diff options
Diffstat (limited to 'lib/iommu-common.c')
-rw-r--r-- | lib/iommu-common.c | 267 |
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); |