diff options
Diffstat (limited to 'lib/scatterlist.c')
| -rw-r--r-- | lib/scatterlist.c | 36 |
1 files changed, 23 insertions, 13 deletions
diff --git a/lib/scatterlist.c b/lib/scatterlist.c index eacb82468437..c2cf2c311b7d 100644 --- a/lib/scatterlist.c +++ b/lib/scatterlist.c @@ -179,7 +179,8 @@ static void sg_kfree(struct scatterlist *sg, unsigned int nents) * __sg_free_table - Free a previously mapped sg table * @table: The sg table header to use * @max_ents: The maximum number of entries per single scatterlist - * @skip_first_chunk: don't free the (preallocated) first scatterlist chunk + * @nents_first_chunk: Number of entries int the (preallocated) first + * scatterlist chunk, 0 means no such preallocated first chunk * @free_fn: Free function * * Description: @@ -189,9 +190,10 @@ static void sg_kfree(struct scatterlist *sg, unsigned int nents) * **/ void __sg_free_table(struct sg_table *table, unsigned int max_ents, - bool skip_first_chunk, sg_free_fn *free_fn) + unsigned int nents_first_chunk, sg_free_fn *free_fn) { struct scatterlist *sgl, *next; + unsigned curr_max_ents = nents_first_chunk ?: max_ents; if (unlikely(!table->sgl)) return; @@ -207,9 +209,9 @@ void __sg_free_table(struct sg_table *table, unsigned int max_ents, * sg_size is then one less than alloc size, since the last * element is the chain pointer. */ - if (alloc_size > max_ents) { - next = sg_chain_ptr(&sgl[max_ents - 1]); - alloc_size = max_ents; + if (alloc_size > curr_max_ents) { + next = sg_chain_ptr(&sgl[curr_max_ents - 1]); + alloc_size = curr_max_ents; sg_size = alloc_size - 1; } else { sg_size = alloc_size; @@ -217,11 +219,12 @@ void __sg_free_table(struct sg_table *table, unsigned int max_ents, } table->orig_nents -= sg_size; - if (skip_first_chunk) - skip_first_chunk = false; + if (nents_first_chunk) + nents_first_chunk = 0; else free_fn(sgl, alloc_size); sgl = next; + curr_max_ents = max_ents; } table->sgl = NULL; @@ -244,6 +247,8 @@ EXPORT_SYMBOL(sg_free_table); * @table: The sg table header to use * @nents: Number of entries in sg list * @max_ents: The maximum number of entries the allocator returns per call + * @nents_first_chunk: Number of entries int the (preallocated) first + * scatterlist chunk, 0 means no such preallocated chunk provided by user * @gfp_mask: GFP allocation mask * @alloc_fn: Allocator to use * @@ -260,10 +265,13 @@ EXPORT_SYMBOL(sg_free_table); **/ int __sg_alloc_table(struct sg_table *table, unsigned int nents, unsigned int max_ents, struct scatterlist *first_chunk, - gfp_t gfp_mask, sg_alloc_fn *alloc_fn) + unsigned int nents_first_chunk, gfp_t gfp_mask, + sg_alloc_fn *alloc_fn) { struct scatterlist *sg, *prv; unsigned int left; + unsigned curr_max_ents = nents_first_chunk ?: max_ents; + unsigned prv_max_ents; memset(table, 0, sizeof(*table)); @@ -279,8 +287,8 @@ int __sg_alloc_table(struct sg_table *table, unsigned int nents, do { unsigned int sg_size, alloc_size = left; - if (alloc_size > max_ents) { - alloc_size = max_ents; + if (alloc_size > curr_max_ents) { + alloc_size = curr_max_ents; sg_size = alloc_size - 1; } else sg_size = alloc_size; @@ -314,7 +322,7 @@ int __sg_alloc_table(struct sg_table *table, unsigned int nents, * If this is not the first mapping, chain previous part. */ if (prv) - sg_chain(prv, max_ents, sg); + sg_chain(prv, prv_max_ents, sg); else table->sgl = sg; @@ -325,6 +333,8 @@ int __sg_alloc_table(struct sg_table *table, unsigned int nents, sg_mark_end(&sg[sg_size - 1]); prv = sg; + prv_max_ents = curr_max_ents; + curr_max_ents = max_ents; } while (left); return 0; @@ -347,9 +357,9 @@ int sg_alloc_table(struct sg_table *table, unsigned int nents, gfp_t gfp_mask) int ret; ret = __sg_alloc_table(table, nents, SG_MAX_SINGLE_ALLOC, - NULL, gfp_mask, sg_kmalloc); + NULL, 0, gfp_mask, sg_kmalloc); if (unlikely(ret)) - __sg_free_table(table, SG_MAX_SINGLE_ALLOC, false, sg_kfree); + __sg_free_table(table, SG_MAX_SINGLE_ALLOC, 0, sg_kfree); return ret; } |