diff options
Diffstat (limited to 'drivers/lightnvm/pblk-rb.c')
-rw-r--r-- | drivers/lightnvm/pblk-rb.c | 852 |
1 files changed, 852 insertions, 0 deletions
diff --git a/drivers/lightnvm/pblk-rb.c b/drivers/lightnvm/pblk-rb.c new file mode 100644 index 000000000000..045384ddc1f9 --- /dev/null +++ b/drivers/lightnvm/pblk-rb.c @@ -0,0 +1,852 @@ +/* + * Copyright (C) 2016 CNEX Labs + * Initial release: Javier Gonzalez <javier@cnexlabs.com> + * + * Based upon the circular ringbuffer. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License version + * 2 as published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * pblk-rb.c - pblk's write buffer + */ + +#include <linux/circ_buf.h> + +#include "pblk.h" + +static DECLARE_RWSEM(pblk_rb_lock); + +void pblk_rb_data_free(struct pblk_rb *rb) +{ + struct pblk_rb_pages *p, *t; + + down_write(&pblk_rb_lock); + list_for_each_entry_safe(p, t, &rb->pages, list) { + free_pages((unsigned long)page_address(p->pages), p->order); + list_del(&p->list); + kfree(p); + } + up_write(&pblk_rb_lock); +} + +/* + * Initialize ring buffer. The data and metadata buffers must be previously + * allocated and their size must be a power of two + * (Documentation/circular-buffers.txt) + */ +int pblk_rb_init(struct pblk_rb *rb, struct pblk_rb_entry *rb_entry_base, + unsigned int power_size, unsigned int power_seg_sz) +{ + struct pblk *pblk = container_of(rb, struct pblk, rwb); + unsigned int init_entry = 0; + unsigned int alloc_order = power_size; + unsigned int max_order = MAX_ORDER - 1; + unsigned int order, iter; + + down_write(&pblk_rb_lock); + rb->entries = rb_entry_base; + rb->seg_size = (1 << power_seg_sz); + rb->nr_entries = (1 << power_size); + rb->mem = rb->subm = rb->sync = rb->l2p_update = 0; + rb->sync_point = EMPTY_ENTRY; + + spin_lock_init(&rb->w_lock); + spin_lock_init(&rb->s_lock); + + INIT_LIST_HEAD(&rb->pages); + + if (alloc_order >= max_order) { + order = max_order; + iter = (1 << (alloc_order - max_order)); + } else { + order = alloc_order; + iter = 1; + } + + do { + struct pblk_rb_entry *entry; + struct pblk_rb_pages *page_set; + void *kaddr; + unsigned long set_size; + int i; + + page_set = kmalloc(sizeof(struct pblk_rb_pages), GFP_KERNEL); + if (!page_set) { + up_write(&pblk_rb_lock); + return -ENOMEM; + } + + page_set->order = order; + page_set->pages = alloc_pages(GFP_KERNEL, order); + if (!page_set->pages) { + kfree(page_set); + pblk_rb_data_free(rb); + up_write(&pblk_rb_lock); + return -ENOMEM; + } + kaddr = page_address(page_set->pages); + + entry = &rb->entries[init_entry]; + entry->data = kaddr; + entry->cacheline = pblk_cacheline_to_addr(init_entry++); + entry->w_ctx.flags = PBLK_WRITABLE_ENTRY; + + set_size = (1 << order); + for (i = 1; i < set_size; i++) { + entry = &rb->entries[init_entry]; + entry->cacheline = pblk_cacheline_to_addr(init_entry++); + entry->data = kaddr + (i * rb->seg_size); + entry->w_ctx.flags = PBLK_WRITABLE_ENTRY; + bio_list_init(&entry->w_ctx.bios); + } + + list_add_tail(&page_set->list, &rb->pages); + iter--; + } while (iter > 0); + up_write(&pblk_rb_lock); + +#ifdef CONFIG_NVM_DEBUG + atomic_set(&rb->inflight_sync_point, 0); +#endif + + /* + * Initialize rate-limiter, which controls access to the write buffer + * but user and GC I/O + */ + pblk_rl_init(&pblk->rl, rb->nr_entries); + + 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; + +try: + flags = READ_ONCE(w_ctx->flags); + if (!