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-rw-r--r--drivers/md/persistent-data/dm-space-map-common.c1265
1 files changed, 1265 insertions, 0 deletions
diff --git a/drivers/md/persistent-data/dm-space-map-common.c b/drivers/md/persistent-data/dm-space-map-common.c
new file mode 100644
index 0000000000..591d1a43d0
--- /dev/null
+++ b/drivers/md/persistent-data/dm-space-map-common.c
@@ -0,0 +1,1265 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2011 Red Hat, Inc.
+ *
+ * This file is released under the GPL.
+ */
+
+#include "dm-space-map-common.h"
+#include "dm-transaction-manager.h"
+#include "dm-btree-internal.h"
+#include "dm-persistent-data-internal.h"
+
+#include <linux/bitops.h>
+#include <linux/device-mapper.h>
+
+#define DM_MSG_PREFIX "space map common"
+
+/*----------------------------------------------------------------*/
+
+/*
+ * Index validator.
+ */
+#define INDEX_CSUM_XOR 160478
+
+static void index_prepare_for_write(struct dm_block_validator *v,
+ struct dm_block *b,
+ size_t block_size)
+{
+ struct disk_metadata_index *mi_le = dm_block_data(b);
+
+ mi_le->blocknr = cpu_to_le64(dm_block_location(b));
+ mi_le->csum = cpu_to_le32(dm_bm_checksum(&mi_le->padding,
+ block_size - sizeof(__le32),
+ INDEX_CSUM_XOR));
+}
+
+static int index_check(struct dm_block_validator *v,
+ struct dm_block *b,
+ size_t block_size)
+{
+ struct disk_metadata_index *mi_le = dm_block_data(b);
+ __le32 csum_disk;
+
+ if (dm_block_location(b) != le64_to_cpu(mi_le->blocknr)) {
+ DMERR_LIMIT("%s failed: blocknr %llu != wanted %llu", __func__,
+ le64_to_cpu(mi_le->blocknr), dm_block_location(b));
+ return -ENOTBLK;
+ }
+
+ csum_disk = cpu_to_le32(dm_bm_checksum(&mi_le->padding,
+ block_size - sizeof(__le32),
+ INDEX_CSUM_XOR));
+ if (csum_disk != mi_le->csum) {
+ DMERR_LIMIT("i%s failed: csum %u != wanted %u", __func__,
+ le32_to_cpu(csum_disk), le32_to_cpu(mi_le->csum));
+ return -EILSEQ;
+ }
+
+ return 0;
+}
+
+static struct dm_block_validator index_validator = {
+ .name = "index",
+ .prepare_for_write = index_prepare_for_write,
+ .check = index_check
+};
+
+/*----------------------------------------------------------------*/
+
+/*
+ * Bitmap validator
+ */
+#define BITMAP_CSUM_XOR 240779
+
+static void dm_bitmap_prepare_for_write(struct dm_block_validator *v,
+ struct dm_block *b,
+ size_t block_size)
+{
+ struct disk_bitmap_header *disk_header = dm_block_data(b);
+
+ disk_header->blocknr = cpu_to_le64(dm_block_location(b));
+ disk_header->csum = cpu_to_le32(dm_bm_checksum(&disk_header->not_used,
+ block_size - sizeof(__le32),
+ BITMAP_CSUM_XOR));
+}
+
+static int dm_bitmap_check(struct dm_block_validator *v,
+ struct dm_block *b,
+ size_t block_size)
+{
+ struct disk_bitmap_header *disk_header = dm_block_data(b);
+ __le32 csum_disk;
+
+ if (dm_block_location(b) != le64_to_cpu(disk_header->blocknr)) {
+ DMERR_LIMIT("bitmap check failed: blocknr %llu != wanted %llu",
+ le64_to_cpu(disk_header->blocknr), dm_block_location(b));
+ return -ENOTBLK;
+ }
+
+ csum_disk = cpu_to_le32(dm_bm_checksum(&disk_header->not_used,
+ block_size - sizeof(__le32),
+ BITMAP_CSUM_XOR));
+ if (csum_disk != disk_header->csum) {
+ DMERR_LIMIT("bitmap check failed: csum %u != wanted %u",
+ le32_to_cpu(csum_disk), le32_to_cpu(disk_header->csum));
+ return -EILSEQ;
+ }
+
+ return 0;
+}
+
+static struct dm_block_validator dm_sm_bitmap_validator = {
+ .name = "sm_bitmap",
+ .prepare_for_write = dm_bitmap_prepare_for_write,
+ .check = dm_bitmap_check,
+};
+
