On Fri, Feb 04, 2011 at 01:32:55AM +0200, Eduard - Gabriel Munteanu wrote:
This introduces replacements for memory access functions like cpu_physical_memory_read(). The new interface can handle address translation and access checking through an IOMMU.
Signed-off-by: Eduard - Gabriel Munteanu eduard.munteanu@linux360.ro
Makefile.target | 2 +- hw/dma_rw.c | 124 +++++++++++++++++++++++++++++++++++++++++++ hw/dma_rw.h | 157 +++++++++++++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 282 insertions(+), 1 deletions(-) create mode 100644 hw/dma_rw.c create mode 100644 hw/dma_rw.h
diff --git a/Makefile.target b/Makefile.target index e15b1c4..e5817ab 100644 --- a/Makefile.target +++ b/Makefile.target @@ -218,7 +218,7 @@ obj-i386-y += cirrus_vga.o apic.o ioapic.o piix_pci.o obj-i386-y += vmmouse.o vmport.o hpet.o applesmc.o obj-i386-y += device-hotplug.o pci-hotplug.o smbios.o wdt_ib700.o obj-i386-y += debugcon.o multiboot.o -obj-i386-y += pc_piix.o +obj-i386-y += pc_piix.o dma_rw.o obj-i386-$(CONFIG_SPICE) += qxl.o qxl-logger.o qxl-render.o
# shared objects diff --git a/hw/dma_rw.c b/hw/dma_rw.c new file mode 100644 index 0000000..ef8e7f8 --- /dev/null +++ b/hw/dma_rw.c @@ -0,0 +1,124 @@ +/*
- Generic DMA memory access interface.
- Copyright (c) 2011 Eduard - Gabriel Munteanu
- Permission is hereby granted, free of charge, to any person obtaining a copy
- of this software and associated documentation files (the "Software"), to deal
- in the Software without restriction, including without limitation the rights
- to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
- copies of the Software, and to permit persons to whom the Software is
- furnished to do so, subject to the following conditions:
- The above copyright notice and this permission notice shall be included in
- all copies or substantial portions of the Software.
- THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
- THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
- LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
- OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
- THE SOFTWARE.
- */
+#include "dma_rw.h" +#include "range.h"
+static void dma_register_memory_map(DMADevice *dev,
dma_addr_t addr,dma_addr_t len,target_phys_addr_t paddr,DMAInvalidateMapFunc *invalidate,void *invalidate_opaque)+{
- DMAMemoryMap *map;
- map = qemu_malloc(sizeof(DMAMemoryMap));
- map->addr = addr;
- map->len = len;
- map->paddr = paddr;
- map->invalidate = invalidate;
- map->invalidate_opaque = invalidate_opaque;
- QLIST_INSERT_HEAD(&dev->mmu->memory_maps, map, list);
+}
+static void dma_unregister_memory_map(DMADevice *dev,
target_phys_addr_t paddr,dma_addr_t len)+{
- DMAMemoryMap *map;
- QLIST_FOREACH(map, &dev->mmu->memory_maps, list) {
if (map->paddr == paddr && map->len == len) {QLIST_REMOVE(map, list);free(map);}- }
+}
+void dma_invalidate_memory_range(DMADevice *dev,
dma_addr_t addr,dma_addr_t len)+{
- DMAMemoryMap *map;
- QLIST_FOREACH(map, &dev->mmu->memory_maps, list) {
if (ranges_overlap(addr, len, map->addr, map->len)) {map->invalidate(map->invalidate_opaque);QLIST_REMOVE(map, list);free(map);}- }
+}
+void *dma_memory_map(DMADevice *dev,
DMAInvalidateMapFunc *cb,void *opaque,dma_addr_t addr,dma_addr_t *len,int is_write)+{
- int err;
- target_phys_addr_t paddr, plen;
- if (!dev || !dev->mmu) {
return cpu_physical_memory_map(addr, len, is_write);- }
- plen = *len;
- err = dev->mmu->translate(dev, addr, &paddr, &plen, is_write);
- if (err) {
return NULL;- }
- /*
* If this is true, the virtual region is contiguous,* but the translated physical region isn't. We just* clamp *len, much like cpu_physical_memory_map() does.*/- if (plen < *len) {
*len = plen;- }
- /* We treat maps as remote TLBs to cope with stuff like AIO. */
- if (cb) {
dma_register_memory_map(dev, addr, *len, paddr, cb, opaque);- }
- return cpu_physical_memory_map(paddr, len, is_write);
+}
+void dma_memory_unmap(DMADevice *dev,
void *buffer,dma_addr_t len,int is_write,dma_addr_t access_len)+{
- cpu_physical_memory_unmap(buffer, len, is_write, access_len);
- if (dev && dev->mmu) {
dma_unregister_memory_map(dev, (target_phys_addr_t) buffer, len);- }
+}
diff --git a/hw/dma_rw.h b/hw/dma_rw.h new file mode 100644 index 0000000..bc93511 --- /dev/null +++ b/hw/dma_rw.h @@ -0,0 +1,157 @@ +#ifndef DMA_RW_H +#define DMA_RW_H
+#include "qemu-common.h"
+typedef uint64_t dma_addr_t;
+typedef struct DMAMmu DMAMmu; +typedef struct DMADevice DMADevice; +typedef struct DMAMemoryMap DMAMemoryMap;
+typedef int DMATranslateFunc(DMADevice *dev,
dma_addr_t addr,dma_addr_t *paddr,dma_addr_t *len,int is_write);
So len is in/out here which is a bit confusing, and apparently not documented until you look at the usage. I also don't think it needs to be dma_addr_t - it's not an address. I don't believe we ever need to translate more than 2G in one go: how about returning the length on success, negative on error?
