ALSA: qc_audio_offload: rename dma/iova/va/cpu/phys variables

While trying to understand a bug in the audio offload code, I had
to spend extra time due to unfortunate nameing of local variables
and struct members.

Change these to more conventional names that reflect the actual
usage:

 - pointers to the CPU virtual addresses of a dma buffer get a
   _cpu suffix to disambiguate them for MMIO virtual addresses

 - MMIO virtual addresses that are mapped explicitly through
   the IOMMU get a _iova suffix consistently, rather than a
   mix of iova and va.

 - DMA addresses (dma_addr_t) that are in a device address
   space (linear or IOMMU) get a _dma suffix in place of the
   _pa suffix.

 - CPU physical (phys_addr_t) addresses get a _pa suffix.
   There is still a mixup with dma addresses here that I address
   in another patch.

No functional changes are intended here.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/20250513123442.159936-2-arnd@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/sound/usb/qcom/qc_audio_offload.c b/sound/usb/qcom/qc_audio_offload.c
index 65ba4d90d438be8abb551bcc30d4af204decbb07..613e64f706ba19745ce5271d60e20c15de7a3eda 100644 (file)
--- a/sound/usb/qcom/qc_audio_offload.c
+++ b/sound/usb/qcom/qc_audio_offload.c
@@ -78,10 +78,10 @@ struct intf_info {
        size_t data_xfer_ring_size;
        unsigned long sync_xfer_ring_va;
        size_t sync_xfer_ring_size;
-       unsigned long xfer_buf_va;
+       unsigned long xfer_buf_iova;
        size_t xfer_buf_size;
-       phys_addr_t xfer_buf_pa;
-       u8 *xfer_buf;
+       phys_addr_t xfer_buf_dma;
+       u8 *xfer_buf_cpu;
 
        /* USB endpoint information */
        unsigned int data_ep_pipe;
@@ -396,7 +396,7 @@ static unsigned long uaudio_get_iova(unsigned long *curr_iova,
        struct iova_info *info, *new_info = NULL;
        struct list_head *curr_head;
        size_t tmp_size = size;
-       unsigned long va = 0;
+       unsigned long iova = 0;
 
        if (size % PAGE_SIZE)
                goto done;
@@ -411,7 +411,7 @@ static unsigned long uaudio_get_iova(unsigned long *curr_iova,
                /* exact size iova_info */
                if (!info->in_use && info->size == size) {
                        info->in_use = true;
-                       va = info->start_iova;
+                       iova = info->start_iova;
                        *curr_iova_size -= size;
                        goto done;
                } else if (!info->in_use && tmp_size >= info->size) {
@@ -421,7 +421,7 @@ static unsigned long uaudio_get_iova(unsigned long *curr_iova,
                        if (tmp_size)
                                continue;
 
-                       va = new_info->start_iova;
+                       iova = new_info->start_iova;
                        for (curr_head = &new_info->list; curr_head !=
                        &info->list; curr_head = curr_head->next) {
                                new_info = list_entry(curr_head, struct
@@ -440,11 +440,11 @@ static unsigned long uaudio_get_iova(unsigned long *curr_iova,
 
        info = kzalloc(sizeof(*info), GFP_KERNEL);
        if (!info) {
-               va = 0;
+               iova = 0;
                goto done;
        }
 
-       va = *curr_iova;
+       iova = *curr_iova;
        info->start_iova = *curr_iova;
        info->size = size;
        info->in_use = true;
@@ -453,10 +453,10 @@ static unsigned long uaudio_get_iova(unsigned long *curr_iova,
        list_add_tail(&info->list, head);
 
 done:
-       return va;
+       return iova;
 }
 
-static void uaudio_put_iova(unsigned long va, size_t size, struct list_head
+static void uaudio_put_iova(unsigned long iova, size_t size, struct list_head
        *head, size_t *curr_iova_size)
 {
        struct iova_info *info;
@@ -464,7 +464,7 @@ static void uaudio_put_iova(unsigned long va, size_t size, struct list_head
        bool found = false;
 
        list_for_each_entry(info, head, list) {
-               if (info->start_iova == va) {
+               if (info->start_iova == iova) {
                        if (!info->in_use)
                                return;
 