+/*----------------------------------------------------------------*/
+
+#define ENTRIES_PER_WORD 32
+#define ENTRIES_SHIFT 5
+
+static void *dm_bitmap_data(struct dm_block *b)
+{
+ return dm_block_data(b) + sizeof(struct disk_bitmap_header);
+}
+
+#define WORD_MASK_HIGH 0xAAAAAAAAAAAAAAAAULL
+
+static unsigned int dm_bitmap_word_used(void *addr, unsigned int b)
+{
+ __le64 *words_le = addr;
+ __le64 *w_le = words_le + (b >> ENTRIES_SHIFT);
+
+ uint64_t bits = le64_to_cpu(*w_le);
+ uint64_t mask = (bits + WORD_MASK_HIGH + 1) & WORD_MASK_HIGH;
+
+ return !(~bits & mask);
+}
+
+static unsigned int sm_lookup_bitmap(void *addr, unsigned int b)
+{
+ __le64 *words_le = addr;
+ __le64 *w_le = words_le + (b >> ENTRIES_SHIFT);
+ unsigned int hi, lo;
+
+ b = (b & (ENTRIES_PER_WORD - 1)) << 1;
+ hi = !!test_bit_le(b, (void *) w_le);
+ lo = !!test_bit_le(b + 1, (void *) w_le);
+ return (hi << 1) | lo;
+}
+
+static void sm_set_bitmap(void *addr, unsigned int b, unsigned int val)
+{
+ __le64 *words_le = addr;
+ __le64 *w_le = words_le + (b >> ENTRIES_SHIFT);
+
+ b = (b & (ENTRIES_PER_WORD - 1)) << 1;
+
+ if (val & 2)
+ __set_bit_le(b, (void *) w_le);
+ else
+ __clear_bit_le(b, (void *) w_le);
+
+ if (val & 1)
+ __set_bit_le(b + 1, (void *) w_le);
+ else
+ __clear_bit_le(b + 1, (void *) w_le);
+}
+
+static int sm_find_free(void *addr, unsigned int begin, unsigned int end,
+ unsigned int *result)
+{
+ while (begin < end) {
+ if (!(begin & (ENTRIES_PER_WORD - 1)) &&
+ dm_bitmap_word_used(addr, begin)) {
+ begin += ENTRIES_PER_WORD;
+ continue;
+ }
+
+ if (!sm_lookup_bitmap(addr, begin)) {
+ *result = begin;
+ return 0;
+ }
+
+ begin++;
+ }
+
+ return -ENOSPC;
+}
+
+/*----------------------------------------------------------------*/
+
+static int sm_ll_init(struct ll_disk *ll, struct dm_transaction_manager *tm)
+{
+ memset(ll, 0, sizeof(struct ll_disk));
+
+ ll->tm = tm;
+
+ ll->bitmap_info.tm = tm;
+ ll->bitmap_info.levels = 1;
+
+ /*
+ * Because the new bitmap blocks are created via a shadow
+ * operation, the old entry has already had its reference count
+ * decremented and we don't need the btree to do any bookkeeping.
+ */
+ ll->bitmap_info.value_type.size = sizeof(struct disk_index_entry);
+ ll->bitmap_info.value_type.inc = NULL;
+ ll->bitmap_info.value_type.dec = NULL;
+ ll->bitmap_info.value_type.equal = NULL;
+
+ ll->ref_count_info.tm = tm;
+ ll->ref_count_info.levels = 1;
+ ll->ref_count_info.value_type.size = sizeof(uint32_t);
+ ll->ref_count_info.value_type.inc = NULL;
+ ll->ref_count_info.value_type.dec = NULL;
+ ll->ref_count_info.value_type.equal = NULL;
+
+ ll->block_size = dm_bm_block_size(dm_tm_get_bm(tm));
+
+ if (ll->block_size > (1 << 30)) {
+ DMERR("block size too big to hold bitmaps");
+ return -EINVAL;
+ }
+
+ ll->entries_per_block = (ll->block_size - sizeof(struct disk_bitmap_header)) *
+ ENTRIES_PER_BYTE;
+ ll->nr_blocks = 0;
+ ll->bitmap_root = 0;
+ ll->ref_count_root = 0;
+ ll->bitmap_index_changed = false;
+
+ return 0;
+}
+
+int sm_ll_extend(struct ll_disk *ll, dm_block_t extra_blocks)
+{
+ int r;
+ dm_block_t i, nr_blocks, nr_indexes;
+ unsigned int old_blocks, blocks;
+
+ nr_blocks = ll->nr_blocks + extra_blocks;
+ old_blocks = dm_sector_div_up(ll->nr_blocks, ll->entries_per_block);
+ blocks = dm_sector_div_up(nr_blocks, ll->entries_per_block);
+
+ nr_indexes = dm_sector_div_up(nr_blocks, ll->entries_per_block);
+ if (nr_indexes > ll->max_entries(ll)) {
+ DMERR("space map too large");
+ return -EINVAL;
+ }
+
+ /*
+ * We need to set this before the dm_tm_new_block() call below.
