addr_t *words, int num_words, __le32 *desc) { int i; for (i = 0; i < num_words; i++) - words[i] = desc[i]; + words[i] = le32_to_cpu(desc[i]); } -static void set_pkt_info(u32 buff, u32 buff_len, u32 ndesc, +static void set_pkt_info(dma_addr_t buff, u32 buff_len, u32 ndesc, struct knav_dma_desc *desc) { - desc->buff_len = buff_len; - desc->buff = buff; - desc->next_desc = ndesc; + desc->buff_len = cpu_to_le32(buff_len); + desc->buff = cpu_to_le32(buff); + desc->next_desc = cpu_to_le32(ndesc); } static void set_desc_info(u32 desc_info, u32 pkt_info, struct knav_dma_desc *desc) { - desc->desc_info = desc_info; - desc->packet_info = pkt_info; + desc->desc_info = cpu_to_le32(desc_info); + desc->packet_info = cpu_to_le32(pkt_info); } -static void set_pad_info(u32 pad0, u32 pad1, struct knav_dma_desc *desc) +static void set_pad_info(u32 pad0, u32 pad1, u32 pad2, struct knav_dma_desc *desc) { - desc->pad[0] = pad0; - desc->pad[1] = pad1; + desc->pad[0] = cpu_to_le32(pad0); + desc->pad[1] = cpu_to_le32(pad1); + desc->pad[2] = cpu_to_le32(pad1); } -static void set_org_pkt_info(u32 buff, u32 buff_len, +static void set_org_pkt_info(dma_addr_t buff, u32 buff_len, struct knav_dma_desc *desc) { - desc->orig_buff = buff; - desc->orig_len = buff_len; + desc->orig_buff = cpu_to_le32(buff); + desc->orig_len = cpu_to_le32(buff_len); } -static void set_words(u32 *words, int num_words, u32 *desc) +static void set_words(u32 *words, int num_words, __le32 *desc) { int i; for (i = 0; i < num_words; i++) - desc[i] = words[i]; + desc[i] = cpu_to_le32(words[i]); } /* Read the e-fuse value as 32 bit values to be endian independent */ @@ -570,7 +581,7 @@ static void netcp_free_rx_desc_chain(struct netcp_intf *netcp, dma_addr_t dma_desc, dma_buf; unsigned int buf_len, dma_sz = sizeof(*ndesc); void *buf_ptr; - u32 tmp; + u32 pad[2]; get_words(&dma_desc, 1, &desc->next_desc); @@ -580,14 +591,15 @@ static void netcp_free_rx_desc_chain(struct netcp_intf *netcp, dev_err(netcp->ndev_dev, "failed to unmap Rx desc\n"); break; } - get_pkt_info(&dma_buf, &tmp, &dma_desc, ndesc); - get_pad_info((u32 *)&buf_ptr, &tmp, ndesc); + get_pad_ptr(&buf_ptr, ndesc); dma_unmap_page(netcp->dev, dma_buf, PAGE_SIZE, DMA_FROM_DEVICE); __free_page(buf_ptr); knav_pool_desc_put(netcp->rx_pool, desc); } - get_pad_info((u32 *)&buf_ptr, &buf_len, desc); + get_pad_info(&pad[0], &pad[1], &buf_len, desc); + buf_ptr = (void *)(uintptr_t)(pad[0] + ((u64)pad[1] << 32)); + if (buf_ptr) netcp_frag_free(buf_len <= PAGE_SIZE, buf_ptr); knav_pool_desc_put(netcp->rx_pool, desc); @@ -626,7 +638,6 @@ static int netcp_process_one_rx_packet(struct netcp_intf *netcp) struct netcp_packet p_info; struct sk_buff *skb; void *org_buf_ptr; - u32 tmp; dma_desc = knav_queue_pop(netcp->rx_queue, &dma_sz); if (!dma_desc) @@ -639,7 +650,7 @@ static int netcp_process_one_rx_packet(struct netcp_intf *netcp) } get_pkt_info(&dma_buff, &buf_len, &dma_desc, desc); - get_pad_info((u32 *)&org_buf_ptr, &org_buf_len, desc); + get_pad_ptr(&org_buf_ptr, desc); if (unlikely(!org_buf_ptr)) { dev_err(netcp->ndev_dev, "NULL