* issued.
*/
static int pblk_read_from_cache(struct pblk *pblk, struct bio *bio,
- sector_t lba, struct ppa_addr ppa,
- int bio_iter, bool advanced_bio)
+ sector_t lba, struct ppa_addr ppa)
{
#ifdef CONFIG_NVM_PBLK_DEBUG
/* Callers must ensure that the ppa points to a cache address */
BUG_ON(!pblk_addr_in_cache(ppa));
#endif
- return pblk_rb_copy_to_bio(&pblk->rwb, bio, lba, ppa,
- bio_iter, advanced_bio);
+ return pblk_rb_copy_to_bio(&pblk->rwb, bio, lba, ppa);
}
-static void pblk_read_ppalist_rq(struct pblk *pblk, struct nvm_rq *rqd,
+static int pblk_read_ppalist_rq(struct pblk *pblk, struct nvm_rq *rqd,
struct bio *bio, sector_t blba,
- unsigned long *read_bitmap)
+ bool *from_cache)
{
void *meta_list = rqd->meta_list;
- struct ppa_addr ppas[NVM_MAX_VLBA];
- int nr_secs = rqd->nr_ppas;
- bool advanced_bio = false;
- int i, j = 0;
+ int nr_secs, i;
- pblk_lookup_l2p_seq(pblk, ppas, blba, nr_secs);
+retry:
+ nr_secs = pblk_lookup_l2p_seq(pblk, rqd->ppa_list, blba, rqd->nr_ppas,
+ from_cache);
+
+ if (!*from_cache)
+ goto end;
for (i = 0; i < nr_secs; i++) {
- struct ppa_addr p = ppas[i];
struct pblk_sec_meta *meta = pblk_get_meta(pblk, meta_list, i);
sector_t lba = blba + i;
-retry:
- if (pblk_ppa_empty(p)) {
+ if (pblk_ppa_empty(rqd->ppa_list[i])) {
__le64 addr_empty = cpu_to_le64(ADDR_EMPTY);
- WARN_ON(test_and_set_bit(i, read_bitmap));
meta->lba = addr_empty;
-
- if (unlikely(!advanced_bio)) {
- bio_advance(bio, (i) * PBLK_EXPOSED_PAGE_SIZE);
- advanced_bio = true;
+ } else if (pblk_addr_in_cache(rqd->ppa_list[i])) {
+ /*
+ * Try to read from write buffer. The address is later
+ * checked on the write buffer to prevent retrieving
+ * overwritten data.
+ */
+ if (!pblk_read_from_cache(pblk, bio, lba,
+ rqd->ppa_list[i])) {
+ if (i == 0) {
+ /*
+ * We didn't call with bio_advance()
+ * yet, so we can just retry.
+ */
+ goto retry;
+ } else {
+ /*
+ * We already call bio_advance()
+ * so we cannot retry and we need
+ * to quit that function in order
+ * to allow caller to handle the bio
+ * splitting in the current sector
+ * position.
+ */
+ nr_secs = i;
+ goto end;
+ }
}
-
- goto next;
- }
-
- /* Try to read from write buffer. The address is later checked
- * on the write buffer to prevent retrieving overwritten data.