+ */
+ ll->nr_blocks = nr_blocks;
+ for (i = old_blocks; i < blocks; i++) {
+ struct dm_block *b;
+ struct disk_index_entry idx;
+
+ r = dm_tm_new_block(ll->tm, &dm_sm_bitmap_validator, &b);
+ if (r < 0)
+ return r;
+
+ idx.blocknr = cpu_to_le64(dm_block_location(b));
+
+ dm_tm_unlock(ll->tm, b);
+
+ idx.nr_free = cpu_to_le32(ll->entries_per_block);
+ idx.none_free_before = 0;
+
+ r = ll->save_ie(ll, i, &idx);
+ if (r < 0)
+ return r;
+ }
+
+ return 0;
+}
+
+int sm_ll_lookup_bitmap(struct ll_disk *ll, dm_block_t b, uint32_t *result)
+{
+ int r;
+ dm_block_t index = b;
+ struct disk_index_entry ie_disk;
+ struct dm_block *blk;
+
+ if (b >= ll->nr_blocks) {
+ DMERR_LIMIT("metadata block out of bounds");
+ return -EINVAL;
+ }
+
+ b = do_div(index, ll->entries_per_block);
+ r = ll->load_ie(ll, index, &ie_disk);
+ if (r < 0)
+ return r;
+
+ r = dm_tm_read_lock(ll->tm, le64_to_cpu(ie_disk.blocknr),
+ &dm_sm_bitmap_validator, &blk);
+ if (r < 0)
+ return r;
+
+ *result = sm_lookup_bitmap(dm_bitmap_data(blk), b);
+
+ dm_tm_unlock(ll->tm, blk);
+
+ return 0;
+}
+
+static int sm_ll_lookup_big_ref_count(struct ll_disk *ll, dm_block_t b,
+ uint32_t *result)
+{
+ __le32 le_rc;
+ int r;
+
+ r = dm_btree_lookup(&ll->ref_count_info, ll->ref_count_root, &b, &le_rc);
+ if (r < 0)
+ return r;
+
+ *result = le32_to_cpu(le_rc);
+
+ return r;
+}
+
+int sm_ll_lookup(struct ll_disk *ll, dm_block_t b, uint32_t *result)
+{
+ int r = sm_ll_lookup_bitmap(ll, b, result);
+
+ if (r)
+ return r;
+
+ if (*result != 3)
+ return r;
+
+ return sm_ll_lookup_big_ref_count(ll, b, result);
+}
+
+int sm_ll_find_free_block(struct ll_disk *ll, dm_block_t begin,
+ dm_block_t end, dm_block_t *result)
+{
+ int r;
+ struct disk_index_entry ie_disk;
+ dm_block_t i, index_begin = begin;
+ dm_block_t index_end = dm_sector_div_up(end, ll->entries_per_block);
+
+ /*
+ * FIXME: Use shifts
+ */
+ begin = do_div(index_begin, ll->entries_per_block);
+ end = do_div(end, ll->entries_per_block);
+ if (end == 0)
+ end = ll->entries_per_block;
+
+ for (i = index_begin; i < index_end; i++, begin = 0) {
+ struct dm_block *blk;
+ unsigned int position;
+ uint32_t bit_end;
+
+ r = ll->load_ie(ll, i, &ie_disk);
+ if (r < 0)
+ return r;
+
+ if (le32_to_cpu(ie_disk.nr_free) == 0)
+ continue;
+
+ r = dm_tm_read_lock(ll->tm, le64_to_cpu(ie_disk.blocknr),
+ &dm_sm_bitmap_validator, &blk);
+ if (r < 0)
+ return r;
+
+ bit_end = (i == index_end - 1) ? end : ll->entries_per_block;
+
+ r = sm_find_free(dm_bitmap_data(blk),
+ max_t(unsigned int, begin, le32_to_cpu(ie_disk.none_free_before)),
+ bit_end, &position);
+ if (r == -ENOSPC) {
+ /*
+ * This might happen because we started searching
+ * part way through the bitmap.