(flags & PBLK_SUBMITTED_ENTRY)) + goto try; + + /* Release flags on context. Protect from writes and reads */ + smp_store_release(&w_ctx->flags, PBLK_WRITABLE_ENTRY); + pblk_ppa_set_empty(&w_ctx->ppa); +} + +#define pblk_rb_ring_count(head, tail, size) CIRC_CNT(head, tail, size) +#define pblk_rb_ring_space(rb, head, tail, size) \ + (CIRC_SPACE(head, tail, size)) + +/* + * Buffer space is calculated with respect to the back pointer signaling + * synchronized entries to the media. + */ +static unsigned int pblk_rb_space(struct pblk_rb *rb) +{ + unsigned int mem = READ_ONCE(rb->mem); + unsigned int sync = READ_ONCE(rb->sync); + + return pblk_rb_ring_space(rb, mem, sync, rb->nr_entries); +} + +/* + * Buffer count is calculated with respect to the submission entry signaling the + * entries that are available to send to the media + */ +unsigned int pblk_rb_read_count(struct pblk_rb *rb) +{ + unsigned int mem = READ_ONCE(rb->mem); + unsigned int subm = READ_ONCE(rb->subm); + + return pblk_rb_ring_count(mem, subm, rb->nr_entries); +} + +unsigned int pblk_rb_read_commit(struct pblk_rb *rb, unsigned int nr_entries) +{ + unsigned int subm; + + subm = READ_ONCE(rb->subm); + /* Commit read means updating submission pointer */ + smp_store_release(&rb->subm, + (subm + nr_entries) & (rb->nr_entries - 1)); + + return subm; +} + +static int __pblk_rb_update_l2p(struct pblk_rb *rb, unsigned int *l2p_upd, + unsigned int to_update) +{ + struct pblk *pblk = container_of(rb, struct pblk, rwb); + struct pblk_line *line; + struct pblk_rb_entry *entry; + struct pblk_w_ctx *w_ctx; + unsigned int i; + + for (i = 0; i < to_update; i++) { + entry = &rb->entries[*l2p_upd]; + w_ctx = &entry->w_ctx; + + pblk_update_map_dev(pblk, w_ctx->lba, w_ctx->ppa, + entry->cacheline); + + line = &pblk->lines[pblk_tgt_ppa_to_line(w_ctx->ppa)]; + kref_put(&line->ref, pblk_line_put); + clean_wctx(w_ctx); + *l2p_upd = (*l2p_upd + 1) & (rb->nr_entries - 1); + } + + return 0; +} + +/* + * When we move the l2p_update pointer, we update the l2p table - lookups will + * point to the physical address instead of to the cacheline in the write buffer + * from this moment on. + */ +static int pblk_rb_update_l2p(struct pblk_rb *rb, unsigned int nr_entries, + unsigned int mem, unsigned int sync) +{ + unsigned int space, count; + int ret = 0; + + lockdep_assert_held(&rb->w_lock); + + /* Update l2p only as buffer entries are being overwritten */ + space = pblk_rb_ring_space(rb, mem, rb->l2p_update, rb->nr_entries); + if (space > nr_entries) + goto out; + + count = nr_entries - space; + /* l2p_update used exclusively under rb->w_lock */ + ret = __pblk_rb_update_l2p(rb, &rb->l2p_update, count); + +out: + return ret; +} + +/* + * Update the l2p entry for all sectors stored on the write buffer. This means + * that all future lookups to the l2p table will point to a device address, not + * to the cacheline in the write buffer. + */ +void pblk_rb_sync_l2p(struct pblk_rb *rb) +{ + unsigned int sync; + unsigned int to_update; + + spin_lock(&rb->w_lock); + + /* Protect from reads and writes */ + sync = smp_load_acquire(&rb->sync); + + to_update = pblk_rb_ring_count(sync, rb->l2p_update, rb->nr_entries); + __pblk_rb_update_l2p(rb, &rb->l2p_update, to_update); + + spin_unlock(&rb->w_lock); +} + +/* + * Write @nr_entries to ring buffer from @data buffer if there is enough space. + * Typically, 4KB data chunks coming from a bio will be copied to the ring + * buffer, thus the write will fail if not all incoming data can be copied. + * + */ +static void __pblk_rb_write_entry(struct pblk_rb *rb, void *data, + struct pblk_w_ctx w_ctx, + struct pblk_rb_entry *entry) +{ + memcpy(entry->data, data, rb->seg_size); + + entry->w_ctx.lba = w_ctx.lba; + entry->w_ctx.ppa = w_ctx.ppa; +} + +void pblk_rb_write_entry_user(struct pblk_rb *rb, void *data, + struct pblk_w_ctx w_ctx, unsigned int ring_pos) +{ + struct pblk *pblk = container_of(rb, struct pblk, rwb); + struct pblk_rb_entry *entry; + int flags; + + entry = &rb->entries[ring_pos]; + flags = READ_ONCE(entry->w_ctx.flags); +#ifdef CONFIG_NVM_DEBUG + /* Caller must guarantee that the entry is free */ + BUG_ON(!(flags & PBLK_WRITABLE_ENTRY)); +#endif + + __pblk_rb_write_entry(rb, data, w_ctx, entry); + + pblk_update_map_cache(pblk, w_ctx.lba, entry->cacheline); + flags = w_ctx.flags | PBLK_WRITTEN_DATA; + + /* Release flags on write context. Protect from writes */ + smp_store_release(&entry->w_ctx.flags, flags); +} + +void pblk_rb_write_entry_gc(struct pblk_rb *rb, void *data, + struct pblk_w_ctx w_ctx, struct pblk_line *gc_line, + unsigned int ring_pos) +{ + struct pblk *pblk = container_of(rb, struct pblk, rwb); + struct pblk_rb_entry *entry; + int flags; + + entry = &rb->entries[ring_pos]; + flags = READ_ONCE(entry->w_ctx.flags); +#ifdef CONFIG_NVM_DEBUG + /* Caller must guarantee that the entry is free */ + BUG_ON(!(flags & PBLK_WRITABLE_ENTRY)); +#endif + + __pblk_rb_write_entry(rb, data, w_ctx, entry); + + if (!pblk_update_map_gc(pblk, w_ctx.lba, entry->cacheline, gc_line)) + entry->w_ctx.lba = ADDR_EMPTY; + + flags = w_ctx.flags | PBLK_WRITTEN_DATA; + + /* Release flags on write context. Protect from writes */ + smp_store_release(&entry->w_ctx.flags, flags); +} + +static int pblk_rb_sync_point_set(struct pblk_rb *rb, struct bio *bio, + unsigned int pos) +{ + struct pblk_rb_entry *entry; + unsigned int subm, sync_point; + int flags; + + subm = READ_ONCE(rb->subm); + +#ifdef CONFIG_NVM_DEBUG + atomic_inc(&rb->inflight_sync_point); +#endif + + if (pos == subm) + return 0; + + sync_point = (pos == 0) ? (rb->nr_entries - 1) : (pos - 1); + entry = &rb->entries[sync_point]; + + flags = READ_ONCE(entry->w_ctx.flags); + flags |= PBLK_FLUSH_ENTRY; + + /* Release flags on context. Protect from writes */ + smp_store_release(&entry->w_ctx.flags, flags); + + /* Protect syncs */ + smp_store_release(&rb->sync_point, sync_point); + + spin_lock_irq(&rb->s_lock); + bio_list_add(&entry->w_ctx.bios, bio); + spin_unlock_irq(&rb->s_lock); + + return 1; +} + +static int __pblk_rb_may_write(struct pblk_rb *rb, unsigned int nr_entries, + unsigned int *pos) +{ + unsigned int mem; + unsigned int sync; + + sync = READ_ONCE(rb->sync); + mem = READ_ONCE(rb->mem); + + if (pblk_rb_ring_space(rb, mem, sync, rb->nr_entries) < nr_entries) + return 0; + + if (pblk_rb_update_l2p(rb, nr_entries, mem, sync)) + return 0; + + *pos = mem; + + return 1; +} + +static int pblk_rb_may_write(struct pblk_rb *rb, unsigned int nr_entries, + unsigned int *pos) +{ + if (!