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-rw-r--r--lib/iommu-common.c267
1 files changed, 0 insertions, 267 deletions
diff --git a/lib/iommu-common.c b/lib/iommu-common.c
deleted file mode 100644
index 55b00de106b5..000000000000
--- a/lib/iommu-common.c
+++ /dev/null
@@ -1,267 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-/*
- * IOMMU mmap management and range allocation functions.
- * Based almost entirely upon the powerpc iommu allocator.
- */
-
-#include <linux/export.h>
-#include <linux/bitmap.h>
-#include <linux/bug.h>
-#include <linux/iommu-helper.h>
-#include <linux/iommu-common.h>
-#include <linux/dma-mapping.h>
-#include <linux/hash.h>
-
-static unsigned long iommu_large_alloc = 15;
-
-static DEFINE_PER_CPU(unsigned int, iommu_hash_common);
-
-static inline bool need_flush(struct iommu_map_table *iommu)
-{
- return ((iommu->flags & IOMMU_NEED_FLUSH) != 0);
-}
-
-static inline void set_flush(struct iommu_map_table *iommu)
-{
- iommu->flags |= IOMMU_NEED_FLUSH;
-}
-
-static inline void clear_flush(struct iommu_map_table *iommu)
-{
- iommu->flags &= ~IOMMU_NEED_FLUSH;
-}
-
-static void setup_iommu_pool_hash(void)
-{
- unsigned int i;
- static bool do_once;
-
- if (do_once)
- return;
- do_once = true;
- for_each_possible_cpu(i)
- per_cpu(iommu_hash_common, i) = hash_32(i, IOMMU_POOL_HASHBITS);
-}
-
-/*
- * Initialize iommu_pool entries for the iommu_map_table. `num_entries'
- * is the number of table entries. If `large_pool' is set to true,
- * the top 1/4 of the table will be set aside for pool allocations
- * of more than iommu_large_alloc pages.
- */
-void iommu_tbl_pool_init(struct iommu_map_table *iommu,
- unsigned long num_entries,
- u32 table_shift,
- void (*lazy_flush)(struct iommu_map_table *),
- bool large_pool, u32 npools,
- bool skip_span_boundary_check)
-{
- unsigned int start, i;
- struct iommu_pool *p = &(iommu->large_pool);
-
- setup_iommu_pool_hash();
- if (npools == 0)
- iommu->nr_pools = IOMMU_NR_POOLS;
- else
- iommu->nr_pools = npools;
- BUG_ON(npools > IOMMU_NR_POOLS);
-
- iommu->table_shift = table_shift;
- iommu->lazy_flush = lazy_flush;
- start = 0;
- if (skip_span_boundary_check)
- iommu->flags |= IOMMU_NO_SPAN_BOUND;
- if (large_pool)
- iommu->flags |= IOMMU_HAS_LARGE_POOL;
-
- if (!large_pool)
- iommu->poolsize = num_entries/iommu->nr_pools;
- else
- iommu->poolsize = (num_entries * 3 / 4)/iommu->nr_pools;
- for (i = 0; i < iommu->nr_pools; i++) {
- spin_lock_init(&(iommu->pools[i].lock));
- iommu->pools[i].start = start;
- iommu->pools[i].hint = start;
- start += iommu->poolsize; /* start for next pool */
- iommu->pools[i].end = start - 1;
- }
- if (!large_pool)
- return;
- /* initialize large_pool */
- spin_lock_init(&(p->lock));
- p->start = start;
- p->hint = p->start;
- p->end = num_entries;
-}
-EXPORT_SYMBOL(iommu_tbl_pool_init);
-
-unsigned long iommu_tbl_range_alloc(struct device *dev,
- struct iommu_map_table *iommu,
- unsigned long npages,
- unsigned long *handle,
- unsigned long mask,
- unsigned int align_order)
-{
- unsigned int pool_hash = __this_cpu_read(iommu_hash_common);
- unsigned long n, end, start, limit, boundary_size;
- struct iommu_pool *pool;
- int pass = 0;
- unsigned int pool_nr;
- unsigned int npools = iommu->nr_pools;
- unsigned long flags;
- bool large_pool = ((iommu->flags & IOMMU_HAS_LARGE_POOL) != 0);
- bool largealloc = (large_pool && npages > iommu_large_alloc);
- unsigned long shift;
- unsigned long align_mask = 0;
-
- if (align_order > 0)
- align_mask = ~0ul >> (BITS_PER_LONG - align_order);
-
- /* Sanity check */
- if (unlikely(npages == 0)) {
- WARN_ON_ONCE(1);
- return IOMMU_ERROR_CODE;
- }
-
- if (largealloc) {
- pool = &(iommu->large_pool);
- pool_nr = 0; /* to keep compiler happy */
- } else {
- /* pick out pool_nr */
- pool_nr = pool_hash & (npools - 1);
- pool = &(iommu->pools[pool_nr]);
- }
- spin_lock_irqsave(&pool->lock, flags);
-
- again:
- if (pass == 0 && handle && *handle &&
- (*handle >= pool->start) && (*handle < pool->end))
- start = *handle;
- else
- start = pool->hint;
-
- limit = pool->end;
-
- /* The case below can happen if we have a small segment appended
- * to a large, or when the previous alloc was at the very end of
- * the available space. If so, go back to the beginning. If a
- * flush is needed, it will get done based on the return value
- * from iommu_area_alloc() below.
