Mega busdma API commit.

Add two new arguments to bus_dma_tag_create(): lockfunc and lockfuncarg.
Lockfunc allows a driver to provide a function for managing its locking
semantics while using busdma.  At the moment, this is used for the
asynchronous busdma_swi and callback mechanism.  Two lockfunc implementations
are provided: busdma_lock_mutex() performs standard mutex operations on the
mutex that is specified from lockfuncarg.  dftl_lock() is a panic
implementation and is defaulted to when NULL, NULL are passed to
bus_dma_tag_create().  The only time that NULL, NULL should ever be used is
when the driver ensures that bus_dmamap_load() will not be deferred.
Drivers that do not provide their own locking can pass
busdma_lock_mutex,&Giant args in order to preserve the former behaviour.

sparc64 and powerpc do not provide real busdma_swi functions, so this is
largely a noop on those platforms.  The busdma_swi on is64 is not properly
locked yet, so warnings will be emitted on this platform when busdma
callback deferrals happen.

If anyone gets panics or warnings from dflt_lock() being called, please
let me know right away.

Reviewed by:	tmm, gibbs

1 files changed, 4 insertions, 4 deletions

diff --git a/sys/dev/gem/if_gem.c b/sys/dev/gem/if_gem.c
index 6f1a3b1..8395215 100644
--- a/sys/dev/gem/if_gem.c
+++ b/sys/dev/gem/if_gem.c
@@ -133,13 +133,13 @@ gem_attach(sc)
 
 	error = bus_dma_tag_create(NULL, 1, 0, BUS_SPACE_MAXADDR_32BIT,
 	    BUS_SPACE_MAXADDR, NULL, NULL, MCLBYTES, GEM_NSEGS,
-	    BUS_SPACE_MAXSIZE_32BIT, 0, &sc->sc_pdmatag);
+	    BUS_SPACE_MAXSIZE_32BIT, 0, NULL, NULL, &sc->sc_pdmatag);
 	if (error)
 		return (error);
 
 	error = bus_dma_tag_create(sc->sc_pdmatag, 1, 0,
 	    BUS_SPACE_MAXADDR_32BIT, BUS_SPACE_MAXADDR, NULL, NULL, MAXBSIZE,
-	    1, BUS_SPACE_MAXSIZE_32BIT, BUS_DMA_ALLOCNOW,
+	    1, BUS_SPACE_MAXSIZE_32BIT, BUS_DMA_ALLOCNOW, NULL, NULL,
 	    &sc->sc_rdmatag);
 	if (error)
 		goto fail_ptag;
@@ -147,7 +147,7 @@ gem_attach(sc)
 	error = bus_dma_tag_create(sc->sc_pdmatag, 1, 0,
 	    BUS_SPACE_MAXADDR_32BIT, BUS_SPACE_MAXADDR, NULL, NULL,
 	    GEM_TD_BUFSIZE, GEM_NTXDESC, BUS_SPACE_MAXSIZE_32BIT,
-	    BUS_DMA_ALLOCNOW, &sc->sc_tdmatag);
+	    BUS_DMA_ALLOCNOW, NULL, NULL, &sc->sc_tdmatag);
 	if (error)
 		goto fail_rtag;
 
@@ -155,7 +155,7 @@ gem_attach(sc)
 	    BUS_SPACE_MAXADDR_32BIT, BUS_SPACE_MAXADDR, NULL, NULL,
 	    sizeof(struct gem_control_data), 1,
 	    sizeof(struct gem_control_data), BUS_DMA_ALLOCNOW,
-	    &sc->sc_cdmatag);
+	    busdma_lock_mutex, &Giant, &sc->sc_cdmatag);
 	if (error)
 		goto fail_ttag;