On 11/14/24 14:58, Mark Kettenis wrote:
>> Date: Thu, 14 Nov 2024 14:46:21 +0000
>> From: David Hill <dhill@mindcry.org>
>>
>> Hello -
>>
>> uvm_km_kmemalloc_pla has 3 users: bce(4), envy(4), and malloc.
>>
>> I have attempted a conversion to km_alloc for bce(4), but I lack the
>> hardware to test.  If anyone has bce(4), could you please test?
> 
> This should really use bus_dmamem_alloc_range(9).  I don't think we
> had that interface back when the driver was changed to use
> uvm_km_kmemalloc_pla().
> 

My attempt at the conversion:

Index: dev/pci/if_bce.c
===================================================================
RCS file: /cvs/src/sys/dev/pci/if_bce.c,v
diff -u -p -r1.57 if_bce.c
--- dev/pci/if_bce.c	31 Aug 2024 16:23:09 -0000	1.57
+++ dev/pci/if_bce.c	15 Nov 2024 15:58:18 -0000
@@ -188,8 +188,8 @@ bce_attach(struct device *parent, struct
  	pci_intr_handle_t ih;
  	const char *intrstr = NULL;
  	caddr_t kva;
-	bus_dma_segment_t seg;
-	int rseg;
+	bus_dma_segment_t seg, dseg;
+	int rseg, drseg;
  	struct ifnet *ifp;
  	pcireg_t memtype;
  	bus_addr_t memaddr;
@@ -249,10 +249,19 @@ bce_attach(struct device *parent, struct
  	bce_reset(sc);

  	/* Create the data DMA region and maps. */
-	if ((sc->bce_data = (caddr_t)uvm_km_kmemalloc_pla(kernel_map,
-	    uvm.kernel_object, (BCE_NTXDESC + BCE_NRXDESC) * MCLBYTES, 0,
-	    UVM_KMF_NOWAIT, 0, (paddr_t)(0x40000000 - 1), 0, 0, 1)) == NULL) {
-		printf(": unable to alloc space for ring");
+	if ((error = bus_dmamem_alloc_range(sc->bce_dmatag,
+	    (BCE_NTXDESC + BCE_NRXDESC) * MCLBYTES, 0, 0, &dseg, 1, &drseg,
+	    BUS_DMA_NOWAIT, (bus_addr_t)0,
+	    (bus_addr_t)(0x40000000 - 1))) != 0) {
+		printf(": unable to alloc space for data, error = %d", error);
+		return;
+	}
+
+	if ((error = bus_dmamem_map(sc->bce_dmatag, &dseg, drseg,
+	    (BCE_NTXDESC + BCE_NRXDESC) * MCLBYTES, &sc->bce_data,
+	    BUS_DMA_NOWAIT))) {
+		printf(": unable to map data, error = %d\n", error);
+		bus_dmamem_free(sc->bce_dmatag, &dseg, drseg);
  		return;
  	}

@@ -261,8 +270,7 @@ bce_attach(struct device *parent, struct
  	    1, BCE_NRXDESC * MCLBYTES, 0, BUS_DMA_NOWAIT | BUS_DMA_ALLOCNOW,
  	    &sc->bce_rxdata_map))) {
  		printf(": unable to create ring DMA map, error = %d\n", error);
-		uvm_km_free(kernel_map, (vaddr_t)sc->bce_data,
-		    (BCE_NTXDESC + BCE_NRXDESC) * MCLBYTES);
+		bus_dmamem_free(sc->bce_dmatag, &dseg, drseg);
  		return;
  	}