@@ -492,20 +492,20 @@ done:
 /**
  * uaudio_iommu_unmap() - unmaps iommu memory for adsp
  * @mtype: ring type
- * @va: virtual address to unmap
+ * @iova: virtual address to unmap
  * @iova_size: region size
  * @mapped_iova_size: mapped region size
  *
  * Unmaps the memory region that was previously assigned to the adsp.
  *
  */
-static void uaudio_iommu_unmap(enum mem_type mtype, unsigned long va,
+static void uaudio_iommu_unmap(enum mem_type mtype, unsigned long iova,
                               size_t iova_size, size_t mapped_iova_size)
 {
        size_t umap_size;
        bool unmap = true;
 
-       if (!va || !iova_size)
+       if (!iova || !iova_size)
                return;
 
        switch (mtype) {
@@ -517,11 +517,11 @@ static void uaudio_iommu_unmap(enum mem_type mtype, unsigned long va,
                break;
 
        case MEM_XFER_RING:
-               uaudio_put_iova(va, iova_size, &uaudio_qdev->xfer_ring_list,
+               uaudio_put_iova(iova, iova_size, &uaudio_qdev->xfer_ring_list,
                                &uaudio_qdev->xfer_ring_iova_size);
                break;
        case MEM_XFER_BUF:
-               uaudio_put_iova(va, iova_size, &uaudio_qdev->xfer_buf_list,
+               uaudio_put_iova(iova, iova_size, &uaudio_qdev->xfer_buf_list,
                                &uaudio_qdev->xfer_buf_iova_size);
                break;
        default:
@@ -531,11 +531,11 @@ static void uaudio_iommu_unmap(enum mem_type mtype, unsigned long va,
        if (!unmap || !mapped_iova_size)
                return;
 
-       umap_size = iommu_unmap(uaudio_qdev->data->domain, va, mapped_iova_size);
+       umap_size = iommu_unmap(uaudio_qdev->data->domain, iova, mapped_iova_size);
        if (umap_size != mapped_iova_size)
                dev_err(uaudio_qdev->data->dev,
                        "unmapped size %zu for iova 0x%08lx of mapped size %zu\n",
-                       umap_size, va, mapped_iova_size);
+                       umap_size, iova, mapped_iova_size);
 }
 
 /**
@@ -556,9 +556,9 @@ static unsigned long uaudio_iommu_map(enum mem_type mtype, bool dma_coherent,
                                      struct sg_table *sgt)
 {
        struct scatterlist *sg;
-       unsigned long va = 0;
+       unsigned long iova = 0;
        size_t total_len = 0;
-       unsigned long va_sg;
+       unsigned long iova_sg;
        phys_addr_t pa_sg;
        bool map = true;
        size_t sg_len;
@@ -573,18 +573,18 @@ static unsigned long uaudio_iommu_map(enum mem_type mtype, bool dma_coherent,
 
        switch (mtype) {
        case MEM_EVENT_RING:
-               va = IOVA_BASE;
+               iova = IOVA_BASE;
                /* er already mapped */
                if (uaudio_qdev->er_mapped)
                        map = false;
                break;
        case MEM_XFER_RING:
-               va = uaudio_get_iova(&uaudio_qdev->curr_xfer_ring_iova,
+               iova = uaudio_get_iova(&uaudio_qdev->curr_xfer_ring_iova,
                                     &uaudio_qdev->xfer_ring_iova_size,
                                     &uaudio_qdev->xfer_ring_list, size);
                break;
        case MEM_XFER_BUF:
-               va = uaudio_get_iova(&uaudio_qdev->curr_xfer_buf_iova,
+               iova = uaudio_get_iova(&uaudio_qdev->curr_xfer_buf_iova,
                                     &uaudio_qdev->xfer_buf_iova_size,
                                     &uaudio_qdev->xfer_buf_list, size);
                break;
@@ -592,39 +592,39 @@ static unsigned long uaudio_iommu_map(enum mem_type mtype, bool dma_coherent,
                dev_err(uaudio_qdev->data->dev, "unknown mem type %d\n", mtype);
        }
 
-       if (!va || !map)
+       if (!iova || !map)
                goto done;
 
        if (!sgt)
                goto skip_sgt_map;
 
-       va_sg = va;
+       iova_sg = iova;
        for_each_sg(sgt->sgl, sg, sgt->nents, i) {
                sg_len = PAGE_ALIGN(sg->offset + sg->length);
                pa_sg = page_to_phys(sg_page(sg));
-               ret = iommu_map(uaudio_qdev->data->domain, va_sg, pa_sg, sg_len,
+               ret = iommu_map(uaudio_qdev->data->domain, iova_sg, pa_sg, sg_len,
                                prot, GFP_KERNEL);
                if (ret) {
-                       uaudio_iommu_unmap(MEM_XFER_BUF, va, size, total_len);
-                       va = 0;
+                       uaudio_iommu_unmap(MEM_XFER_BUF, iova, size, total_len);
+                       iova = 0;
                        goto done;
                }
 