+ */
+ dm_tm_unlock(ll->tm, blk);
+ continue;
+ }
+
+ dm_tm_unlock(ll->tm, blk);
+
+ *result = i * ll->entries_per_block + (dm_block_t) position;
+ return 0;
+ }
+
+ return -ENOSPC;
+}
+
+int sm_ll_find_common_free_block(struct ll_disk *old_ll, struct ll_disk *new_ll,
+ dm_block_t begin, dm_block_t end, dm_block_t *b)
+{
+ int r;
+ uint32_t count;
+
+ do {
+ r = sm_ll_find_free_block(new_ll, begin, new_ll->nr_blocks, b);
+ if (r)
+ break;
+
+ /* double check this block wasn't used in the old transaction */
+ if (*b >= old_ll->nr_blocks)
+ count = 0;
+ else {
+ r = sm_ll_lookup(old_ll, *b, &count);
+ if (r)
+ break;
+
+ if (count)
+ begin = *b + 1;
+ }
+ } while (count);
+
+ return r;
+}
+
+/*----------------------------------------------------------------*/
+
+int sm_ll_insert(struct ll_disk *ll, dm_block_t b,
+ uint32_t ref_count, int32_t *nr_allocations)
+{
+ int r;
+ uint32_t bit, old;
+ struct dm_block *nb;
+ dm_block_t index = b;
+ struct disk_index_entry ie_disk;
+ void *bm_le;
+ int inc;
+
+ bit = do_div(index, ll->entries_per_block);
+ r = ll->load_ie(ll, index, &ie_disk);
+ if (r < 0)
+ return r;
+
+ r = dm_tm_shadow_block(ll->tm, le64_to_cpu(ie_disk.blocknr),
+ &dm_sm_bitmap_validator, &nb, &inc);
+ if (r < 0) {
+ DMERR("dm_tm_shadow_block() failed");
+ return r;
+ }
+ ie_disk.blocknr = cpu_to_le64(dm_block_location(nb));
+ bm_le = dm_bitmap_data(nb);
+
+ old = sm_lookup_bitmap(bm_le, bit);
+ if (old > 2) {
+ r = sm_ll_lookup_big_ref_count(ll, b, &old);
+ if (r < 0) {
+ dm_tm_unlock(ll->tm, nb);
+ return r;
+ }
+ }
+
+ if (r) {
+ dm_tm_unlock(ll->tm, nb);
+ return r;
+ }
+
+ if (ref_count <= 2) {
+ sm_set_bitmap(bm_le, bit, ref_count);
+ dm_tm_unlock(ll->tm, nb);
+
+ if (old > 2) {
+ r = dm_btree_remove(&ll->ref_count_info,
+ ll->ref_count_root,
+ &b, &ll->ref_count_root);
+ if (r)
+ return r;
+ }
+
+ } else {
+ __le32 le_rc = cpu_to_le32(ref_count);
+
+ sm_set_bitmap(bm_le, bit, 3);
+ dm_tm_unlock(ll->tm, nb);
+
+ __dm_bless_for_disk(&le_rc);
+ r = dm_btree_insert(&ll->ref_count_info, ll->ref_count_root,
+ &b, &le_rc, &ll->ref_count_root);
+ if (r < 0) {
+ DMERR("ref count insert failed");
+ return r;
+ }
+ }
+
+ if (ref_count && !old) {
+ *nr_allocations = 1;
+ ll->nr_allocated++;
+ le32_add_cpu(&ie_disk.nr_free, -1);
+ if (le32_to_cpu(ie_disk.none_free_before) == bit)
+ ie_disk.none_free_before = cpu_to_le32(bit + 1);
+
+ } else if (old && !ref_count) {
+ *nr_allocations = -1;
+ ll->nr_allocated--;
+ le32_add_cpu(&ie_disk.nr_free, 1);
+ ie_disk.none_free_before = cpu_to_le32(min(le32_to_cpu(ie_disk.none_free_before), bit));
+ } else
+ *nr_allocations = 0;
+
+ return ll->save_ie(ll, index, &ie_disk);
+}
+
+/*----------------------------------------------------------------*/
+
+/*
+ * Holds useful intermediate results for the range based inc and dec
+ * operations.