- */
- if (pblk_addr_in_cache(p)) {
- if (!pblk_read_from_cache(pblk, bio, lba, p, i,
- advanced_bio)) {
- pblk_lookup_l2p_seq(pblk, &p, lba, 1);
- goto retry;
- }
- WARN_ON(test_and_set_bit(i, read_bitmap));
meta->lba = cpu_to_le64(lba);
- advanced_bio = true;
#ifdef CONFIG_NVM_PBLK_DEBUG
atomic_long_inc(&pblk->cache_reads);
#endif
- } else {
- /* Read from media non-cached sectors */
- rqd->ppa_list[j++] = p;
}
-
-next:
- if (advanced_bio)
- bio_advance(bio, PBLK_EXPOSED_PAGE_SIZE);
+ bio_advance(bio, PBLK_EXPOSED_PAGE_SIZE);
}
+end:
if (pblk_io_aligned(pblk, nr_secs))
rqd->is_seq = 1;
#ifdef CONFIG_NVM_PBLK_DEBUG
atomic_long_add(nr_secs, &pblk->inflight_reads);
#endif
+
+ return nr_secs;
}
pblk_log_read_err(pblk, rqd);
pblk_read_check_seq(pblk, rqd, r_ctx->lba);
-
- if (int_bio)
- bio_put(int_bio);
+ bio_put(int_bio);
if (put_line)
pblk_rq_to_line_put(pblk, rqd);
__pblk_end_io_read(pblk, rqd, true);
}
-static void pblk_end_partial_read(struct nvm_rq *rqd)
-{
- struct pblk *pblk = rqd->private;
- struct pblk_g_ctx *r_ctx = nvm_rq_to_pdu(rqd);
- struct pblk_pr_ctx *pr_ctx = r_ctx->private;
- struct pblk_sec_meta *meta;
- struct bio *new_bio = rqd->bio;
- struct bio *bio = pr_ctx->orig_bio;
- void *meta_list = rqd->meta_list;
- unsigned long *read_bitmap = pr_ctx->bitmap;
- struct bvec_iter orig_iter = BVEC_ITER_ALL_INIT;
- struct bvec_iter new_iter = BVEC_ITER_ALL_INIT;
- int nr_secs = pr_ctx->orig_nr_secs;
- int nr_holes = nr_secs - bitmap_weight(read_bitmap, nr_secs);
- void *src_p, *dst_p;
- int bit, i;
-
- if (unlikely(nr_holes == 1)) {
- struct ppa_addr ppa;
-
- ppa = rqd->ppa_addr;
- rqd->ppa_list = pr_ctx->ppa_ptr;
- rqd->dma_ppa_list = pr_ctx->dma_ppa_list;
- rqd->ppa_list[0] = ppa;
- }
-
- for (i = 0; i < nr_secs; i++) {
- meta = pblk_get_meta(pblk, meta_list, i);
- pr_ctx->lba_list_media[i] = le64_to_cpu(meta->lba);
- meta->lba = cpu_to_le64(pr_ctx->lba_list_mem[i]);
- }
-
- /* Fill the holes in the original bio */
- i = 0;
- for (bit = 0; bit < nr_secs; bit++) {
- if (!test_bit(bit, read_bitmap)) {
- struct bio_vec dst_bv, src_bv;
- struct pblk_line *line;
-
- line = pblk_ppa_to_line(pblk, rqd->ppa_list[i]);
- kref_put(&line->ref, pblk_line_put);
-
- meta = pblk_get_meta(pblk, meta_list, bit);
- meta->lba = cpu_to_le64(pr_ctx->lba_list_media[i]);
-
- dst_bv = bio_iter_iovec(bio, orig_iter);
- src_bv = bio_iter_iovec(new_bio, new_iter);
-
- src_p = kmap_atomic(src_bv.bv_page);
- dst_p = kmap_atomic(dst_bv.bv_page);
-
- memcpy(dst_p + dst_bv.bv_offset,
- src_p + src_bv.bv_offset,
- PBLK_EXPOSED_PAGE_SIZE);
-
- kunmap_atomic(src_p);
- kunmap_atomic(dst_p);
-
- flush_dcache_page(dst_bv.bv_page);
- mempool_free(src_bv.bv_page, &pblk->page_bio_pool);
-
- bio_advance_iter(new_bio, &new_iter,
- PBLK_EXPOSED_PAGE_SIZE);
- i++;
- }
- bio_advance_iter(bio, &orig_iter, PBLK_EXPOSED_PAGE_SIZE);
- }
-
- bio_put(new_bio);
- kfree(pr_ctx);
-
- /* restore original request */
- rqd->bio = NULL;
- rqd->nr_ppas = nr_secs;
