- Introduce a new busdma flag BUS_DMA_ZERO to request for zero'ed

  memory in bus_dmamem_alloc().  This is possible now that
  contigmalloc() supports the M_ZERO flag.
- Remove the locking of Giant around calls to contigmalloc() since
  contigmalloc() now grabs Giant itself.

13 files changed, 72 insertions, 44 deletions

diff --git a/sys/alpha/alpha/busdma_machdep.c b/sys/alpha/alpha/busdma_machdep.c
index d743e8d..279d3a6 100644
--- a/sys/alpha/alpha/busdma_machdep.c
+++ b/sys/alpha/alpha/busdma_machdep.c
@@ -413,24 +413,29 @@ int
 bus_dmamem_alloc(bus_dma_tag_t dmat, void** vaddr, int flags,
 		 bus_dmamap_t *mapp)
 {
+	int mflags;
+
+	if (flags & BUS_DMA_NOWAIT)
+		mflags = M_NOWAIT;
+	else
+		mflags = M_WAITOK;
+	if (flags & BUS_DMA_ZERO)
+		mflags |= M_ZERO;
+
 	/* If we succeed, no mapping/bouncing will be required */
 	*mapp = &nobounce_dmamap;
 
 	if ((dmat->maxsize <= PAGE_SIZE) && dmat->lowaddr >= ptoa(Maxmem)) {
-		*vaddr = malloc(dmat->maxsize, M_DEVBUF,
-				(flags & BUS_DMA_NOWAIT) ? M_NOWAIT : M_WAITOK);
+		*vaddr = malloc(dmat->maxsize, M_DEVBUF, mflags);
 	} else {
 		/*
 		 * XXX Use Contigmalloc until it is merged into this facility
 		 *     and handles multi-seg allocations.  Nobody is doing
 		 *     multi-seg allocations yet though.
 		 */
-		mtx_lock(&Giant);
-		*vaddr = contigmalloc(dmat->maxsize, M_DEVBUF,
-		    (flags & BUS_DMA_NOWAIT) ? M_NOWAIT : M_WAITOK,
+		*vaddr = contigmalloc(dmat->maxsize, M_DEVBUF, mflags,
 		    0ul, dmat->lowaddr, dmat->alignment? dmat->alignment : 1ul,
 		    dmat->boundary);
-		mtx_unlock(&Giant);
 	}
 	if (*vaddr == NULL)
 		return (ENOMEM);
@@ -894,13 +899,11 @@ alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages)
 
 		if (bpage == NULL)
 			break;
-		mtx_lock(&Giant);
 		bpage->vaddr = (vm_offset_t)contigmalloc(PAGE_SIZE, M_DEVBUF,
 							 M_NOWAIT, 0ul,
 							 dmat->lowaddr,
 							 PAGE_SIZE,
 							 dmat->boundary);
-		mtx_unlock(&Giant);
 		if (bpage->vaddr == 0) {
 			free(bpage, M_DEVBUF);
 			break;
diff --git a/sys/alpha/include/bus.h b/sys/alpha/include/bus.h
index 582484c..53eefd8 100644
--- a/sys/alpha/include/bus.h
+++ b/sys/alpha/include/bus.h
@@ -470,6 +470,7 @@ void busspace_generic_barrier(struct alpha_busspace *space,
 #define	BUS_DMA_NOWAIT		0x01	/* not safe to sleep */
 #define	BUS_DMA_ALLOCNOW	0x02	/* perform resource allocation now */
 #define	BUS_DMA_COHERENT	0x04	/* hint: map memory in a coherent way */
+#define	BUS_DMA_ZERO		0x08	/* allocate zero'ed memory */
 #define	BUS_DMA_ISA		0x10	/* map memory for ISA dma */
 #define	BUS_DMA_BUS2		0x20	/* placeholders for bus functions... */
 #define	BUS_DMA_BUS3		0x40
diff --git a/sys/amd64/amd64/busdma_machdep.c b/sys/amd64/amd64/busdma_machdep.c
index 2339641..058210b 100644
--- a/sys/amd64/amd64/busdma_machdep.c
+++ b/sys/amd64/amd64/busdma_machdep.c
@@ -390,25 +390,30 @@ int
 bus_dmamem_alloc(bus_dma_tag_t dmat, void** vaddr, int flags,
 		 bus_dmamap_t *mapp)
 {
+	int mflags;
+
+	if (flags & BUS_DMA_NOWAIT)
+		mflags = M_NOWAIT;
+	else
+		mflags = M_WAITOK;
+	if (flags & BUS_DMA_ZERO)
+		mflags |= M_ZERO;
+
 	/* If we succeed, no mapping/bouncing will be required */
 	*mapp = NULL;
 