bufptr in desc\n"); @@ -664,6 +675,7 @@ static int netcp_process_one_rx_packet(struct netcp_intf *netcp) /* Fill in the page fragment list */ while (dma_desc) { struct page *page; + void *ptr; ndesc = knav_pool_desc_unmap(netcp->rx_pool, dma_desc, dma_sz); if (unlikely(!ndesc)) { @@ -672,14 +684,15 @@ static int netcp_process_one_rx_packet(struct netcp_intf *netcp) } get_pkt_info(&dma_buff, &buf_len, &dma_desc, ndesc); - get_pad_info((u32 *)&page, &tmp, ndesc); + get_pad_ptr(ptr, ndesc); + page = ptr; if (likely(dma_buff && buf_len && page)) { dma_unmap_page(netcp->dev, dma_buff, PAGE_SIZE, DMA_FROM_DEVICE); } else { - dev_err(netcp->ndev_dev, "Bad Rx desc dma_buff(%p), len(%d), page(%p)\n", - (void *)dma_buff, buf_len, page); + dev_err(netcp->ndev_dev, "Bad Rx desc dma_buff(%pad), len(%d), page(%p)\n", + &dma_buff, buf_len, page); goto free_desc; } @@ -750,7 +763,6 @@ static void netcp_free_rx_buf(struct netcp_intf *netcp, int fdq) unsigned int buf_len, dma_sz; dma_addr_t dma; void *buf_ptr; - u32 tmp; /* Allocate descriptor */ while ((dma = knav_queue_pop(netcp->rx_fdq[fdq], &dma_sz))) { @@ -761,7 +773,7 @@ static void netcp_free_rx_buf(struct netcp_intf *netcp, int fdq) } get_org_pkt_info(&dma, &buf_len, desc); - get_pad_info((u32 *)&buf_ptr, &tmp, desc); + get_pad_ptr(buf_ptr, desc); if (unlikely(!dma)) { dev_err(netcp->ndev_dev, "NULL orig_buff in desc\n"); @@ -813,7 +825,7 @@ static int netcp_allocate_rx_buf(struct netcp_intf *netcp, int fdq) struct page *page; dma_addr_t dma; void *bufptr; - u32 pad[2]; + u32 pad[3]; /* Allocate descriptor */ hwdesc = knav_pool_desc_get(netcp->rx_pool); @@ -830,7 +842,7 @@ static int netcp_allocate_rx_buf(struct netcp_intf *netcp, int fdq) SKB_DATA_ALIGN(sizeof(struct skb_shared_info)); bufptr = netdev_alloc_frag(primary_buf_len); - pad[1] = primary_buf_len; + pad[2] = primary_buf_len; if (unlikely(!bufptr)) { dev_warn_ratelimited(netcp->ndev_dev, @@ -842,7 +854,8 @@ static int netcp_allocate_rx_buf(struct netcp_intf *netcp, int fdq) if (unlikely(dma_mapping_error(netcp->dev, dma))) goto fail; - pad[0] = (u32)bufptr; + pad[0] = lower_32_bits((uintptr_t)bufptr); + pad[1] = upper_32_bits((uintptr_t)bufptr); } else { /* Allocate a secondary receive queue entry */ @@ -853,8 +866,9 @@ static int netcp_allocate_rx_buf(struct netcp_intf *netcp, int fdq) } buf_len = PAGE_SIZE; dma = dma_map_page(netcp->dev, page, 0, buf_len, DMA_TO_DEVICE); - pad[0] = (u32)page; - pad[1] = 0; + pad[0] = lower_32_bits(dma); + pad[1] = upper_32_bits(dma); + pad[2] = 0; } desc_info = KNAV_DMA_DESC_PS_INFO_IN_DESC; @@ -864,7 +878,7 @@ static int netcp_allocate_rx_buf(struct netcp_intf *netcp, int fdq) pkt_info |= (netcp->rx_queue_id & KNAV_DMA_DESC_RETQ_MASK) << KNAV_DMA_DESC_RETQ_SHIFT; set_org_pkt_info(dma, buf_len, hwdesc); - set_pad_info(pad[0], pad[1], hwdesc); + set_pad_info(pad[0], pad[1], pad[2], hwdesc); set_desc_info(desc_info, pkt_info, hwdesc); /* Push to FDQs */ @@ -935,8 +949,8 @@ static void netcp_free_tx_desc_chain(struct netcp_intf *netcp, dma_unmap_single(netcp->dev, dma_buf, buf_len, DMA_TO_DEVICE); else - dev_warn(netcp->ndev_dev, "bad Tx desc buf(%p), len(%d)\n", - (void *)dma_buf, buf_len); + dev_warn(netcp->ndev_dev, "bad Tx desc buf(%pad), len(%d)\n", + &dma_buf, buf_len); knav_pool_desc_put(netcp->tx_pool, ndesc); ndesc = NULL; @@ -953,11 +967,11 @@ static int netcp_process_tx_compl_packets(struct netcp_intf *netcp, unsigned int budget) { struct knav_dma_desc *desc; + void *ptr; struct sk_buff *skb; unsigned int dma_sz; dma_addr_t dma; int pkts = 0; - u32 tmp; while (budget--) { dma = knav_queue_pop(netcp->tx_compl_q, &dma_sz); @@ -970,7 +984,8 @@ static int netcp_process_tx_compl_packets(struct netcp_intf *netcp, continue; } - get_pad_info((u32 *)&skb, &tmp, desc); + get_pad_ptr(&ptr, desc); + skb = ptr; netcp_free_tx_desc_chain(netcp, desc, dma_sz); if (!skb) { dev_err(netcp->ndev_dev, "No skb in Tx desc\n"); @@ -1059,6 +1074,7 @@ netcp_tx_map_skb(struct sk_buff *skb, struct netcp_intf *netcp) u32 page_offset = frag->page_offset; u32 buf_len = skb_frag_size(frag); dma_addr_t desc_dma; + u32 desc_dma_32; u32 pkt_info; dma_addr = dma_map_page(dev, page, page_offset, buf_len, @@ -1075,13 +1091,13 @@ netcp_tx_map_skb(struct sk_buff *skb, struct netcp_intf *netcp) goto free_descs; } - desc_dma = knav_pool_desc_virt_to_dma(netcp->tx_pool, - (void *)ndesc); + desc_dma = knav_pool_desc_virt_to_dma(netcp->tx_pool, ndesc); pkt_info = (netcp->tx_compl_qid & KNAV_DMA_DESC_RETQ_MASK) << KNAV_DMA_DESC_RETQ_SHIFT; set_pkt_info(dma_addr, buf_len, 0, ndesc); - set_words(&desc_dma, 1, &pdesc->next_desc); + desc_dma_32 = (u32)desc_dma; + set_words(&desc_dma_32, 1, &pdesc->next_desc); pkt_len += buf_len; if (pdesc != desc) knav_pool_desc_map(netcp->tx_pool, pdesc, @@ -1173,11 +1189,14 @@ static int netcp_tx_submit_skb(struct netcp_intf *netcp, } set_words(&tmp, 1, &desc->packet_info); - set_words((u32 *)&skb, 1, &desc->pad[0]); + tmp = lower_32_bits((uintptr_t)&skb); + set_words(&tmp, 1, &desc->pad[0]); + tmp = upper_32_bits((uintptr_t)&skb); + set_words(&tmp, 1, &desc->pad[1]); if (tx_pipe->flags & SWITCH_TO_PORT_IN_TAGINFO) { tmp = tx_pipe->switch_to_port; - set_words((u32 *)&tmp, 1, &desc->tag_info); + set_words(&tmp, 1, &desc->tag_info); } /* submit packet descriptor */ diff --git a/include/linux/soc/ti/knav_dma.h b/include/linux/soc/ti/knav_dma.h index dad035c16d94..343c13ac4f71 100644 --- a/include/linux/soc/ti/knav_dma.h +++ b/include/linux/soc/ti/knav_dma.h @@ -144,17 +144,17 @@ struct knav_dma_cfg { * @psdata: Protocol specific */ struct knav_dma_desc { - u32 desc_info; - u32 tag_info; - u32 packet_info; - u32 buff_len; - u32 buff; - u32 next_desc; - u32 orig_len; - u32 orig_buff; - u32 epib[KNAV_DMA_NUM_EPIB_WORDS]; - u32 psdata[KNAV_DMA_NUM_PS_WORDS]; - u32 pad[4]; + __le32 desc_info; + __le32 tag_info; + __le32 packet_info; + __le32 buff_len; + __le32 buff; + __le32 next_desc; + __le32 orig_len; + __le32 orig_buff; + __le32 epib[KNAV_DMA_NUM_EPIB_WORDS]; + __le32 psdata[KNAV_DMA_NUM_PS_WORDS]; + __le32 pad[4]; } ____cacheline_aligned; #if IS_ENABLED(CONFIG_KEYSTONE_NAVIGATOR_DMA)