Merge branch 'for-next/iommu/iova' into for-next/iommu/core

IOVA allocator updates for 5.11, including removal of unused symbols and
functions as well as some optimisations to improve allocation behaviour
in the face of fragmentation.

* for-next/iommu/iova:
  iommu: Stop exporting free_iova_mem()
  iommu: Stop exporting alloc_iova_mem()
  iommu: Delete split_and_remove_iova()
  iommu: avoid taking iova_rbtree_lock twice
  iommu/iova: Free global iova rcache on iova alloc failure
  iommu/iova: Retry from last rb tree node if iova search fails
This commit is contained in:
Will Deacon 2020-12-08 15:01:27 +00:00
commit 1ab2bf5831
2 changed files with 46 additions and 73 deletions

View file

@ -25,6 +25,7 @@ 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);
static void fq_flush_timeout(struct timer_list *t);
static void free_global_cached_iovas(struct iova_domain *iovad);
void
init_iova_domain(struct iova_domain *iovad, unsigned long granule,
@ -184,8 +185,9 @@ static int __alloc_and_insert_iova_range(struct iova_domain *iovad,
struct rb_node *curr, *prev;
struct iova *curr_iova;
unsigned long flags;
unsigned long new_pfn;
unsigned long new_pfn, retry_pfn;
unsigned long align_mask = ~0UL;
unsigned long high_pfn = limit_pfn, low_pfn = iovad->start_pfn;
if (size_aligned)
align_mask <<= fls_long(size - 1);
@ -198,15 +200,25 @@ static int __alloc_and_insert_iova_range(struct iova_domain *iovad,
curr = __get_cached_rbnode(iovad, limit_pfn);
curr_iova = rb_entry(curr, struct iova, node);
retry_pfn = curr_iova->pfn_hi + 1;
retry:
do {
limit_pfn = min(limit_pfn, curr_iova->pfn_lo);
new_pfn = (limit_pfn - size) & align_mask;
high_pfn = min(high_pfn, curr_iova->pfn_lo);
new_pfn = (high_pfn - size) & align_mask;
prev = curr;
curr = rb_prev(curr);
curr_iova = rb_entry(curr, struct iova, node);
} while (curr && new_pfn <= curr_iova->pfn_hi);
} while (curr && new_pfn <= curr_iova->pfn_hi && new_pfn >= low_pfn);
if (limit_pfn < size || new_pfn < iovad->start_pfn) {
if (high_pfn < size || new_pfn < low_pfn) {
if (low_pfn == iovad->start_pfn && retry_pfn < limit_pfn) {
high_pfn = limit_pfn;
low_pfn = retry_pfn;
curr = &iovad->anchor.node;
curr_iova = rb_entry(curr, struct iova, node);
goto retry;
}
iovad->max32_alloc_size = size;
goto iova32_full;
}
@ -231,18 +243,16 @@ static struct kmem_cache *iova_cache;
static unsigned int iova_cache_users;
static DEFINE_MUTEX(iova_cache_mutex);
struct iova *alloc_iova_mem(void)
static struct iova *alloc_iova_mem(void)
{
return kmem_cache_zalloc(iova_cache, GFP_ATOMIC | __GFP_NOWARN);
}
EXPORT_SYMBOL(alloc_iova_mem);
void free_iova_mem(struct iova *iova)
static void free_iova_mem(struct iova *iova)
{
if (iova->pfn_lo != IOVA_ANCHOR)
kmem_cache_free(iova_cache, iova);
}
EXPORT_SYMBOL(free_iova_mem);
int iova_cache_get(void)
{
@ -390,10 +400,14 @@ EXPORT_SYMBOL_GPL(__free_iova);
void
free_iova(struct iova_domain *iovad, unsigned long pfn)
{
struct iova *iova = find_iova(iovad, pfn);
unsigned long flags;
struct iova *iova;
spin_lock_irqsave(&iovad->iova_rbtree_lock, flags);
iova = private_find_iova(iovad, pfn);
if (iova)
__free_iova(iovad, iova);
private_free_iova(iovad, iova);
spin_unlock_irqrestore(&iovad->iova_rbtree_lock, flags);
}
EXPORT_SYMBOL_GPL(free_iova);
@ -431,6 +445,7 @@ alloc_iova_fast(struct iova_domain *iovad, unsigned long size,
flush_rcache = false;
for_each_online_cpu(cpu)
free_cpu_cached_iovas(cpu, iovad);
free_global_cached_iovas(iovad);
goto retry;
}
@ -725,47 +740,6 @@ copy_reserved_iova(struct iova_domain *from, struct iova_domain *to)
}
EXPORT_SYMBOL_GPL(copy_reserved_iova);
struct iova *
split_and_remove_iova(struct iova_domain *iovad, struct iova *iova,
unsigned long pfn_lo, unsigned long pfn_hi)
{
unsigned long flags;
struct iova *prev = NULL, *next = NULL;
spin_lock_irqsave(&iovad->iova_rbtree_lock, flags);
if (iova->pfn_lo < pfn_lo) {
prev = alloc_and_init_iova(iova->pfn_lo, pfn_lo - 1);
if (prev == NULL)
goto error;
}
if (iova->pfn_hi > pfn_hi) {
next = alloc_and_init_iova(pfn_hi + 1, iova->pfn_hi);
if (next == NULL)
goto error;
}
__cached_rbnode_delete_update(iovad, iova);
rb_erase(&iova->node, &iovad->rbroot);
if (prev) {
iova_insert_rbtree(&iovad->rbroot, prev, NULL);
iova->pfn_lo = pfn_lo;
}
if (next) {
iova_insert_rbtree(&iovad->rbroot, next, NULL);
iova->pfn_hi = pfn_hi;
}
spin_unlock_irqrestore(&iovad->iova_rbtree_lock, flags);
return iova;
error:
spin_unlock_irqrestore(&iovad->iova_rbtree_lock, flags);
if (prev)
free_iova_mem(prev);
return NULL;
}
/*
* Magazine caches for IOVA ranges. For an introduction to magazines,
* see the USENIX 2001 paper "Magazines and Vmem: Extending the Slab
@ -1046,5 +1020,25 @@ void free_cpu_cached_iovas(unsigned int cpu, struct iova_domain *iovad)
}
}
/*
* free all the IOVA ranges of global cache
*/
static void free_global_cached_iovas(struct iova_domain *iovad)
{
struct iova_rcache *rcache;
unsigned long flags;
int i, j;
for (i = 0; i < IOVA_RANGE_CACHE_MAX_SIZE; ++i) {
rcache = &iovad->rcaches[i];
spin_lock_irqsave(&rcache->lock, flags);
for (j = 0; j < rcache->depot_size; ++j) {
iova_magazine_free_pfns(rcache->depot[j], iovad);
iova_magazine_free(rcache->depot[j]);
}
rcache->depot_size = 0;
spin_unlock_irqrestore(&rcache->lock, flags);
}
}
MODULE_AUTHOR("Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>");
MODULE_LICENSE("GPL");