 	if ((dmat->maxsize <= PAGE_SIZE) &&
 	    dmat->lowaddr >= ptoa((vm_paddr_t)Maxmem)) {
-		*vaddr = malloc(dmat->maxsize, M_DEVBUF,
-				(flags & BUS_DMA_NOWAIT) ? M_NOWAIT : M_WAITOK);
+		*vaddr = malloc(dmat->maxsize, M_DEVBUF, mflags);
 	} else {
 		/*
 		 * XXX Use Contigmalloc until it is merged into this facility
 		 *     and handles multi-seg allocations.  Nobody is doing
 		 *     multi-seg allocations yet though.
 		 */
-		mtx_lock(&Giant);
-		*vaddr = contigmalloc(dmat->maxsize, M_DEVBUF,
-		    (flags & BUS_DMA_NOWAIT) ? M_NOWAIT : M_WAITOK,
+		*vaddr = contigmalloc(dmat->maxsize, M_DEVBUF, mflags,
 		    0ul, dmat->lowaddr, dmat->alignment? dmat->alignment : 1ul,
 		    dmat->boundary);
-		mtx_unlock(&Giant);
 	}
 	if (*vaddr == NULL)
 		return (ENOMEM);
@@ -809,13 +814,11 @@ alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages)
 
 		if (bpage == NULL)
 			break;
-		mtx_lock(&Giant);
 		bpage->vaddr = (vm_offset_t)contigmalloc(PAGE_SIZE, M_DEVBUF,
 							 M_NOWAIT, 0ul,
 							 dmat->lowaddr,
 							 PAGE_SIZE,
 							 dmat->boundary);
-		mtx_unlock(&Giant);
 		if (bpage->vaddr == 0) {
 			free(bpage, M_DEVBUF);
 			break;
diff --git a/sys/amd64/include/bus_dma.h b/sys/amd64/include/bus_dma.h
index b0928f1..b9129e9 100644
--- a/sys/amd64/include/bus_dma.h
+++ b/sys/amd64/include/bus_dma.h
@@ -79,6 +79,7 @@
 #define	BUS_DMA_NOWAIT		0x01	/* not safe to sleep */
 #define	BUS_DMA_ALLOCNOW	0x02	/* perform resource allocation now */
 #define	BUS_DMA_COHERENT	0x04	/* hint map memory in a coherent way */
+#define	BUS_DMA_ZERO		0x08	/* allocate zero'ed memory */
 #define	BUS_DMA_BUS1		0x10	/* placeholders for bus functions... */
 #define	BUS_DMA_BUS2		0x20
 #define	BUS_DMA_BUS3		0x40
diff --git a/sys/i386/i386/busdma_machdep.c b/sys/i386/i386/busdma_machdep.c
index 5ebaa00..8bf5b0b 100644
--- a/sys/i386/i386/busdma_machdep.c
+++ b/sys/i386/i386/busdma_machdep.c
@@ -386,25 +386,30 @@ int
 bus_dmamem_alloc(bus_dma_tag_t dmat, void** vaddr, int flags,
 		 bus_dmamap_t *mapp)
 {
+	int mflags;
+
+	if (flags & BUS_DMA_NOWAIT)
+		mflags = M_NOWAIT;
+	else
+		mflags = M_WAITOK;
+	if (flags & BUS_DMA_ZERO)
+		mflags |= M_ZERO;
+
 	/* If we succeed, no mapping/bouncing will be required */
 	*mapp = NULL;
 