- */
- if (start >= limit)
- start = pool->start;
- shift = iommu->table_map_base >> iommu->table_shift;
- if (limit + shift > mask) {
- limit = mask - shift + 1;
- /* If we're constrained on address range, first try
- * at the masked hint to avoid O(n) search complexity,
- * but on second pass, start at 0 in pool 0.
- */
- if ((start & mask) >= limit || pass > 0) {
- spin_unlock(&(pool->lock));
- pool = &(iommu->pools[0]);
- spin_lock(&(pool->lock));
- start = pool->start;
- } else {
- start &= mask;
- }
- }
-
- if (dev)
- boundary_size = ALIGN(dma_get_seg_boundary(dev) + 1,
- 1 << iommu->table_shift);
- else
- boundary_size = ALIGN(1ULL << 32, 1 << iommu->table_shift);
-
- boundary_size = boundary_size >> iommu->table_shift;
- /*
- * if the skip_span_boundary_check had been set during init, we set
- * things up so that iommu_is_span_boundary() merely checks if the
- * (index + npages) < num_tsb_entries
- */
- if ((iommu->flags & IOMMU_NO_SPAN_BOUND) != 0) {
- shift = 0;
- boundary_size = iommu->poolsize * iommu->nr_pools;
- }
- n = iommu_area_alloc(iommu->map, limit, start, npages, shift,
- boundary_size, align_mask);
- if (n == -1) {
- if (likely(pass == 0)) {
- /* First failure, rescan from the beginning. */
- pool->hint = pool->start;
- set_flush(iommu);
- pass++;
- goto again;
- } else if (!largealloc && pass <= iommu->nr_pools) {
- spin_unlock(&(pool->lock));
- pool_nr = (pool_nr + 1) & (iommu->nr_pools - 1);
- pool = &(iommu->pools[pool_nr]);
- spin_lock(&(pool->lock));
- pool->hint = pool->start;
- set_flush(iommu);
- pass++;
- goto again;
- } else {
- /* give up */
- n = IOMMU_ERROR_CODE;
- goto bail;
- }
- }
- if (iommu->lazy_flush &&
- (n < pool->hint || need_flush(iommu))) {
- clear_flush(iommu);
- iommu->lazy_flush(iommu);
- }
-
- end = n + npages;
- pool->hint = end;
-
- /* Update handle for SG allocations */
- if (handle)
- *handle = end;
-bail:
- spin_unlock_irqrestore(&(pool->lock), flags);
-
- return n;
-}
-EXPORT_SYMBOL(iommu_tbl_range_alloc);
-
-static struct iommu_pool *get_pool(struct iommu_map_table *tbl,
- unsigned long entry)
-{
- struct iommu_pool *p;
- unsigned long largepool_start = tbl->large_pool.start;
- bool large_pool = ((tbl->flags & IOMMU_HAS_LARGE_POOL) != 0);
-
- /* The large pool is the last pool at the top of the table */
- if (large_pool && entry >= largepool_start) {
- p = &tbl->large_pool;
- } else {
- unsigned int pool_nr = entry / tbl->poolsize;
-
- BUG_ON(pool_nr >= tbl->nr_pools);
- p = &tbl->pools[pool_nr];
- }
- return p;
-}
-
-/* Caller supplies the index of the entry into the iommu map table
- * itself when the mapping from dma_addr to the entry is not the
- * default addr->entry mapping below.
- */
-void iommu_tbl_range_free(struct iommu_map_table *iommu, u64 dma_addr,
- unsigned long npages, unsigned long entry)
-{
- struct iommu_pool *pool;
- unsigned long flags;
- unsigned long shift = iommu->table_shift;
-
- if (entry == IOMMU_ERROR_CODE) /* use default addr->entry mapping */
- entry = (dma_addr - iommu->table_map_base) >> shift;
- pool = get_pool(iommu, entry);
-
- spin_lock_irqsave(&(pool->lock), flags);
- bitmap_clear(iommu->map, entry, npages);
- spin_unlock_irqrestore(&(pool->lock), flags);
-}
-EXPORT_SYMBOL(iommu_tbl_range_free);