diff options
Diffstat (limited to 'drivers/lightnvm/pblk-rb.c')
| -rw-r--r-- | drivers/lightnvm/pblk-rb.c | 110 |
1 files changed, 54 insertions, 56 deletions
diff --git a/drivers/lightnvm/pblk-rb.c b/drivers/lightnvm/pblk-rb.c index f6eec0212dfc..b1f4b51783f4 100644 --- a/drivers/lightnvm/pblk-rb.c +++ b/drivers/lightnvm/pblk-rb.c @@ -1,3 +1,4 @@ +// SPDX-License-Identifier: GPL-2.0 /* * Copyright (C) 2016 CNEX Labs * Initial release: Javier Gonzalez <javier@cnexlabs.com> @@ -22,7 +23,7 @@ static DECLARE_RWSEM(pblk_rb_lock); -void pblk_rb_data_free(struct pblk_rb *rb) +static void pblk_rb_data_free(struct pblk_rb *rb) { struct pblk_rb_pages *p, *t; @@ -35,25 +36,51 @@ void pblk_rb_data_free(struct pblk_rb *rb) up_write(&pblk_rb_lock); } +void pblk_rb_free(struct pblk_rb *rb) +{ + pblk_rb_data_free(rb); + vfree(rb->entries); +} + +/* + * pblk_rb_calculate_size -- calculate the size of the write buffer + */ +static unsigned int pblk_rb_calculate_size(unsigned int nr_entries) +{ + /* Alloc a write buffer that can at least fit 128 entries */ + return (1 << max(get_count_order(nr_entries), 7)); +} + /* * Initialize ring buffer. The data and metadata buffers must be previously * allocated and their size must be a power of two * (Documentation/core-api/circular-buffers.rst) */ -int pblk_rb_init(struct pblk_rb *rb, struct pblk_rb_entry *rb_entry_base, - unsigned int power_size, unsigned int power_seg_sz) +int pblk_rb_init(struct pblk_rb *rb, unsigned int size, unsigned int threshold, + unsigned int seg_size) { struct pblk *pblk = container_of(rb, struct pblk, rwb); + struct pblk_rb_entry *entries; unsigned int init_entry = 0; - unsigned int alloc_order = power_size; unsigned int max_order = MAX_ORDER - 1; - unsigned int order, iter; + unsigned int power_size, power_seg_sz; + unsigned int alloc_order, order, iter; + unsigned int nr_entries; + + nr_entries = pblk_rb_calculate_size(size); + entries = vzalloc(array_size(nr_entries, sizeof(struct pblk_rb_entry))); + if (!entries) + return -ENOMEM; + + power_size = get_count_order(size); + power_seg_sz = get_count_order(seg_size); down_write(&pblk_rb_lock); - rb->entries = rb_entry_base; + rb->entries = entries; rb->seg_size = (1 << power_seg_sz); rb->nr_entries = (1 << power_size); rb->mem = rb->subm = rb->sync = rb->l2p_update = 0; + rb->back_thres = threshold; rb->flush_point = EMPTY_ENTRY; spin_lock_init(&rb->w_lock); @@ -61,6 +88,7 @@ int pblk_rb_init(struct pblk_rb *rb, struct pblk_rb_entry *rb_entry_base, INIT_LIST_HEAD(&rb->pages); + alloc_order = power_size; if (alloc_order >= max_order) { order = max_order; iter = (1 << (alloc_order - max_order)); @@ -79,6 +107,7 @@ int pblk_rb_init(struct pblk_rb *rb, struct pblk_rb_entry *rb_entry_base, page_set = kmalloc(sizeof(struct pblk_rb_pages), GFP_KERNEL); if (!page_set) { up_write(&pblk_rb_lock); + vfree(entries); return -ENOMEM; } @@ -88,6 +117,7 @@ int pblk_rb_init(struct pblk_rb *rb, struct pblk_rb_entry *rb_entry_base, kfree(page_set); pblk_rb_data_free(rb); up_write(&pblk_rb_lock); + vfree(entries); return -ENOMEM; } kaddr = page_address(page_set->pages); @@ -124,20 +154,6 @@ int pblk_rb_init(struct pblk_rb *rb, struct pblk_rb_entry *rb_entry_base, return 0; } -/* - * pblk_rb_calculate_size -- calculate the size of the write buffer - */ -unsigned int pblk_rb_calculate_size(unsigned int nr_entries) -{ - /* Alloc a write buffer that can at least fit 128 entries */ - return (1 << max(get_count_order(nr_entries), 7)); -} - -void *pblk_rb_entries_ref(struct pblk_rb *rb) -{ - return rb->entries; -} - static void clean_wctx(struct pblk_w_ctx *w_ctx) { int flags; @@ -168,6 +184,12 @@ static unsigned int pblk_rb_space(struct pblk_rb *rb) return pblk_rb_ring_space(rb, mem, sync, rb->nr_entries); } +unsigned int pblk_rb_ptr_wrap(struct pblk_rb *rb, unsigned int p, + unsigned int nr_entries) +{ + return (p + nr_entries) & (rb->nr_entries - 1); +} + /* * Buffer count is calculated with respect to the submission entry signaling the * entries that are available to send to the media @@ -194,8 +216,7 @@ unsigned int pblk_rb_read_commit(struct pblk_rb *rb, unsigned int nr_entries) subm = READ_ONCE(rb->subm); /* Commit read means updating submission pointer */ - smp_store_release(&rb->subm, - (subm + nr_entries) & (rb->nr_entries - 1)); + smp_store_release(&rb->subm, pblk_rb_ptr_wrap(rb, subm, nr_entries)); return subm; } @@ -225,10 +246,10 @@ static int __pblk_rb_update_l2p(struct pblk_rb *rb, unsigned int to_update) pblk_update_map_dev(pblk, w_ctx->lba, w_ctx->ppa, entry->cacheline); - line = &pblk->lines[pblk_ppa_to_line(w_ctx->ppa)]; + line = pblk_ppa_to_line(pblk, w_ctx->ppa); kref_put(&line->ref, pblk_line_put); clean_wctx(w_ctx); - rb->l2p_update = (rb->l2p_update + 1) & (rb->nr_entries - 1); + rb->l2p_update = pblk_rb_ptr_wrap(rb, rb->l2p_update, 1); } pblk_rl_out(&pblk->rl, user_io, gc_io); @@ -385,11 +406,14 @@ static int __pblk_rb_may_write(struct pblk_rb *rb, unsigned int nr_entries, { unsigned int mem; unsigned int sync; + unsigned int threshold; sync = READ_ONCE(rb->sync); mem = READ_ONCE(rb->mem); - if (pblk_rb_ring_space(rb, mem, sync, rb->nr_entries) < nr_entries) + threshold = nr_entries + rb->back_thres; + + if (pblk_rb_ring_space(rb, mem, sync, rb->nr_entries) < threshold) return 0; if (pblk_rb_update_l2p(rb, nr_entries, mem, sync)) @@ -407,7 +431,7 @@ static int pblk_rb_may_write(struct pblk_rb *rb, unsigned int nr_entries, return 0; /* Protect from read count */ - smp_store_release(&rb->mem, (*pos + nr_entries) & (rb->nr_entries - 1)); + smp_store_release(&rb->mem, pblk_rb_ptr_wrap(rb, *pos, nr_entries)); return 1; } @@ -431,7 +455,7 @@ static int pblk_rb_may_write_flush(struct pblk_rb *rb, unsigned int nr_entries, if (!__pblk_rb_may_write(rb, nr_entries, pos)) return 0; - mem = (*pos + nr_entries) & (rb->nr_entries - 1); + mem = pblk_rb_ptr_wrap(rb, *pos, nr_entries); *io_ret = NVM_IO_DONE; if (bio->bi_opf & REQ_PREFLUSH) { @@ -571,7 +595,7 @@ try: /* Release flags on context. Protect from writes */ smp_store_release(&entry->w_ctx.flags, flags); - pos = (pos + 1) & (rb->nr_entries - 1); + pos = pblk_rb_ptr_wrap(rb, pos, 1); } if (pad) { @@ -651,7 +675,7 @@ out: struct pblk_w_ctx *pblk_rb_w_ctx(struct pblk_rb *rb, unsigned int pos) { - unsigned int entry = pos & (rb->nr_entries - 1); + unsigned int entry = pblk_rb_ptr_wrap(rb, pos, 0); return &rb->entries[entry].w_ctx; } @@ -697,7 +721,7 @@ unsigned int pblk_rb_sync_advance(struct pblk_rb *rb, unsigned int nr_entries) } } - sync = (sync + nr_entries) & (rb->nr_entries - 1); + sync = pblk_rb_ptr_wrap(rb, sync, nr_entries); /* Protect from counts */ smp_store_release(&rb->sync, sync); @@ -728,32 +752,6 @@ unsigned int pblk_rb_flush_point_count(struct pblk_rb *rb) return (submitted < to_flush) ? (to_flush - submitted) : 0; } -/* - * Scan from the current position of the sync pointer to find the entry that - * corresponds to the given ppa. This is necessary since write requests can be - * completed out of order. The assumption is that the ppa is close to the sync - * pointer thus the search will not take long. - * - * The caller of this function must guarantee that the sync pointer will no - * reach the entry while it is using the metadata associated with it. With this - * assumption in mind, there is no need to take the sync lock. - */ -struct pblk_rb_entry *pblk_rb_sync_scan_entry(struct pblk_rb *rb, - struct ppa_addr *ppa) -{ - unsigned int sync, subm, count; - unsigned int i; - - sync = READ_ONCE(rb->sync); - subm = READ_ONCE(rb->subm); - count = pblk_rb_ring_count(subm, sync, rb->nr_entries); - - for (i = 0; i < count; i++) - sync = (sync + 1) & (rb->nr_entries - 1); - - return NULL; -} - int pblk_rb_tear_down_check(struct pblk_rb *rb) { struct pblk_rb_entry *entry; |