+ */
+struct inc_context {
+ struct disk_index_entry ie_disk;
+ struct dm_block *bitmap_block;
+ void *bitmap;
+
+ struct dm_block *overflow_leaf;
+};
+
+static inline void init_inc_context(struct inc_context *ic)
+{
+ ic->bitmap_block = NULL;
+ ic->bitmap = NULL;
+ ic->overflow_leaf = NULL;
+}
+
+static inline void exit_inc_context(struct ll_disk *ll, struct inc_context *ic)
+{
+ if (ic->bitmap_block)
+ dm_tm_unlock(ll->tm, ic->bitmap_block);
+ if (ic->overflow_leaf)
+ dm_tm_unlock(ll->tm, ic->overflow_leaf);
+}
+
+static inline void reset_inc_context(struct ll_disk *ll, struct inc_context *ic)
+{
+ exit_inc_context(ll, ic);
+ init_inc_context(ic);
+}
+
+/*
+ * Confirms a btree node contains a particular key at an index.
+ */
+static bool contains_key(struct btree_node *n, uint64_t key, int index)
+{
+ return index >= 0 &&
+ index < le32_to_cpu(n->header.nr_entries) &&
+ le64_to_cpu(n->keys[index]) == key;
+}
+
+static int __sm_ll_inc_overflow(struct ll_disk *ll, dm_block_t b, struct inc_context *ic)
+{
+ int r;
+ int index;
+ struct btree_node *n;
+ __le32 *v_ptr;
+ uint32_t rc;
+
+ /*
+ * bitmap_block needs to be unlocked because getting the
+ * overflow_leaf may need to allocate, and thus use the space map.
+ */
+ reset_inc_context(ll, ic);
+
+ r = btree_get_overwrite_leaf(&ll->ref_count_info, ll->ref_count_root,
+ b, &index, &ll->ref_count_root, &ic->overflow_leaf);
+ if (r < 0)
+ return r;
+
+ n = dm_block_data(ic->overflow_leaf);
+
+ if (!contains_key(n, b, index)) {
+ DMERR("overflow btree is missing an entry");
+ return -EINVAL;
+ }
+
+ v_ptr = value_ptr(n, index);
+ rc = le32_to_cpu(*v_ptr) + 1;
+ *v_ptr = cpu_to_le32(rc);
+
+ return 0;
+}
+
+static int sm_ll_inc_overflow(struct ll_disk *ll, dm_block_t b, struct inc_context *ic)
+{
+ int index;
+ struct btree_node *n;
+ __le32 *v_ptr;
+ uint32_t rc;
+
+ /*
+ * Do we already have the correct overflow leaf?
+ */
+ if (ic->overflow_leaf) {
+ n = dm_block_data(ic->overflow_leaf);
+ index = lower_bound(n, b);
+ if (contains_key(n, b, index)) {
+ v_ptr = value_ptr(n, index);
+ rc = le32_to_cpu(*v_ptr) + 1;
+ *v_ptr = cpu_to_le32(rc);
+
+ return 0;
+ }
+ }
+
+ return __sm_ll_inc_overflow(ll, b, ic);
+}
+
+static inline int shadow_bitmap(struct ll_disk *ll, struct inc_context *ic)
+{
+ int r, inc;
+
+ r = dm_tm_shadow_block(ll->tm, le64_to_cpu(ic->ie_disk.blocknr),
+ &dm_sm_bitmap_validator, &ic->bitmap_block, &inc);
+ if (r < 0) {
+ DMERR("dm_tm_shadow_block() failed");
+ return r;
+ }
+ ic->ie_disk.blocknr = cpu_to_le64(dm_block_location(ic->bitmap_block));
+ ic->bitmap = dm_bitmap_data(ic->bitmap_block);
+ return 0;
+}
+
+/*
+ * Once shadow_bitmap has been called, which always happens at the start of inc/dec,
+ * we can reopen the bitmap with a simple write lock, rather than re calling
+ * dm_tm_shadow_block().
