PCI: epf-test: Simplify DMA support checks

There is no need to have each read, write and copy test functions check
for the FLAG_USE_DMA flag against the DMA support status indicated by
epf_test->dma_supported. Move this test to the command handler function
pci_epf_test_cmd_handler() to check once for all cases.

Link: https://lore.kernel.org/r/20230415023542.77601-13-dlemoal@kernel.org
Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
Signed-off-by: Lorenzo Pieralisi <lpieralisi@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Manivannan Sadhasivam <mani@kernel.org>

diff --git a/drivers/pci/endpoint/functions/pci-epf-test.c b/drivers/pci/endpoint/functions/pci-epf-test.c
index e528b09..909e3e8 100644 (file)
--- a/drivers/pci/endpoint/functions/pci-epf-test.c
+++ b/drivers/pci/endpoint/functions/pci-epf-test.c
@@ -329,7 +329,6 @@ static void pci_epf_test_copy(struct pci_epf_test *epf_test,
                              struct pci_epf_test_reg *reg)
 {
        int ret;
-       bool use_dma;
        void __iomem *src_addr;
        void __iomem *dst_addr;
        phys_addr_t src_phys_addr;
@@ -372,14 +371,7 @@ static void pci_epf_test_copy(struct pci_epf_test *epf_test,
        }
 
        ktime_get_ts64(&start);
-       use_dma = !!(reg->flags & FLAG_USE_DMA);
-       if (use_dma) {
-               if (!epf_test->dma_supported) {
-                       dev_err(dev, "Cannot transfer data using DMA\n");
-                       ret = -EINVAL;
-                       goto err_map_addr;
-               }
-
+       if (reg->flags & FLAG_USE_DMA) {
                if (epf_test->dma_private) {
                        dev_err(dev, "Cannot transfer data using DMA\n");
                        ret = -EINVAL;
@@ -405,7 +397,8 @@ static void pci_epf_test_copy(struct pci_epf_test *epf_test,
                kfree(buf);
        }
        ktime_get_ts64(&end);
-       pci_epf_test_print_rate("COPY", reg->size, &start, &end, use_dma);
+       pci_epf_test_print_rate("COPY", reg->size, &start, &end,
+                               reg->flags & FLAG_USE_DMA);
 
 err_map_addr:
        pci_epc_unmap_addr(epc, epf->func_no, epf->vfunc_no, dst_phys_addr);
@@ -433,7 +426,6 @@ static void pci_epf_test_read(struct pci_epf_test *epf_test,
        void __iomem *src_addr;
        void *buf;
        u32 crc32;
-       bool use_dma;
        phys_addr_t phys_addr;
        phys_addr_t dst_phys_addr;
        struct timespec64 start, end;
@@ -464,14 +456,7 @@ static void pci_epf_test_read(struct pci_epf_test *epf_test,
                goto err_map_addr;
        }
 
-       use_dma = !!(reg->flags & FLAG_USE_DMA);
-       if (use_dma) {
-               if (!epf_test->dma_supported) {
-                       dev_err(dev, "Cannot transfer data using DMA\n");
-                       ret = -EINVAL;
-                       goto err_dma_map;
-               }
-
+       if (reg->flags & FLAG_USE_DMA) {
                dst_phys_addr = dma_map_single(dma_dev, buf, reg->size,
                                               DMA_FROM_DEVICE);
                if (dma_mapping_error(dma_dev, dst_phys_addr)) {
@@ -496,7 +481,8 @@ static void pci_epf_test_read(struct pci_epf_test *epf_test,
                ktime_get_ts64(&end);
        }
 
-       pci_epf_test_print_rate("READ", reg->size, &start, &end, use_dma);
+       pci_epf_test_print_rate("READ", reg->size, &start, &end,
+                               reg->flags & FLAG_USE_DMA);
 
        crc32 = crc32_le(~0, buf, reg->size);
        if (crc32 != reg->checksum)
@@ -524,7 +510,6 @@ static void pci_epf_test_write(struct pci_epf_test *epf_test,
        int ret;
        void __iomem *dst_addr;
        void *buf;
-       bool use_dma;
        phys_addr_t phys_addr;
        phys_addr_t src_phys_addr;
        struct timespec64 start, end;
@@ -558,14 +543,7 @@ static void pci_epf_test_write(struct pci_epf_test *epf_test,
        get_random_bytes(buf, reg->size);
        reg->checksum = crc32_le(~0, buf, reg->size);
 
-       use_dma = !!(reg->flags & FLAG_USE_DMA);
-       if (use_dma) {
-               if (!epf_test->dma_supported) {
-                       dev_err(dev, "Cannot transfer data using DMA\n");
-                       ret = -EINVAL;
-                       goto err_dma_map;
-               }
-
+       if (reg->flags & FLAG_USE_DMA) {
                src_phys_addr = dma_map_single(dma_dev, buf, reg->size,
                                               DMA_TO_DEVICE);
                if (dma_mapping_error(dma_dev, src_phys_addr)) {
@@ -592,7 +570,8 @@ static void pci_epf_test_write(struct pci_epf_test *epf_test,
                ktime_get_ts64(&end);
        }
 
-       pci_epf_test_print_rate("WRITE", reg->size, &start, &end, use_dma);
+       pci_epf_test_print_rate("WRITE", reg->size, &start, &end,
+                               reg->flags & FLAG_USE_DMA);
 
        /*
         * wait 1ms inorder for the write to complete. Without this delay L3
@@ -679,6 +658,12 @@ static void pci_epf_test_cmd_handler(struct work_struct *work)
        WRITE_ONCE(reg->command, 0);
        WRITE_ONCE(reg->status, 0);
 
+       if ((READ_ONCE(reg->flags) & FLAG_USE_DMA) &&
+           !epf_test->dma_supported) {
+               dev_err(dev, "Cannot transfer data using DMA\n");
+               goto reset_handler;
+       }
+
        if (reg->irq_type > IRQ_TYPE_MSIX) {
                dev_err(dev, "Failed to detect IRQ type\n");
                goto reset_handler;