-
- pblk_end_user_read(bio, rqd->error);
- __pblk_end_io_read(pblk, rqd, false);
-}
-
-static int pblk_setup_partial_read(struct pblk *pblk, struct nvm_rq *rqd,
- unsigned int bio_init_idx,
- unsigned long *read_bitmap,
- int nr_holes)
-{
- void *meta_list = rqd->meta_list;
- struct pblk_g_ctx *r_ctx = nvm_rq_to_pdu(rqd);
- struct pblk_pr_ctx *pr_ctx;
- struct bio *new_bio, *bio = r_ctx->private;
- int nr_secs = rqd->nr_ppas;
- int i;
-
- new_bio = bio_alloc(GFP_KERNEL, nr_holes);
-
- if (pblk_bio_add_pages(pblk, new_bio, GFP_KERNEL, nr_holes))
- goto fail_bio_put;
-
- if (nr_holes != new_bio->bi_vcnt) {
- WARN_ONCE(1, "pblk: malformed bio\n");
- goto fail_free_pages;
- }
-
- pr_ctx = kzalloc(sizeof(struct pblk_pr_ctx), GFP_KERNEL);
- if (!pr_ctx)
- goto fail_free_pages;
-
- for (i = 0; i < nr_secs; i++) {
- struct pblk_sec_meta *meta = pblk_get_meta(pblk, meta_list, i);
-
- pr_ctx->lba_list_mem[i] = le64_to_cpu(meta->lba);
- }
-
- new_bio->bi_iter.bi_sector = 0; /* internal bio */
- bio_set_op_attrs(new_bio, REQ_OP_READ, 0);
-
- rqd->bio = new_bio;
- rqd->nr_ppas = nr_holes;
-
- pr_ctx->orig_bio = bio;
- bitmap_copy(pr_ctx->bitmap, read_bitmap, NVM_MAX_VLBA);
- pr_ctx->bio_init_idx = bio_init_idx;
- pr_ctx->orig_nr_secs = nr_secs;
- r_ctx->private = pr_ctx;
-
- if (unlikely(nr_holes == 1)) {
- pr_ctx->ppa_ptr = rqd->ppa_list;
- pr_ctx->dma_ppa_list = rqd->dma_ppa_list;
- rqd->ppa_addr = rqd->ppa_list[0];
- }
- return 0;
-
-fail_free_pages:
- pblk_bio_free_pages(pblk, new_bio, 0, new_bio->bi_vcnt);
-fail_bio_put:
- bio_put(new_bio);
-
- return -ENOMEM;
-}
-
-static int pblk_partial_read_bio(struct pblk *pblk, struct nvm_rq *rqd,
- unsigned int bio_init_idx,
- unsigned long *read_bitmap, int nr_secs)
-{
- int nr_holes;
- int ret;
-
- nr_holes = nr_secs - bitmap_weight(read_bitmap, nr_secs);
-
- if (pblk_setup_partial_read(pblk, rqd, bio_init_idx, read_bitmap,
- nr_holes))
- return NVM_IO_ERR;
-
- rqd->end_io = pblk_end_partial_read;
-
- ret = pblk_submit_io(pblk, rqd);
- if (ret) {
- bio_put(rqd->bio);
- pblk_err(pblk, "partial read IO submission failed\n");
- goto err;
- }
-
- return NVM_IO_OK;
-
-err:
- pblk_err(pblk, "failed to perform partial read\n");
-
- /* Free allocated pages in new bio */
- pblk_bio_free_pages(pblk, rqd->bio, 0, rqd->bio->bi_vcnt);
- return NVM_IO_ERR;
-}
-
static void pblk_read_rq(struct pblk *pblk, struct nvm_rq *rqd, struct bio *bio,
- sector_t lba, unsigned long *read_bitmap)
+ sector_t lba, bool *from_cache)
{
struct pblk_sec_meta *meta = pblk_get_meta(pblk, rqd->meta_list, 0);
struct ppa_addr ppa;
- pblk_lookup_l2p_seq(pblk, &ppa, lba, 1);
+ pblk_lookup_l2p_seq(pblk, &ppa, lba, 1, from_cache);
#ifdef CONFIG_NVM_PBLK_DEBUG
atomic_long_inc(&pblk->inflight_reads);
if (pblk_ppa_empty(ppa)) {
__le64 addr_empty = cpu_to_le64(ADDR_EMPTY);
- WARN_ON(test_and_set_bit(0, read_bitmap));
meta->lba = addr_empty;
return;
}
* write buffer to prevent retrieving overwritten data.
