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Consolidate all of the bounce tests into the BUS_DMA_COULD_BOUNCE flag.

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Allocate the bounce zone at either tag creation or map creation to help
avoid null-pointer derefs later on.  Track total pages per zone so that
each zone can get a minimum allocation at tag creation time instead of
being defeated by mis-behaving tags that suck up the max amount.
This commit is contained in:
scottl 2004-11-21 04:15:26 +00:00
parent 0b30660485
commit 3018b80090
1 changed files with 45 additions and 29 deletions
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74
sys/amd64/amd64/busdma_machdep.c
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@ -87,6 +87,7 @@ int busdma_swi_pending;
struct bounce_zone {
STAILQ_ENTRY(bounce_zone) links;
STAILQ_HEAD(bp_list, bounce_page) bounce_page_list;
int total_bpages;
int free_bpages;
int reserved_bpages;
int active_bpages;
@ -128,7 +129,7 @@ static STAILQ_HEAD(, bus_dmamap) bounce_map_callbacklist;
static struct bus_dmamap nobounce_dmamap;
static void init_bounce_pages(void *dummy);
static struct bounce_zone * alloc_bounce_zone(bus_dma_tag_t dmat);
static int alloc_bounce_zone(bus_dma_tag_t dmat);
static int alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages);
static int reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map,
int commit);
@ -200,7 +201,8 @@ dflt_lock(void *arg, bus_dma_lock_op_t op)
panic("driver error: busdma dflt_lock called");
}
#define BUS_DMA_MIN_ALLOC_COMP BUS_DMA_BUS4
#define BUS_DMA_COULD_BOUNCE BUS_DMA_BUS3
#define BUS_DMA_MIN_ALLOC_COMP BUS_DMA_BUS4
/*
* Allocate a device specific dma_tag.
*/
@ -274,11 +276,21 @@ bus_dma_tag_create(bus_dma_tag_t parent, bus_size_t alignment,
if (newtag->parent != NULL)
atomic_add_int(&parent->ref_count, 1);
}
if (newtag->lowaddr < ptoa((vm_paddr_t)Maxmem) &&
if (newtag->lowaddr < ptoa((vm_paddr_t)Maxmem)
|| newtag->alignment > 1 || newtag->boundary > 0)
newtag->flags |= BUS_DMA_COULD_BOUNCE;
if (((newtag->flags & BUS_DMA_COULD_BOUNCE) != 0) &&
(flags & BUS_DMA_ALLOCNOW) != 0) {
struct bounce_zone *bz;
/* Must bounce */
if ((error = alloc_bounce_zone(newtag)) != 0)
return (error);
bz = newtag->bounce_zone;
if (lowaddr > bounce_lowaddr) {
/*
* Go through the pool and kill any pages
@ -287,10 +299,10 @@ bus_dma_tag_create(bus_dma_tag_t parent, bus_size_t alignment,
panic("bus_dma_tag_create: page reallocation "
"not implemented");
}
if (ptoa(total_bpages) < maxsize) {
if (ptoa(bz->total_bpages) < maxsize) {
int pages;
pages = atop(maxsize) - total_bpages;
pages = atop(maxsize) - bz->total_bpages;
/* Add pages to our bounce pool */
if (alloc_bounce_pages(newtag, pages) < pages)
@ -378,12 +390,16 @@ bus_dmamap_create(bus_dma_tag_t dmat, int flags, bus_dmamap_t *mapp)
* exclusion region, a data alignment that is stricter than 1, and/or
* an active address boundary.