-               va_sg += sg_len;
+               iova_sg += sg_len;
                total_len += sg_len;
        }
 
        if (size != total_len) {
-               uaudio_iommu_unmap(MEM_XFER_BUF, va, size, total_len);
-               va = 0;
+               uaudio_iommu_unmap(MEM_XFER_BUF, iova, size, total_len);
+               iova = 0;
        }
-       return va;
+       return iova;
 
 skip_sgt_map:
-       iommu_map(uaudio_qdev->data->domain, va, pa, size, prot, GFP_KERNEL);
+       iommu_map(uaudio_qdev->data->domain, iova, pa, size, prot, GFP_KERNEL);
 
 done:
-       return va;
+       return iova;
 }
 
 /* looks up alias, if any, for controller DT node and returns the index */
@@ -658,15 +658,15 @@ static void uaudio_dev_intf_cleanup(struct usb_device *udev, struct intf_info *i
        info->sync_xfer_ring_va = 0;
        info->sync_xfer_ring_size = 0;
 
-       uaudio_iommu_unmap(MEM_XFER_BUF, info->xfer_buf_va, info->xfer_buf_size,
+       uaudio_iommu_unmap(MEM_XFER_BUF, info->xfer_buf_iova, info->xfer_buf_size,
                           info->xfer_buf_size);
-       info->xfer_buf_va = 0;
+       info->xfer_buf_iova = 0;
 
-       usb_free_coherent(udev, info->xfer_buf_size, info->xfer_buf,
-                         info->xfer_buf_pa);
+       usb_free_coherent(udev, info->xfer_buf_size, info->xfer_buf_cpu,
+                         info->xfer_buf_dma);
        info->xfer_buf_size = 0;
-       info->xfer_buf = NULL;
-       info->xfer_buf_pa = 0;
+       info->xfer_buf_cpu = NULL;
+       info->xfer_buf_dma = 0;
 
        info->in_use = false;
 }
@@ -1021,7 +1021,7 @@ static int uaudio_transfer_buffer_setup(struct snd_usb_substream *subs,
        phys_addr_t xfer_buf_pa;
        u32 len = xfer_buf_len;
        bool dma_coherent;
-       unsigned long va;
+       unsigned long iova;
        u32 remainder;
        u32 mult;
        int ret;
@@ -1050,16 +1050,16 @@ static int uaudio_transfer_buffer_setup(struct snd_usb_substream *subs,
 
        dma_get_sgtable(subs->dev->bus->sysdev, &xfer_buf_sgt, xfer_buf,
                        xfer_buf_pa, len);
-       va = uaudio_iommu_map(MEM_XFER_BUF, dma_coherent, xfer_buf_pa, len,
+       iova = uaudio_iommu_map(MEM_XFER_BUF, dma_coherent, xfer_buf_pa, len,
                              &xfer_buf_sgt);
-       if (!va) {
+       if (!iova) {
                ret = -ENOMEM;
                goto unmap_sync;
        }
 
-       mem_info->pa = xfer_buf_pa;
+       mem_info->dma = xfer_buf_pa;
        mem_info->size = len;
-       mem_info->va = PREPEND_SID_TO_IOVA(va, uaudio_qdev->data->sid);
+       mem_info->iova = PREPEND_SID_TO_IOVA(iova, uaudio_qdev->data->sid);
        sg_free_table(&xfer_buf_sgt);
 
        return 0;
@@ -1094,7 +1094,7 @@ uaudio_endpoint_setup(struct snd_usb_substream *subs,
        phys_addr_t tr_pa = 0;
        struct sg_table *sgt;
        bool dma_coherent;
-       unsigned long va;
+       unsigned long iova;
        struct page *pg;
        int ret = -ENODEV;
 
@@ -1127,24 +1127,24 @@ uaudio_endpoint_setup(struct snd_usb_substream *subs,
 
        pg = sg_page(sgt->sgl);
        tr_pa = page_to_phys(pg);
-       mem_info->pa = sg_dma_address(sgt->sgl);
+       mem_info->dma = sg_dma_address(sgt->sgl);
        sg_free_table(sgt);
 