Or add a comment.
+typedef void DMAInvalidateMapFunc(void *);
+struct DMAMmu {
- DeviceState *iommu;
- DMATranslateFunc *translate;
- QLIST_HEAD(memory_maps, DMAMemoryMap) memory_maps;
+};
+struct DMADevice {
- DMAMmu *mmu;
+};
+struct DMAMemoryMap {
- dma_addr_t addr;
- dma_addr_t len;
- target_phys_addr_t paddr;
- DMAInvalidateMapFunc *invalidate;
- void *invalidate_opaque;
- QLIST_ENTRY(DMAMemoryMap) list;
+};
+static inline void dma_memory_rw(DMADevice *dev,
dma_addr_t addr,void *buf,dma_addr_t len,int is_write)+{
- dma_addr_t paddr, plen;
- int err;
- /*
* Fast-path non-iommu.* More importantly, makes it obvious what this function does.*/- if (!dev || !dev->mmu) {
cpu_physical_memory_rw(addr, buf, plen, is_write);return;- }
- while (len) {
err = dev->mmu->translate(dev, addr, &paddr, &plen, is_write);if (err) {return;}/* The translation might be valid for larger regions. */if (plen > len) {plen = len;}cpu_physical_memory_rw(paddr, buf, plen, is_write);len -= plen;addr += plen;buf += plen;- }
+}
+static inline void dma_memory_read(DMADevice *dev,
dma_addr_t addr,void *buf,dma_addr_t len)+{
- dma_memory_rw(dev, addr, buf, len, 0);
+}
+static inline void dma_memory_write(DMADevice *dev,
dma_addr_t addr,const void *buf,dma_addr_t len)+{
- dma_memory_rw(dev, addr, (void *) buf, len, 1);
+}
+void *dma_memory_map(DMADevice *dev,
DMAInvalidateMapFunc *cb,void *opaque,dma_addr_t addr,dma_addr_t *len,int is_write);+void dma_memory_unmap(DMADevice *dev,
void *buffer,dma_addr_t len,int is_write,dma_addr_t access_len);+void dma_invalidate_memory_range(DMADevice *dev,
dma_addr_t addr,dma_addr_t len);+#define DEFINE_DMA_LD(suffix, size) \ +static inline uint##size##_t \ +dma_ld##suffix(DMADevice *dev, dma_addr_t addr) \ +{ \
- int err; \
- dma_addr_t paddr, plen; \
\- if (!dev || !dev->mmu) { \
return ld##suffix##_phys(addr); \- } \
\- err = dev->mmu->translate(dev, addr, &paddr, &plen, 0); \
- if (err || (plen < size / 8)) \
return 0; \\- return ld##suffix##_phys(paddr); \
+}
+#define DEFINE_DMA_ST(suffix, size) \ +static inline void \ +dma_st##suffix(DMADevice *dev, dma_addr_t addr, uint##size##_t val) \ +{ \
- int err; \
- target_phys_addr_t paddr, plen; \
\- if (!dev || !dev->mmu) { \
st##suffix##_phys(addr, val); \return; \- } \
- err = dev->mmu->translate(dev, addr, &paddr, &plen, 1); \
- if (err || (plen < size / 8)) \
return; \\- st##suffix##_phys(paddr, val); \
+}
+DEFINE_DMA_LD(ub, 8) +DEFINE_DMA_LD(uw, 16) +DEFINE_DMA_LD(l, 32) +DEFINE_DMA_LD(q, 64)
+DEFINE_DMA_ST(b, 8) +DEFINE_DMA_ST(w, 16) +DEFINE_DMA_ST(l, 32) +DEFINE_DMA_ST(q, 64)
+#endif
I am guessing the assumption is that address is size-aligned (which is right) so translation will fail for all addresses or pass for all of them. But in that case, assert() is better?
-- 1.7.3.4
-
Michael S. Tsirkin