dma: use per-device dma_arenas for dedicated devices
This commit adds the plumbing for picking a dma_arena for a device,
instead of assuming the default physical pages arena.
Future commits will add the ability to create and set a process's
user_pages arena.
Signed-off-by: Barret Rhoden <brho@cs.berkeley.edu>
diff --git a/kern/include/dma.h b/kern/include/dma.h
index 8343dec..6ed7db6 100644
--- a/kern/include/dma.h
+++ b/kern/include/dma.h
@@ -9,6 +9,7 @@
#pragma once
#include <arena.h>
+#include <arch/pci.h>
typedef physaddr_t dma_addr_t;
@@ -20,6 +21,7 @@
/* Default arena: basically just physical pages */
extern struct dma_arena dma_phys_pages;
+struct dma_arena *dev_to_dma_arena(struct device *d);
void dma_arena_init(void);
@@ -31,7 +33,7 @@
size_t size);
/* Compatible with Linux's DMA pool */
-struct dma_pool *dma_pool_create(const char *name, void *dev,
+struct dma_pool *dma_pool_create(const char *name, struct device *dev,
size_t size, size_t align, size_t allocation);
void dma_pool_destroy(struct dma_pool *pool);
void *dma_pool_alloc(struct dma_pool *pool, int mem_flags, dma_addr_t *handle);
diff --git a/kern/include/env.h b/kern/include/env.h
index dba5378..3689106 100644
--- a/kern/include/env.h
+++ b/kern/include/env.h
@@ -22,6 +22,7 @@
#include <ns.h>
#include <arch/vmm/vmm.h>
#include <arch/pci.h>
+#include <dma.h>
TAILQ_HEAD(vcore_tailq, vcore);
/* 'struct proc_list' declared in sched.h (not ideal...) */
@@ -121,6 +122,7 @@
struct strace *strace;
struct pcidev_tq pci_devices; /* for device passthru */
TAILQ_ENTRY(proc) iommu_link;
+ struct dma_arena *user_pages;
};
/* Til we remove all Env references */
diff --git a/kern/include/linux_compat.h b/kern/include/linux_compat.h
index bc92122..b331334 100644
--- a/kern/include/linux_compat.h
+++ b/kern/include/linux_compat.h
@@ -126,19 +126,19 @@
static inline void *dma_alloc_coherent(struct device *dev, size_t size,
dma_addr_t *dma_handle, int gfp)
{
- return dma_arena_zalloc(&dma_phys_pages, size, dma_handle, gfp);
+ return dma_arena_zalloc(dev_to_dma_arena(dev), size, dma_handle, gfp);
}
static inline void *dma_zalloc_coherent(struct device *dev, size_t size,
dma_addr_t *dma_handle, int gfp)
{
- return dma_arena_zalloc(&dma_phys_pages, size, dma_handle, gfp);
+ return dma_arena_zalloc(dev_to_dma_arena(dev), size, dma_handle, gfp);
}
static inline void dma_free_coherent(struct device *dev, size_t size,
void *cpu_addr, dma_addr_t dma_handle)
{
- dma_arena_free(&dma_phys_pages, cpu_addr, dma_handle, size);
+ dma_arena_free(dev_to_dma_arena(dev), cpu_addr, dma_handle, size);
}
#define dma_map_single(dev, addr, size, direction) \
diff --git a/kern/src/dma.c b/kern/src/dma.c
index fcad42d..f4293e4 100644
--- a/kern/src/dma.c
+++ b/kern/src/dma.c
@@ -54,6 +54,23 @@
* xalloc, and maybe more flexibility. */
struct dma_arena dma_phys_pages;
+struct dma_arena *dev_to_dma_arena(struct device *d)
+{
+ struct pci_device *pdev;
+
+ if (!d)
+ return &dma_phys_pages;
+ pdev = container_of(d, struct pci_device, linux_dev);
+ if (!pdev->proc_owner)
+ return &dma_phys_pages;
+ if (!pdev->proc_owner->user_pages) {
+ warn("Proc %d owns a device, but has no user_pages!",
+ pdev->proc_owner->pid);
+ return &dma_phys_pages;
+ }
+ return pdev->proc_owner->user_pages;
+}
+
static void *dma_phys_a(struct arena *a, size_t amt, int flags)
{
return (void*)PADDR(arena_alloc(a, amt, flags));
@@ -147,7 +164,7 @@
struct dma_arena *source;
};
-struct dma_pool *dma_pool_create(const char *name, void *dev,
+struct dma_pool *dma_pool_create(const char *name, struct device *dev,
size_t size, size_t align, size_t boundary)
{
struct dma_pool *dp;
@@ -164,8 +181,7 @@
align = size;
}
dp = kzmalloc(sizeof(struct dma_pool), MEM_WAIT);
- /* TODO: this will be device specific. Assuming the default. */
- dp->source = &dma_phys_pages;
+ dp->source = dev_to_dma_arena(dev);
/* We're sourcing directly from the dma_arena's arena. */
__kmem_cache_create(&dp->kc, name, size, align, KMC_NOTOUCH,
&dp->source->arena, NULL, NULL, NULL);