*/
if (pblk_addr_in_cache(ppa)) {
- if (!pblk_read_from_cache(pblk, bio, lba, ppa, 0, 1)) {
- pblk_lookup_l2p_seq(pblk, &ppa, lba, 1);
+ if (!pblk_read_from_cache(pblk, bio, lba, ppa)) {
+ pblk_lookup_l2p_seq(pblk, &ppa, lba, 1, from_cache);
goto retry;
}
- WARN_ON(test_and_set_bit(0, read_bitmap));
meta->lba = cpu_to_le64(lba);
#ifdef CONFIG_NVM_PBLK_DEBUG
struct request_queue *q = dev->q;
sector_t blba = pblk_get_lba(bio);
unsigned int nr_secs = pblk_get_secs(bio);
+ bool from_cache;
struct pblk_g_ctx *r_ctx;
struct nvm_rq *rqd;
- struct bio *int_bio;
- unsigned int bio_init_idx;
- DECLARE_BITMAP(read_bitmap, NVM_MAX_VLBA);
+ struct bio *int_bio, *split_bio;
generic_start_io_acct(q, REQ_OP_READ, bio_sectors(bio),
&pblk->disk->part0);
- bitmap_zero(read_bitmap, nr_secs);
-
rqd = pblk_alloc_rqd(pblk, PBLK_READ);
rqd->opcode = NVM_OP_PREAD;
r_ctx->start_time = jiffies;
r_ctx->lba = blba;
- /* Save the index for this bio's start. This is needed in case
- * we need to fill a partial read.
- */
- bio_init_idx = pblk_get_bi_idx(bio);
-
if (pblk_alloc_rqd_meta(pblk, rqd)) {
bio_io_error(bio);
pblk_free_rqd(pblk, rqd, PBLK_READ);
/* Clone read bio to deal internally with:
* -read errors when reading from drive
- * -bio_advance() calls during l2p lookup and cache reads
+ * -bio_advance() calls during cache reads
*/
int_bio = bio_clone_fast(bio, GFP_KERNEL, &pblk_bio_set);
if (nr_secs > 1)
- pblk_read_ppalist_rq(pblk, rqd, bio, blba, read_bitmap);
+ nr_secs = pblk_read_ppalist_rq(pblk, rqd, int_bio, blba,
+ &from_cache);
else
- pblk_read_rq(pblk, rqd, bio, blba, read_bitmap);
+ pblk_read_rq(pblk, rqd, int_bio, blba, &from_cache);
+split_retry:
r_ctx->private = bio; /* original bio */
rqd->bio = int_bio; /* internal bio */
- if (bitmap_full(read_bitmap, nr_secs)) {
+ if (from_cache && nr_secs == rqd->nr_ppas) {
+ /* All data was read from cache, we can complete the IO. */
pblk_end_user_read(bio, 0);
atomic_inc(&pblk->inflight_io);
__pblk_end_io_read(pblk, rqd, false);
- return;
- }
-
- if (!bitmap_empty(read_bitmap, rqd->nr_ppas)) {
+ } else if (nr_secs != rqd->nr_ppas) {
/* The read bio request could be partially filled by the write
* buffer, but there are some holes that need to be read from
- * the drive.
+ * the drive. In order to handle this, we will use block layer
+ * mechanism to split this request in to smaller ones and make
+ * a chain of it.
*/
- bio_put(int_bio);
- rqd->bio = NULL;
- if (pblk_partial_read_bio(pblk, rqd, bio_init_idx, read_bitmap,
- nr_secs)) {
- pblk_err(pblk, "read IO submission failed\n");
- bio_io_error(bio);
- __pblk_end_io_read(pblk, rqd, false);
- }
- return;
- }
+ split_bio = bio_split(bio, nr_secs * NR_PHY_IN_LOG, GFP_KERNEL,
+ &pblk_bio_set);
+ bio_chain(split_bio, bio);
+ generic_make_request(bio);
+
+ /* New bio contains first N sectors of the previous one, so
+ * we can continue to use existing rqd, but we need to shrink
+ * the number of PPAs in it. New bio is also guaranteed that
+ * it contains only either data from cache or from drive, newer
+ * mix of them.
+ */
+ bio = split_bio;
+ rqd->nr_ppas = nr_secs;
+ if (rqd->nr_ppas == 1)
+ rqd->ppa_addr = rqd->ppa_list[0];
- /* All sectors are to be read from the device */
- if (pblk_submit_io(pblk, rqd)) {
- pblk_err(pblk, "read IO submission failed\n");
- bio_io_error(bio);
- __pblk_end_io_read(pblk, rqd, false);
+ /* Recreate int_bio - existing might have some needed internal
+ * fields modified already.
+ */
+ bio_put(int_bio);
+ int_bio = bio_clone_fast(bio, GFP_KERNEL, &pblk_bio_set);
+ goto split_retry;
+ } else if (pblk_submit_io(pblk, rqd)) {
+ /* Submitting IO to drive failed, let's report an error */
+ rqd->error = -ENODEV;
+ pblk_end_io_read(rqd);
}
}
projects / users / jedix / linux-maple.git / commitdiff