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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);