View file

@ -136,8 +136,6 @@ static inline unsigned long iova_pfn(struct iova_domain *iovad, dma_addr_t iova)
int iova_cache_get(void);
void iova_cache_put(void);
struct iova *alloc_iova_mem(void);
void free_iova_mem(struct iova *iova);
void free_iova(struct iova_domain *iovad, unsigned long pfn);
void __free_iova(struct iova_domain *iovad, struct iova *iova);
struct iova *alloc_iova(struct iova_domain *iovad, unsigned long size,
@ -160,8 +158,6 @@ int init_iova_flush_queue(struct iova_domain *iovad,
iova_flush_cb flush_cb, iova_entry_dtor entry_dtor);
struct iova *find_iova(struct iova_domain *iovad, unsigned long pfn);
void put_iova_domain(struct iova_domain *iovad);
struct iova *split_and_remove_iova(struct iova_domain *iovad,
struct iova *iova, unsigned long pfn_lo, unsigned long pfn_hi);
void free_cpu_cached_iovas(unsigned int cpu, struct iova_domain *iovad);
#else
static inline int iova_cache_get(void)
@ -173,15 +169,6 @@ static inline void iova_cache_put(void)
{
}
static inline struct iova *alloc_iova_mem(void)
{
return NULL;
}
static inline void free_iova_mem(struct iova *iova)
{
}
static inline void free_iova(struct iova_domain *iovad, unsigned long pfn)
{
}
@ -258,14 +245,6 @@ static inline void put_iova_domain(struct iova_domain *iovad)
{
}
static inline struct iova *split_and_remove_iova(struct iova_domain *iovad,
struct iova *iova,
unsigned long pfn_lo,
unsigned long pfn_hi)
{
return NULL;
}
static inline void free_cpu_cached_iovas(unsigned int cpu,
struct iova_domain *iovad)
{