 	if ((dmat->maxsize <= PAGE_SIZE) &&
 	    dmat->lowaddr >= ptoa((vm_paddr_t)Maxmem)) {
-		*vaddr = malloc(dmat->maxsize, M_DEVBUF,
-				(flags & BUS_DMA_NOWAIT) ? M_NOWAIT : M_WAITOK);
+		*vaddr = malloc(dmat->maxsize, M_DEVBUF, mflags);
 	} else {
 		/*
 		 * XXX Use Contigmalloc until it is merged into this facility
 		 *     and handles multi-seg allocations.  Nobody is doing
 		 *     multi-seg allocations yet though.
 		 */
-		mtx_lock(&Giant);
-		*vaddr = contigmalloc(dmat->maxsize, M_DEVBUF,
-		    (flags & BUS_DMA_NOWAIT) ? M_NOWAIT : M_WAITOK,
+		*vaddr = contigmalloc(dmat->maxsize, M_DEVBUF, mflags,
 		    0ul, dmat->lowaddr, dmat->alignment? dmat->alignment : 1ul,
 		    dmat->boundary);
-		mtx_unlock(&Giant);
 	}
 	if (*vaddr == NULL)
 		return (ENOMEM);
@@ -805,13 +810,11 @@ alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages)
 
 		if (bpage == NULL)
 			break;
-		mtx_lock(&Giant);
 		bpage->vaddr = (vm_offset_t)contigmalloc(PAGE_SIZE, M_DEVBUF,
 							 M_NOWAIT, 0ul,
 							 dmat->lowaddr,
 							 PAGE_SIZE,
 							 dmat->boundary);
-		mtx_unlock(&Giant);
 		if (bpage->vaddr == 0) {
 			free(bpage, M_DEVBUF);
 			break;
diff --git a/sys/i386/include/bus_dma.h b/sys/i386/include/bus_dma.h
index 3539a33..9b75eae 100644
--- a/sys/i386/include/bus_dma.h
+++ b/sys/i386/include/bus_dma.h
@@ -79,6 +79,7 @@
 #define	BUS_DMA_NOWAIT		0x01	/* not safe to sleep */
 #define	BUS_DMA_ALLOCNOW	0x02	/* perform resource allocation now */
 #define	BUS_DMA_COHERENT	0x04	/* hint: map memory in a coherent way */
+#define	BUS_DMA_ZERO		0x08	/* allocate zero'ed memory */
 #define	BUS_DMA_BUS1		0x10	/* placeholders for bus functions... */
 #define	BUS_DMA_BUS2		0x20
 #define	BUS_DMA_BUS3		0x40
diff --git a/sys/ia64/ia64/busdma_machdep.c b/sys/ia64/ia64/busdma_machdep.c
index 231ac3b..29ade1f 100644
--- a/sys/ia64/ia64/busdma_machdep.c
+++ b/sys/ia64/ia64/busdma_machdep.c
@@ -413,24 +413,29 @@ int
 bus_dmamem_alloc(bus_dma_tag_t dmat, void** vaddr, int flags,
 		 bus_dmamap_t *mapp)
 {
+	int mflags;
+
+	if (flags & BUS_DMA_NOWAIT)
+		mflags = M_NOWAIT;
+	else
+		mflags = M_WAITOK;
+	if (flags & BUS_DMA_ZERO)
+		mflags |= M_ZERO;
+
 	/* If we succeed, no mapping/bouncing will be required */
 	*mapp = &nobounce_dmamap;
 
 	if ((dmat->maxsize <= PAGE_SIZE) && dmat->lowaddr >= ptoa(Maxmem)) {
-		*vaddr = malloc(dmat->maxsize, M_DEVBUF,
-				(flags & BUS_DMA_NOWAIT) ? M_NOWAIT : M_WAITOK);
+		*vaddr = malloc(dmat->maxsize, M_DEVBUF, mflags);
 	} else {
 		/*
 		 * XXX Use Contigmalloc until it is merged into this facility
 		 *     and handles multi-seg allocations.  Nobody is doing
 		 *     multi-seg allocations yet though.
 		 */
-		mtx_lock(&Giant);
-		*vaddr = contigmalloc(dmat->maxsize, M_DEVBUF,
-		    (flags & BUS_DMA_NOWAIT) ? M_NOWAIT : M_WAITOK,
+		*vaddr = contigmalloc(dmat->maxsize, M_DEVBUF, mflags,
 		    0ul, dmat->lowaddr, dmat->alignment? dmat->alignment : 1ul,
 		    dmat->boundary);
-		mtx_unlock(&Giant);
 	}
 	if (*vaddr == NULL)
 		return (ENOMEM);
@@ -896,13 +901,11 @@ alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages)
 