@@ -270,9 +278,8 @@ bce_attach(struct device *parent, struct
  	if (bus_dmamap_load(sc->bce_dmatag, sc->bce_rxdata_map, sc->bce_data,
  	    BCE_NRXDESC * MCLBYTES, NULL, BUS_DMA_READ | BUS_DMA_NOWAIT)) {
  		printf(": unable to load rx ring DMA map\n");
-		uvm_km_free(kernel_map, (vaddr_t)sc->bce_data,
-		    (BCE_NTXDESC + BCE_NRXDESC) * MCLBYTES);
  		bus_dmamap_destroy(sc->bce_dmatag, sc->bce_rxdata_map);
+		bus_dmamem_free(sc->bce_dmatag, &dseg, drseg);
  		return;
  	}

@@ -314,10 +321,9 @@ bce_attach(struct device *parent, struct
  	    (bus_addr_t)0, (bus_addr_t)0x3fffffff))) {
  		printf(": unable to alloc space for ring descriptors, "
  		    "error = %d\n", error);
-		uvm_km_free(kernel_map, (vaddr_t)sc->bce_data,
-		    (BCE_NTXDESC + BCE_NRXDESC) * MCLBYTES);
  		bus_dmamap_destroy(sc->bce_dmatag, sc->bce_rxdata_map);
  		bus_dmamap_destroy(sc->bce_dmatag, sc->bce_txdata_map);
+		bus_dmamem_free(sc->bce_dmatag, &dseg, drseg);
  		return;
  	}

@@ -325,11 +331,10 @@ bce_attach(struct device *parent, struct
  	if ((error = bus_dmamem_map(sc->bce_dmatag, &seg, rseg,
  	    2 * PAGE_SIZE, &kva, BUS_DMA_NOWAIT))) {
  		printf(": unable to map DMA buffers, error = %d\n", error);
-		uvm_km_free(kernel_map, (vaddr_t)sc->bce_data,
-		    (BCE_NTXDESC + BCE_NRXDESC) * MCLBYTES);
  		bus_dmamap_destroy(sc->bce_dmatag, sc->bce_rxdata_map);
  		bus_dmamap_destroy(sc->bce_dmatag, sc->bce_txdata_map);
  		bus_dmamem_free(sc->bce_dmatag, &seg, rseg);
+		bus_dmamem_free(sc->bce_dmatag, &dseg, drseg);
  		return;
  	}

@@ -337,11 +342,10 @@ bce_attach(struct device *parent, struct
  	if ((error = bus_dmamap_create(sc->bce_dmatag, 2 * PAGE_SIZE, 1,
  	    2 * PAGE_SIZE, 0, BUS_DMA_NOWAIT, &sc->bce_ring_map))) {
  		printf(": unable to create ring DMA map, error = %d\n", error);
-		uvm_km_free(kernel_map, (vaddr_t)sc->bce_data,
-		    (BCE_NTXDESC + BCE_NRXDESC) * MCLBYTES);
  		bus_dmamap_destroy(sc->bce_dmatag, sc->bce_rxdata_map);
  		bus_dmamap_destroy(sc->bce_dmatag, sc->bce_txdata_map);
  		bus_dmamem_free(sc->bce_dmatag, &seg, rseg);
+		bus_dmamem_free(sc->bce_dmatag, &dseg, drseg);
  		return;
  	}

@@ -349,12 +353,11 @@ bce_attach(struct device *parent, struct
  	if (bus_dmamap_load(sc->bce_dmatag, sc->bce_ring_map, kva,
  	    2 * PAGE_SIZE, NULL, BUS_DMA_NOWAIT)) {
  		printf(": unable to load ring DMA map\n");
-		uvm_km_free(kernel_map, (vaddr_t)sc->bce_data,
-		    (BCE_NTXDESC + BCE_NRXDESC) * MCLBYTES);
  		bus_dmamap_destroy(sc->bce_dmatag, sc->bce_rxdata_map);
  		bus_dmamap_destroy(sc->bce_dmatag, sc->bce_txdata_map);
  		bus_dmamap_destroy(sc->bce_dmatag, sc->bce_ring_map);
  		bus_dmamem_free(sc->bce_dmatag, &seg, rseg);
+		bus_dmamem_free(sc->bce_dmatag, &dseg, drseg);
  		return;
  	}