__pblk_rb_may_write(rb, nr_entries, pos)) + return 0; + + /* Protect from read count */ + smp_store_release(&rb->mem, (*pos + nr_entries) & (rb->nr_entries - 1)); + return 1; +} + +static int pblk_rb_may_write_flush(struct pblk_rb *rb, unsigned int nr_entries, + unsigned int *pos, struct bio *bio, + int *io_ret) +{ + unsigned int mem; + + if (!__pblk_rb_may_write(rb, nr_entries, pos)) + return 0; + + mem = (*pos + nr_entries) & (rb->nr_entries - 1); + *io_ret = NVM_IO_DONE; + + if (bio->bi_opf & REQ_PREFLUSH) { + struct pblk *pblk = container_of(rb, struct pblk, rwb); + +#ifdef CONFIG_NVM_DEBUG + atomic_long_inc(&pblk->nr_flush); +#endif + if (pblk_rb_sync_point_set(&pblk->rwb, bio, mem)) + *io_ret = NVM_IO_OK; + } + + /* Protect from read count */ + smp_store_release(&rb->mem, mem); + return 1; +} + +/* + * Atomically check that (i) there is space on the write buffer for the + * incoming I/O, and (ii) the current I/O type has enough budget in the write + * buffer (rate-limiter). + */ +int pblk_rb_may_write_user(struct pblk_rb *rb, struct bio *bio, + unsigned int nr_entries, unsigned int *pos) +{ + struct pblk *pblk = container_of(rb, struct pblk, rwb); + int flush_done; + + spin_lock(&rb->w_lock); + if (!pblk_rl_user_may_insert(&pblk->rl, nr_entries)) { + spin_unlock(&rb->w_lock); + return NVM_IO_REQUEUE; + } + + if (!pblk_rb_may_write_flush(rb, nr_entries, pos, bio, &flush_done)) { + spin_unlock(&rb->w_lock); + return NVM_IO_REQUEUE; + } + + pblk_rl_user_in(&pblk->rl, nr_entries); + spin_unlock(&rb->w_lock); + + return flush_done; +} + +/* + * Look at pblk_rb_may_write_user comment + */ +int pblk_rb_may_write_gc(struct pblk_rb *rb, unsigned int nr_entries, + unsigned int *pos) +{ + struct pblk *pblk = container_of(rb, struct pblk, rwb); + + spin_lock(&rb->w_lock); + if (!pblk_rl_gc_may_insert(&pblk->rl, nr_entries)) { + spin_unlock(&rb->w_lock); + return 0; + } + + if (!pblk_rb_may_write(rb, nr_entries, pos)) { + spin_unlock(&rb->w_lock); + return 0; + } + + pblk_rl_gc_in(&pblk->rl, nr_entries); + spin_unlock(&rb->w_lock); + + return 1; +} + +/* + * The caller of this function must ensure that the backpointer will not + * overwrite the entries passed on the list. + */ +unsigned int pblk_rb_read_to_bio_list(struct pblk_rb *rb, struct bio *bio, + struct list_head *list, + unsigned int max) +{ + struct pblk_rb_entry *entry, *tentry; + struct page *page; + unsigned int read = 0; + int ret; + + list_for_each_entry_safe(entry, tentry, list, index) { + if (read > max) { + pr_err("pblk: too many entries on list\n"); + goto out; + } + + page = virt_to_page(entry->data); + if (!page) { + pr_err("pblk: could not allocate write bio page\n"); + goto out; + } + + ret = bio_add_page(bio, page, rb->seg_size, 0); + if (ret != rb->seg_size) { + pr_err("pblk: could not add page to write bio\n"); + goto out; + } + + list_del(&entry->index); + read++; + } + +out: + return read; +} + +/* + * Read available entries on rb and add them to the given bio. To avoid a memory + * copy, a page reference to the write buffer is used to be added to the bio. + * + * This function is used by the write thread to form the write bio that will + * persist data on the write buffer to the media. + */ +unsigned int pblk_rb_read_to_bio(struct pblk_rb *rb, struct bio *bio, + struct pblk_c_ctx *c_ctx, + unsigned int pos, + unsigned int nr_entries, + unsigned int count) +{ + struct pblk *pblk = container_of(rb, struct