iommu/iova: Implement Flush-Queue ring buffer

Add a function to add entries to the Flush-Queue ring
buffer. If the buffer is full, call the flush-callback and
free the entries.

Signed-off-by: Joerg Roedel <jroedel@suse.de>
This commit is contained in:
Joerg Roedel 2017-08-10 15:49:44 +02:00
parent 42f87e71c3
commit 1928210107
2 changed files with 89 additions and 0 deletions

View File

@ -32,6 +32,7 @@ static unsigned long iova_rcache_get(struct iova_domain *iovad,
unsigned long limit_pfn);
static void init_iova_rcaches(struct iova_domain *iovad);
static void free_iova_rcaches(struct iova_domain *iovad);
static void fq_destroy_all_entries(struct iova_domain *iovad);
void
init_iova_domain(struct iova_domain *iovad, unsigned long granule,
@ -61,6 +62,7 @@ static void free_iova_flush_queue(struct iova_domain *iovad)
if (!iovad->fq)
return;
fq_destroy_all_entries(iovad);
free_percpu(iovad->fq);
iovad->fq = NULL;
@ -461,6 +463,84 @@ free_iova_fast(struct iova_domain *iovad, unsigned long pfn, unsigned long size)
}
EXPORT_SYMBOL_GPL(free_iova_fast);
#define fq_ring_for_each(i, fq) \
for ((i) = (fq)->head; (i) != (fq)->tail; (i) = ((i) + 1) % IOVA_FQ_SIZE)
static inline bool fq_full(struct iova_fq *fq)
{
return (((fq->tail + 1) % IOVA_FQ_SIZE) == fq->head);
}
static inline unsigned fq_ring_add(struct iova_fq *fq)
{
unsigned idx = fq->tail;
fq->tail = (idx + 1) % IOVA_FQ_SIZE;
return idx;
}
static void fq_ring_free(struct iova_domain *iovad, struct iova_fq *fq)
{
unsigned idx;
fq_ring_for_each(idx, fq) {
if (iovad->entry_dtor)
iovad->entry_dtor(fq->entries[idx].data);
free_iova_fast(iovad,
fq->entries[idx].iova_pfn,
fq->entries[idx].pages);
}
fq->head = 0;
fq->tail = 0;
}
static void fq_destroy_all_entries(struct iova_domain *iovad)
{
int cpu;
/*
* This code runs when the iova_domain is being detroyed, so don't
* bother to free iovas, just call the entry_dtor on all remaining
* entries.
*/
if (!iovad->entry_dtor)
return;
for_each_possible_cpu(cpu) {
struct iova_fq *fq = per_cpu_ptr(iovad->fq, cpu);
int idx;
fq_ring_for_each(idx, fq)
iovad->entry_dtor(fq->entries[idx].data);
}
}
void queue_iova(struct iova_domain *iovad,
unsigned long pfn, unsigned long pages,
unsigned long data)
{
struct iova_fq *fq = get_cpu_ptr(iovad->fq);
unsigned idx;
if (fq_full(fq)) {
iovad->flush_cb(iovad);
fq_ring_free(iovad, fq);
}
idx = fq_ring_add(fq);
fq->entries[idx].iova_pfn = pfn;
fq->entries[idx].pages = pages;
fq->entries[idx].data = data;
put_cpu_ptr(iovad->fq);
}
EXPORT_SYMBOL_GPL(queue_iova);
/**
* put_iova_domain - destroys the iova doamin
* @iovad: - iova domain in question.

View File

@ -127,6 +127,9 @@ struct iova *alloc_iova(struct iova_domain *iovad, unsigned long size,
bool size_aligned);
void free_iova_fast(struct iova_domain *iovad, unsigned long pfn,
unsigned long size);
void queue_iova(struct iova_domain *iovad,
unsigned long pfn, unsigned long pages,
unsigned long data);
unsigned long alloc_iova_fast(struct iova_domain *iovad, unsigned long size,
unsigned long limit_pfn);
struct iova *reserve_iova(struct iova_domain *iovad, unsigned long pfn_lo,
@ -182,6 +185,12 @@ static inline void free_iova_fast(struct iova_domain *iovad,
{
}
static inline void queue_iova(struct iova_domain *iovad,
unsigned long pfn, unsigned long pages,
unsigned long data)
{
}
static inline unsigned long alloc_iova_fast(struct iova_domain *iovad,
unsigned long size,
unsigned long limit_pfn)