*/
if (dmat->lowaddr < ptoa((vm_paddr_t)Maxmem)
|| dmat->alignment > 1 || dmat->boundary > 0) {
if (dmat->flags & BUS_DMA_COULD_BOUNCE) {
/* Must bounce */
int maxpages;
if (dmat->bounce_zone == NULL) {
if ((error = alloc_bounce_zone(dmat)) != 0)
return (error);
}
*mapp = (bus_dmamap_t)malloc(sizeof(**mapp), M_DEVBUF,
M_NOWAIT | M_ZERO);
if (*mapp == NULL) {
@ -564,8 +580,7 @@ _bus_dmamap_load_buffer(bus_dma_tag_t dmat,
map = &nobounce_dmamap;
if ((map != &nobounce_dmamap && map->pagesneeded == 0)
&& (dmat->lowaddr < ptoa((vm_paddr_t)Maxmem)
|| dmat->boundary > 0 || dmat->alignment > 1)) {
&& ((dmat->flags & BUS_DMA_COULD_BOUNCE) != 0)) {
vm_offset_t vendaddr;
CTR4(KTR_BUSDMA, "lowaddr= %d Maxmem= %d, boundary= %d, "
@ -898,14 +913,24 @@ busdma_sysctl_tree_top(struct bounce_zone *bz)
return (bz->sysctl_tree_top);
}
static struct bounce_zone *
static int
alloc_bounce_zone(bus_dma_tag_t dmat)
{
struct bounce_zone *bz;
/* Check to see if we already have a suitable zone */
STAILQ_FOREACH(bz, &bounce_zone_list, links) {
if ((dmat->alignment <= bz->alignment)
&& (dmat->boundary <= bz->boundary)
&& (dmat->lowaddr >= bz->lowaddr)) {
dmat->bounce_zone = bz;
return (0);
}
}
if ((bz = (struct bounce_zone *)malloc(sizeof(*bz), M_DEVBUF,
M_NOWAIT | M_ZERO)) == NULL)
return (NULL);
return (ENOMEM);
STAILQ_INIT(&bz->bounce_page_list);
bz->free_bpages = 0;
@ -918,6 +943,7 @@ alloc_bounce_zone(bus_dma_tag_t dmat)
busdma_zonecount++;
snprintf(bz->lowaddrid, 18, "%#jx", (uintmax_t)bz->lowaddr);
STAILQ_INSERT_TAIL(&bounce_zone_list, bz, links);
dmat->bounce_zone = bz;
sysctl_ctx_init(&bz->sysctl_tree);
bz->sysctl_tree_top = SYSCTL_ADD_NODE(&bz->sysctl_tree,
@ -925,9 +951,13 @@ alloc_bounce_zone(bus_dma_tag_t dmat)
CTLFLAG_RD, 0, "");
if (bz->sysctl_tree_top == NULL) {
sysctl_ctx_free(&bz->sysctl_tree);
return (bz);
return (0); /* XXX error code? */
}
SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
"total_bpages", CTLFLAG_RD, &bz->total_bpages, 0,
"Totoal bounce pages");
SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
"free_bpages", CTLFLAG_RD, &bz->free_bpages, 0,
@ -958,7 +988,7 @@ alloc_bounce_zone(bus_dma_tag_t dmat)
SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
"boundary", CTLFLAG_RD, &bz->boundary, 0, "");
return (bz);
return (0);
}
static int
@ -968,21 +998,6 @@ alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages)
int count;
bz = dmat->bounce_zone;
if (bz == NULL) {
STAILQ_FOREACH(bz, &bounce_zone_list, links) {
if ((dmat->alignment <= bz->alignment)
&& (dmat->boundary <= bz->boundary)
&& (dmat->lowaddr >= bz->lowaddr))
break;
}
if (bz == NULL) {
if ((bz = alloc_bounce_zone(dmat)) == NULL)
return (ENOMEM);
}
dmat->bounce_zone = bz;
}
count = 0;
while (numpages > 0) {
struct bounce_page *bpage;
@ -1005,6 +1020,7 @@ alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages)
mtx_lock(&bounce_lock);
STAILQ_INSERT_TAIL(&bz->bounce_page_list, bpage, links);
total_bpages++;
bz->total_bpages++;
bz->free_bpages++;
mtx_unlock(&bounce_lock);
count++;