        /* data transfer ring */
-       va = uaudio_iommu_map(MEM_XFER_RING, dma_coherent, tr_pa,
+       iova = uaudio_iommu_map(MEM_XFER_RING, dma_coherent, tr_pa,
                              PAGE_SIZE, NULL);
-       if (!va) {
+       if (!iova) {
                ret = -ENOMEM;
                goto clear_pa;
        }
 
-       mem_info->va = PREPEND_SID_TO_IOVA(va, uaudio_qdev->data->sid);
+       mem_info->iova = PREPEND_SID_TO_IOVA(iova, uaudio_qdev->data->sid);
        mem_info->size = PAGE_SIZE;
 
        return 0;
 
 clear_pa:
-       mem_info->pa = 0;
+       mem_info->dma = 0;
 remove_ep:
        xhci_sideband_remove_endpoint(uadev[card_num].sb, ep);
 exit:
@@ -1167,7 +1167,7 @@ static int uaudio_event_ring_setup(struct snd_usb_substream *subs,
        struct sg_table *sgt;
        phys_addr_t er_pa;
        bool dma_coherent;
-       unsigned long va;
+       unsigned long iova;
        struct page *pg;
        int ret;
 
@@ -1192,23 +1192,23 @@ static int uaudio_event_ring_setup(struct snd_usb_substream *subs,
 
        pg = sg_page(sgt->sgl);
        er_pa = page_to_phys(pg);
-       mem_info->pa = sg_dma_address(sgt->sgl);
+       mem_info->dma = sg_dma_address(sgt->sgl);
        sg_free_table(sgt);
 
-       va = uaudio_iommu_map(MEM_EVENT_RING, dma_coherent, er_pa,
+       iova = uaudio_iommu_map(MEM_EVENT_RING, dma_coherent, er_pa,
                              PAGE_SIZE, NULL);
-       if (!va) {
+       if (!iova) {
                ret = -ENOMEM;
                goto clear_pa;
        }
 
-       mem_info->va = PREPEND_SID_TO_IOVA(va, uaudio_qdev->data->sid);
+       mem_info->iova = PREPEND_SID_TO_IOVA(iova, uaudio_qdev->data->sid);
        mem_info->size = PAGE_SIZE;
 
        return 0;
 
 clear_pa:
-       mem_info->pa = 0;
+       mem_info->dma = 0;
 remove_interrupter:
        xhci_sideband_remove_interrupter(uadev[card_num].sb);
 exit:
@@ -1340,7 +1340,7 @@ static int prepare_qmi_response(struct snd_usb_substream *subs,
        struct q6usb_offload *data;
        int pcm_dev_num;
        int card_num;
-       u8 *xfer_buf = NULL;
+       u8 *xfer_buf_cpu = NULL;
        int ret;
 
        pcm_dev_num = (req_msg->usb_token & QMI_STREAM_REQ_DEV_NUM_MASK) >> 8;
@@ -1409,7 +1409,7 @@ static int prepare_qmi_response(struct snd_usb_substream *subs,
 
        resp->speed_info_valid = 1;
 
-       ret = uaudio_transfer_buffer_setup(subs, xfer_buf, req_msg->xfer_buff_size,
+       ret = uaudio_transfer_buffer_setup(subs, xfer_buf_cpu, req_msg->xfer_buff_size,
                                           &resp->xhci_mem_info.xfer_buff);
        if (ret < 0) {
                ret = -ENOMEM;
@@ -1440,15 +1440,15 @@ static int prepare_qmi_response(struct snd_usb_substream *subs,
 