pblk, rwb); + struct pblk_rb_entry *entry; + struct page *page; + unsigned int pad = 0, read = 0, to_read = nr_entries; + unsigned int user_io = 0, gc_io = 0; + unsigned int i; + int flags; + int ret; + + if (count < nr_entries) { + pad = nr_entries - count; + to_read = count; + } + + c_ctx->sentry = pos; + c_ctx->nr_valid = to_read; + c_ctx->nr_padded = pad; + + for (i = 0; i < to_read; i++) { + entry = &rb->entries[pos]; + + /* A write has been allowed into the buffer, but data is still + * being copied to it. It is ok to busy wait. + */ +try: + flags = READ_ONCE(entry->w_ctx.flags); + if (!(flags & PBLK_WRITTEN_DATA)) + goto try; + + if (flags & PBLK_IOTYPE_USER) + user_io++; + else if (flags & PBLK_IOTYPE_GC) + gc_io++; + else + WARN(1, "pblk: unknown IO type\n"); + + page = virt_to_page(entry->data); + if (!page) { + pr_err("pblk: could not allocate write bio page\n"); + flags &= ~PBLK_WRITTEN_DATA; + flags |= PBLK_SUBMITTED_ENTRY; + /* Release flags on context. Protect from writes */ + smp_store_release(&entry->w_ctx.flags, flags); + goto out; + } + + ret = bio_add_page(bio, page, rb->seg_size, 0); + if (ret != rb->seg_size) { + pr_err("pblk: could not add page to write bio\n"); + flags &= ~PBLK_WRITTEN_DATA; + flags |= PBLK_SUBMITTED_ENTRY; + /* Release flags on context. Protect from writes */ + smp_store_release(&entry->w_ctx.flags, flags); + goto out; + } + + if (flags & PBLK_FLUSH_ENTRY) { + unsigned int sync_point; + + sync_point = READ_ONCE(rb->sync_point); + if (sync_point == pos) { + /* Protect syncs */ + smp_store_release(&rb->sync_point, EMPTY_ENTRY); + } + + flags &= ~PBLK_FLUSH_ENTRY; +#ifdef CONFIG_NVM_DEBUG + atomic_dec(&rb->inflight_sync_point); +#endif + } + + flags &= ~PBLK_WRITTEN_DATA; + flags |= PBLK_SUBMITTED_ENTRY; + + /* Release flags on context. Protect from writes */ + smp_store_release(&entry->w_ctx.flags, flags); + + pos = (pos + 1) & (rb->nr_entries - 1); + } + + read = to_read; + pblk_rl_out(&pblk->rl, user_io, gc_io); +#ifdef CONFIG_NVM_DEBUG + atomic_long_add(pad, &((struct pblk *) + (container_of(rb, struct pblk, rwb)))->padded_writes); +#endif +out: + return read; +} + +/* + * Copy to bio only if the lba matches the one on the given cache entry. + * Otherwise, it means that the entry has been overwritten, and the bio should + * be directed to disk. + */ +int pblk_rb_copy_to_bio(struct pblk_rb *rb, struct bio *bio, sector_t lba, + u64 pos, int bio_iter) +{ + struct pblk_rb_entry *entry; + struct pblk_w_ctx *w_ctx; + void *data; + int flags; + int ret = 1; + + spin_lock(&rb->w_lock); + +#ifdef CONFIG_NVM_DEBUG + /* Caller must ensure that the access will not cause an overflow */ + BUG_ON(pos >= rb->nr_entries); +#endif + entry = &rb->entries[pos]; + w_ctx = &entry->w_ctx; + flags = READ_ONCE(w_ctx->flags); + + /* Check if the entry has been overwritten or is scheduled to be */ + if (w_ctx->lba != lba || flags & PBLK_WRITABLE_ENTRY) { + ret = 0; + goto out; + } + + /* Only advance the bio if it hasn't been advanced already. If advanced, + * this bio is at least a partial bio (i.e., it has partially been + * filled with data from the cache). If part of the data resides on the + * media, we will read later on + */ + if (unlikely(!bio->bi_iter.bi_idx)) + bio_advance(bio, bio_iter * PBLK_EXPOSED_PAGE_SIZE); + + data = bio_data(bio); + memcpy(data, entry->data, rb->seg_size); + +out: + spin_unlock(&rb->w_lock); + return ret; +} + +struct pblk_w_ctx *pblk_rb_w_ctx(struct pblk_rb *rb, unsigned int pos) +{ + unsigned int entry = pos & (rb->nr_entries - 1); + + return &rb->entries[entry].w_ctx; +} + +unsigned int pblk_rb_sync_init(struct pblk_rb *rb, unsigned long *flags) + __acquires(&rb->s_lock) +{ + if (flags) + spin_lock_irqsave(&rb->s_lock, *flags); + else + spin_lock_irq(&rb->s_lock); + + return rb->sync; +} + +void pblk_rb_sync_end(struct pblk_rb *rb, unsigned long *flags) + __releases(&rb->s_lock) +{ + lockdep_assert_held(&rb->s_lock); + + if (flags) + spin_unlock_irqrestore(&rb->s_lock, *flags); + else + spin_unlock_irq(&rb->s_lock); +} + +unsigned int pblk_rb_sync_advance(struct pblk_rb *rb, unsigned int nr_entries) +{ + unsigned int sync; + unsigned int i; + + lockdep_assert_held(&rb->s_lock); + + sync = READ_ONCE(rb->sync); + + for (i = 0; i < nr_entries; i++) + sync = (sync + 1) & (rb->nr_entries - 1); + + /* Protect from counts */ + smp_store_release(&rb->sync, sync); + + return sync; +} + +unsigned int pblk_rb_sync_point_count(struct pblk_rb *rb) +{ + unsigned int subm, sync_point; + unsigned int count; + + /* Protect syncs */ + sync_point = smp_load_acquire(&rb->sync_point); + if (sync_point == EMPTY_ENTRY) + return 0; + + subm = READ_ONCE(rb->subm); + + /* The sync point itself counts as a sector to sync */ + count = pblk_rb_ring_count(sync_point, subm, rb->nr_entries) + 1; + + return count; +} + +/* + * 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; + int i; + int ret = 0; + + spin_lock(&rb->w_lock); + spin_lock_irq(&rb->s_lock); + + if ((rb->mem == rb->subm) && (rb->subm == rb->sync) && + (rb->sync == rb->l2p_update) && + (rb->sync_point == EMPTY_ENTRY)) { + goto out; + } + + if (!rb->entries) { + ret = 1; + goto out; + } + + for (i = 0; i < rb->nr_entries; i++) { + entry = &rb->entries[i]; + + if (!entry->data) { + ret = 1; + goto out; + } + } + +out: + spin_unlock(&rb->w_lock); + spin_unlock_irq(&rb->s_lock); + + return ret; +} + +unsigned int pblk_rb_wrap_pos(struct pblk_rb *rb, unsigned int pos) +{ + return (pos & (rb->nr_entries - 1)); +} + +int pblk_rb_pos_oob(struct pblk_rb *rb, u64 pos) +{ + return (pos >= rb->nr_entries); +} + +ssize_t pblk_rb_sysfs(struct pblk_rb *rb, char *buf) +{ + struct pblk *pblk = container_of(rb, struct pblk, rwb); + struct pblk_c_ctx *c; + ssize_t offset; + int queued_entries = 0; + + spin_lock_irq(&rb->s_lock); + list_for_each_entry(c, &pblk->compl_list, list) + queued_entries++; + spin_unlock_irq(&rb->s_lock); + + if (rb->sync_point != EMPTY_ENTRY) + offset = scnprintf(buf, PAGE_SIZE, + "%u\t%u\t%u\t%u\t%u\t%u\t%u - %u/%u/%u - %d\n", + rb->nr_entries, + rb->mem, + rb->subm, + rb->sync, + rb->l2p_update, +#ifdef CONFIG_NVM_DEBUG + atomic_read(&rb->inflight_sync_point), +#else + 0, +#endif + rb->sync_point, + pblk_rb_read_count(rb), + pblk_rb_space(rb), + pblk_rb_sync_point_count(rb), + queued_entries); + else + offset = scnprintf(buf, PAGE_SIZE, + "%u\t%u\t%u\t%u\t%u\t%u\tNULL - %u/%u/%u - %d\n", + rb->nr_entries, + rb->mem, + rb->subm, + rb->sync, + rb->l2p_update, +#ifdef CONFIG_NVM_DEBUG + atomic_read(&rb->inflight_sync_point), +#else + 0, +#endif + pblk_rb_read_count(rb), + pblk_rb_space(rb), + pblk_rb_sync_point_count(rb), + queued_entries); + + return offset; +} |