 		if (bpage == NULL)
 			break;
-		mtx_lock(&Giant);
 		bpage->vaddr = (vm_offset_t)contigmalloc(PAGE_SIZE, M_DEVBUF,
 							 M_NOWAIT, 0ul,
 							 dmat->lowaddr,
 							 PAGE_SIZE,
 							 dmat->boundary);
-		mtx_unlock(&Giant);
 		if (bpage->vaddr == 0) {
 			free(bpage, M_DEVBUF);
 			break;
diff --git a/sys/ia64/include/bus.h b/sys/ia64/include/bus.h
index 7a5c0f4..0db84a4 100644
--- a/sys/ia64/include/bus.h
+++ b/sys/ia64/include/bus.h
@@ -852,6 +852,7 @@ bus_space_copy_region_8(bus_space_tag_t bst, bus_space_handle_t bsh1,
 #define	BUS_DMA_NOWAIT		0x01	/* not safe to sleep */
 #define	BUS_DMA_ALLOCNOW	0x02	/* perform resource allocation now */
 #define	BUS_DMA_COHERENT	0x04	/* hint: map memory in a coherent way */
+#define	BUS_DMA_ZERO		0x08	/* allocate zero'ed memory */
 #define	BUS_DMA_ISA		0x10	/* map memory for ISA dma */
 #define	BUS_DMA_BUS2		0x20	/* placeholders for bus functions... */
 #define	BUS_DMA_BUS3		0x40
diff --git a/sys/powerpc/include/bus.h b/sys/powerpc/include/bus.h
index 3ee2de5..bb5f357 100644
--- a/sys/powerpc/include/bus.h
+++ b/sys/powerpc/include/bus.h
@@ -744,6 +744,7 @@ bus_space_set_region_stream_4(bus_space_tag_t tag, bus_space_handle_t bsh,
 #define	BUS_DMA_NOWAIT		0x01	/* not safe to sleep */
 #define	BUS_DMA_ALLOCNOW	0x02	/* perform resource allocation now */
 #define	BUS_DMA_COHERENT	0x04	/* hint: map memory DMA coherent */
+#define	BUS_DMA_ZERO		0x08	/* allocate zero'ed memory */
 #define	BUS_DMA_BUS1		0x10	/* placeholders for bus functions... */
 #define	BUS_DMA_BUS2		0x20
 #define	BUS_DMA_BUS3		0x40
diff --git a/sys/powerpc/powerpc/busdma_machdep.c b/sys/powerpc/powerpc/busdma_machdep.c
index f3ef3e3..829d29ab 100644
--- a/sys/powerpc/powerpc/busdma_machdep.c
+++ b/sys/powerpc/powerpc/busdma_machdep.c
@@ -254,23 +254,28 @@ int
 bus_dmamem_alloc(bus_dma_tag_t dmat, void** vaddr, int flags,
                  bus_dmamap_t *mapp)
 {
+	int mflags;
+
+	if (flags & BUS_DMA_NOWAIT)
+		mflags = M_NOWAIT;
+	else
+		mflags = M_WAITOK;
+	if (flags & BUS_DMA_ZERO)
+		mflags |= M_ZERO;
+
         *mapp = NULL;
 	
         if (dmat->maxsize <= PAGE_SIZE) {
-                *vaddr = malloc(dmat->maxsize, M_DEVBUF,
-                             (flags & BUS_DMA_NOWAIT) ? M_NOWAIT : M_WAITOK);
+                *vaddr = malloc(dmat->maxsize, M_DEVBUF, mflags);
         } else {
                 /*
                  * XXX Use Contigmalloc until it is merged into this facility
                  *     and handles multi-seg allocations.  Nobody is doing
                  *     multi-seg allocations yet though.
                  */
-		mtx_lock(&Giant);
-                *vaddr = contigmalloc(dmat->maxsize, M_DEVBUF,
-                    (flags & BUS_DMA_NOWAIT) ? M_NOWAIT : M_WAITOK,
+                *vaddr = contigmalloc(dmat->maxsize, M_DEVBUF, mflags,
                     0ul, dmat->lowaddr, dmat->alignment? dmat->alignment : 1ul,
                     dmat->boundary);
-		mtx_unlock(&Giant);
         }
 