        /* cache intf specific info to use it for unmap and free xfer buf */
        uadev[card_num].info[info_idx].data_xfer_ring_va =
-                                       IOVA_MASK(resp->xhci_mem_info.tr_data.va);
+                                       IOVA_MASK(resp->xhci_mem_info.tr_data.iova);
        uadev[card_num].info[info_idx].data_xfer_ring_size = PAGE_SIZE;
        uadev[card_num].info[info_idx].sync_xfer_ring_va =
-                                       IOVA_MASK(resp->xhci_mem_info.tr_sync.va);
+                                       IOVA_MASK(resp->xhci_mem_info.tr_sync.iova);
        uadev[card_num].info[info_idx].sync_xfer_ring_size = PAGE_SIZE;
-       uadev[card_num].info[info_idx].xfer_buf_va =
-                                       IOVA_MASK(resp->xhci_mem_info.xfer_buff.va);
-       uadev[card_num].info[info_idx].xfer_buf_pa =
-                                       resp->xhci_mem_info.xfer_buff.pa;
+       uadev[card_num].info[info_idx].xfer_buf_iova =
+                                       IOVA_MASK(resp->xhci_mem_info.xfer_buff.iova);
+       uadev[card_num].info[info_idx].xfer_buf_dma =
+                                       resp->xhci_mem_info.xfer_buff.dma;
        uadev[card_num].info[info_idx].xfer_buf_size =
                                        resp->xhci_mem_info.xfer_buff.size;
        uadev[card_num].info[info_idx].data_ep_pipe = subs->data_endpoint ?
@@ -1459,7 +1459,7 @@ static int prepare_qmi_response(struct snd_usb_substream *subs,
                                                subs->data_endpoint->ep_num : 0;
        uadev[card_num].info[info_idx].sync_ep_idx = subs->sync_endpoint ?
                                                subs->sync_endpoint->ep_num : 0;
-       uadev[card_num].info[info_idx].xfer_buf = xfer_buf;
+       uadev[card_num].info[info_idx].xfer_buf_cpu = xfer_buf_cpu;
        uadev[card_num].info[info_idx].pcm_card_num = card_num;
        uadev[card_num].info[info_idx].pcm_dev_num = pcm_dev_num;
        uadev[card_num].info[info_idx].direction = subs->direction;
@@ -1477,13 +1477,13 @@ free_sec_ring:
 drop_sync_ep:
        if (subs->sync_endpoint) {
                uaudio_iommu_unmap(MEM_XFER_RING,
-                                  IOVA_MASK(resp->xhci_mem_info.tr_sync.va),
+                                  IOVA_MASK(resp->xhci_mem_info.tr_sync.iova),
                                   PAGE_SIZE, PAGE_SIZE);
                xhci_sideband_remove_endpoint(uadev[card_num].sb,
                        usb_pipe_endpoint(subs->dev, subs->sync_endpoint->pipe));
        }
 drop_data_ep:
-       uaudio_iommu_unmap(MEM_XFER_RING, IOVA_MASK(resp->xhci_mem_info.tr_data.va),
+       uaudio_iommu_unmap(MEM_XFER_RING, IOVA_MASK(resp->xhci_mem_info.tr_data.iova),
                           PAGE_SIZE, PAGE_SIZE);
        xhci_sideband_remove_endpoint(uadev[card_num].sb,
                        usb_pipe_endpoint(subs->dev, subs->data_endpoint->pipe));

diff --git a/sound/usb/qcom/usb_audio_qmi_v01.c b/sound/usb/qcom/usb_audio_qmi_v01.c
index 151ae7b591decde5cd1d448a6cb90162a18c9b90..50285761227746e3788f3711219f5d2948aa761e 100644 (file)
--- a/sound/usb/qcom/usb_audio_qmi_v01.c
+++ b/sound/usb/qcom/usb_audio_qmi_v01.c
@@ -14,7 +14,7 @@ static const struct qmi_elem_info mem_info_v01_ei[] = {
                .elem_size      = sizeof(u64),
                .array_type     = NO_ARRAY,
                .tlv_type       = 0,
-               .offset         = offsetof(struct mem_info_v01, va),
+               .offset         = offsetof(struct mem_info_v01, iova),
        },
        {
                .data_type      = QMI_UNSIGNED_8_BYTE,
@@ -22,7 +22,7 @@ static const struct qmi_elem_info mem_info_v01_ei[] = {
                .elem_size      = sizeof(u64),
                .array_type     = NO_ARRAY,
                .tlv_type       = 0,
-               .offset         = offsetof(struct mem_info_v01, pa),
+               .offset         = offsetof(struct mem_info_v01, dma),
        },
        {
                .data_type      = QMI_UNSIGNED_4_BYTE,

diff --git a/sound/usb/qcom/usb_audio_qmi_v01.h b/sound/usb/qcom/usb_audio_qmi_v01.h
index f2563537ed4036786dacdc4176b1d32b4c6f6e50..a1298d75d9f880da3f92bad49036b4e358813ba5 100644 (file)
--- a/sound/usb/qcom/usb_audio_qmi_v01.h
+++ b/sound/usb/qcom/usb_audio_qmi_v01.h
@@ -14,8 +14,8 @@
 #define QMI_UAUDIO_STREAM_IND_V01 0x0001
 
 struct mem_info_v01 {
-       u64 va;
-       u64 pa;
+       u64 iova;       /* mapped into sysdev */
+       u64 dma;        /* mapped into usb host */
        u32 size;
 };