static struct kmem_cache *rbd_img_request_cache;
static struct kmem_cache *rbd_obj_request_cache;
-static struct bio_set *rbd_bio_clone;
-
static int rbd_major;
static DEFINE_IDA(rbd_dev_id_ida);
}
/*
- * bio helpers
- */
-
-static void bio_chain_put(struct bio *chain)
-{
- struct bio *tmp;
-
- while (chain) {
- tmp = chain;
- chain = chain->bi_next;
- bio_put(tmp);
- }
-}
-
-/*
- * zeros a bio chain, starting at specific offset
- */
-static void zero_bio_chain(struct bio *chain, int start_ofs)
-{
- struct bio_vec bv;
- struct bvec_iter iter;
- unsigned long flags;
- void *buf;
- int pos = 0;
-
- while (chain) {
- bio_for_each_segment(bv, chain, iter) {
- if (pos + bv.bv_len > start_ofs) {
- int remainder = max(start_ofs - pos, 0);
- buf = bvec_kmap_irq(&bv, &flags);
- memset(buf + remainder, 0,
- bv.bv_len - remainder);
- flush_dcache_page(bv.bv_page);
- bvec_kunmap_irq(buf, &flags);
- }
- pos += bv.bv_len;
- }
-
- chain = chain->bi_next;
- }
-}
-
-/*
* similar to zero_bio_chain(), zeros data defined by a page array,
* starting at the given byte offset from the start of the array and
* continuing up to the given end offset. The pages array is
}
/*
- * Clone a portion of a bio, starting at the given byte offset
- * and continuing for the number of bytes indicated.
- */
-static struct bio *bio_clone_range(struct bio *bio_src,
- unsigned int offset,
- unsigned int len,
- gfp_t gfpmask)
-{
- struct bio *bio;
-
- bio = bio_clone_fast(bio_src, gfpmask, rbd_bio_clone);
- if (!bio)
- return NULL; /* ENOMEM */
-
- bio_advance(bio, offset);
- bio->bi_iter.bi_size = len;
-
- return bio;
-}
-
-/*
- * Clone a portion of a bio chain, starting at the given byte offset
- * into the first bio in the source chain and continuing for the
- * number of bytes indicated. The result is another bio chain of
- * exactly the given length, or a null pointer on error.
- *
- * The bio_src and offset parameters are both in-out. On entry they
- * refer to the first source bio and the offset into that bio where
- * the start of data to be cloned is located.
- *
- * On return, bio_src is updated to refer to the bio in the source
- * chain that contains first un-cloned byte, and *offset will
- * contain the offset of that byte within that bio.
- */
-static struct bio *bio_chain_clone_range(struct bio **bio_src,
- unsigned int *offset,
- unsigned int len,
- gfp_t gfpmask)
-{
- struct bio *bi = *bio_src;
- unsigned int off = *offset;
- struct bio *chain = NULL;
- struct bio **end;
-
- /* Build up a chain of clone bios up to the limit */
-
- if (!bi || off >= bi->bi_iter.bi_size || !len)
- return NULL; /* Nothing to clone */
-
- end = &chain;
- while (len) {
- unsigned int bi_size;
- struct bio *bio;
-
- if (!bi) {
- rbd_warn(NULL, "bio_chain exhausted with %u left", len);
- goto out_err; /* EINVAL; ran out of bio's */
- }
- bi_size = min_t(unsigned int, bi->bi_iter.bi_size - off, len);
- bio = bio_clone_range(bi, off, bi_size, gfpmask);
- if (!bio)
- goto out_err; /* ENOMEM */
-
- *end = bio;
- end = &bio->bi_next;
-
- off += bi_size;
- if (off == bi->bi_iter.bi_size) {
- bi = bi->bi_next;
- off = 0;
- }
- len -= bi_size;
- }
- *bio_src = bi;
- *offset = off;
-
- return chain;
-out_err:
- bio_chain_put(chain);
-
- return NULL;
-}
-
-/*
* The default/initial value for all object request flags is 0. For
* each flag, once its value is set to 1 it is never reset to 0
* again.
if (!rbd_obj_request_cache)
goto out_err;
- rbd_assert(!rbd_bio_clone);
- rbd_bio_clone = bioset_create(BIO_POOL_SIZE, 0, 0);
- if (!rbd_bio_clone)
- goto out_err_clone;
-
return 0;
-out_err_clone:
- kmem_cache_destroy(rbd_obj_request_cache);
- rbd_obj_request_cache = NULL;
out_err:
kmem_cache_destroy(rbd_img_request_cache);
rbd_img_request_cache = NULL;
rbd_assert(rbd_img_request_cache);
kmem_cache_destroy(rbd_img_request_cache);
rbd_img_request_cache = NULL;
-
- rbd_assert(rbd_bio_clone);
- bioset_free(rbd_bio_clone);
- rbd_bio_clone = NULL;
}
static int __init rbd_init(void)