         if (*vaddr == NULL)
diff --git a/sys/sparc64/include/bus.h b/sys/sparc64/include/bus.h
index f97c13b..90d33ab 100644
--- a/sys/sparc64/include/bus.h
+++ b/sys/sparc64/include/bus.h
@@ -900,6 +900,7 @@ memsetw(void *d, int val, size_t size)
 #define	BUS_DMA_NOWAIT		0x001	/* not safe to sleep */
 #define	BUS_DMA_ALLOCNOW	0x002	/* perform resource allocation now */
 #define	BUS_DMA_COHERENT	0x004	/* hint: map memory in a coherent way */
+#define	BUS_DMA_ZERO		0x008	/* allocate zero'ed memory */
 #define	BUS_DMA_BUS1		0x010
 #define	BUS_DMA_BUS2		0x020
 #define	BUS_DMA_BUS3		0x040
diff --git a/sys/sparc64/sparc64/bus_machdep.c b/sys/sparc64/sparc64/bus_machdep.c
index 5843b73..e0655e2 100644
--- a/sys/sparc64/sparc64/bus_machdep.c
+++ b/sys/sparc64/sparc64/bus_machdep.c
@@ -612,23 +612,27 @@ static int
 nexus_dmamem_alloc(bus_dma_tag_t dmat, void **vaddr, int flags,
     bus_dmamap_t *mapp)
 {
+	int mflags;
+
+	if (flags & BUS_DMA_NOWAIT)
+		mflags = M_NOWAIT;
+	else
+		mflags = M_WAITOK;
+	if (flags & BUS_DMA_ZERO)
+		mflags |= M_ZERO;
 
 	if ((dmat->dt_maxsize <= PAGE_SIZE)) {
-		*vaddr = malloc(dmat->dt_maxsize, M_DEVBUF,
-		    (flags & BUS_DMA_NOWAIT) ? M_NOWAIT : M_WAITOK);
+		*vaddr = malloc(dmat->dt_maxsize, M_DEVBUF, mflags);
 	} else {
 		/*
 		 * XXX: Use contigmalloc until it is merged into this facility
 		 * and handles multi-seg allocations.  Nobody is doing multi-seg
 		 * allocations yet though.
 		 */
-		mtx_lock(&Giant);
-		*vaddr = contigmalloc(dmat->dt_maxsize, M_DEVBUF,
-		    (flags & BUS_DMA_NOWAIT) ? M_NOWAIT : M_WAITOK,
+		*vaddr = contigmalloc(dmat->dt_maxsize, M_DEVBUF, mflags,
 		    0ul, dmat->dt_lowaddr,
 		    dmat->dt_alignment ? dmat->dt_alignment : 1UL,
 		    dmat->dt_boundary);
-		mtx_unlock(&Giant);
 	}
 	if (*vaddr == NULL)
 		return (ENOMEM);
diff --git a/sys/sys/bus_dma.h b/sys/sys/bus_dma.h
index 3539a33..9b75eae 100644
--- a/sys/sys/bus_dma.h
+++ b/sys/sys/bus_dma.h
@@ -79,6 +79,7 @@
 #define	BUS_DMA_NOWAIT		0x01	/* not safe to sleep */
 #define	BUS_DMA_ALLOCNOW	0x02	/* perform resource allocation now */
 #define	BUS_DMA_COHERENT	0x04	/* hint: map memory in a coherent way */
+#define	BUS_DMA_ZERO		0x08	/* allocate zero'ed memory */
 #define	BUS_DMA_BUS1		0x10	/* placeholders for bus functions... */
 #define	BUS_DMA_BUS2		0x20
 #define	BUS_DMA_BUS3		0x40