+ */
+static inline int ensure_bitmap(struct ll_disk *ll, struct inc_context *ic)
+{
+ if (!ic->bitmap_block) {
+ int r = dm_bm_write_lock(dm_tm_get_bm(ll->tm), le64_to_cpu(ic->ie_disk.blocknr),
+ &dm_sm_bitmap_validator, &ic->bitmap_block);
+ if (r) {
+ DMERR("unable to re-get write lock for bitmap");
+ return r;
+ }
+ ic->bitmap = dm_bitmap_data(ic->bitmap_block);
+ }
+
+ return 0;
+}
+
+/*
+ * Loops round incrementing entries in a single bitmap.
+ */
+static inline int sm_ll_inc_bitmap(struct ll_disk *ll, dm_block_t b,
+ uint32_t bit, uint32_t bit_end,
+ int32_t *nr_allocations, dm_block_t *new_b,
+ struct inc_context *ic)
+{
+ int r;
+ __le32 le_rc;
+ uint32_t old;
+
+ for (; bit != bit_end; bit++, b++) {
+ /*
+ * We only need to drop the bitmap if we need to find a new btree
+ * leaf for the overflow. So if it was dropped last iteration,
+ * we now re-get it.
+ */
+ r = ensure_bitmap(ll, ic);
+ if (r)
+ return r;
+
+ old = sm_lookup_bitmap(ic->bitmap, bit);
+ switch (old) {
+ case 0:
+ /* inc bitmap, adjust nr_allocated */
+ sm_set_bitmap(ic->bitmap, bit, 1);
+ (*nr_allocations)++;
+ ll->nr_allocated++;
+ le32_add_cpu(&ic->ie_disk.nr_free, -1);
+ if (le32_to_cpu(ic->ie_disk.none_free_before) == bit)
+ ic->ie_disk.none_free_before = cpu_to_le32(bit + 1);
+ break;
+
+ case 1:
+ /* inc bitmap */
+ sm_set_bitmap(ic->bitmap, bit, 2);
+ break;
+
+ case 2:
+ /* inc bitmap and insert into overflow */
+ sm_set_bitmap(ic->bitmap, bit, 3);
+ reset_inc_context(ll, ic);
+
+ le_rc = cpu_to_le32(3);
+ __dm_bless_for_disk(&le_rc);
+ r = dm_btree_insert(&ll->ref_count_info, ll->ref_count_root,
+ &b, &le_rc, &ll->ref_count_root);
+ if (r < 0) {
+ DMERR("ref count insert failed");
+ return r;
+ }
+ break;
+
+ default:
+ /*
+ * inc within the overflow tree only.
+ */
+ r = sm_ll_inc_overflow(ll, b, ic);
+ if (r < 0)
+ return r;
+ }
+ }
+
+ *new_b = b;
+ return 0;
+}
+
+/*
+ * Finds a bitmap that contains entries in the block range, and increments
+ * them.
+ */
+static int __sm_ll_inc(struct ll_disk *ll, dm_block_t b, dm_block_t e,
+ int32_t *nr_allocations, dm_block_t *new_b)
+{
+ int r;
+ struct inc_context ic;
+ uint32_t bit, bit_end;
+ dm_block_t index = b;
+
+ init_inc_context(&ic);
+
+ bit = do_div(index, ll->entries_per_block);
+ r = ll->load_ie(ll, index, &ic.ie_disk);
+ if (r < 0)
+ return r;
+
+ r = shadow_bitmap(ll, &ic);
+ if (r)
+ return r;
+
+ bit_end = min(bit + (e - b), (dm_block_t) ll->entries_per_block);
+ r = sm_ll_inc_bitmap(ll, b, bit, bit_end, nr_allocations, new_b, &ic);
+
+ exit_inc_context(ll, &ic);
+
+ if (r)
+ return r;
+
+ return ll->save_ie(ll, index, &ic.ie_disk);
+}
+
+int sm_ll_inc(struct ll_disk *ll, dm_block_t b, dm_block_t e,
+ int32_t *nr_allocations)
+{
+ *nr_allocations = 0;
+ while (b != e) {
+ int r = __sm_ll_inc(ll, b, e, nr_allocations, &b);
+
+ if (r)
+ return r;
+ }
+
+ return 0;
+}
+
+/*----------------------------------------------------------------*/
+
+static int __sm_ll_del_overflow(struct ll_disk *ll, dm_block_t b,
+ struct inc_context *ic)
+{
+ reset_inc_context(ll, ic);
+ return dm_btree_remove(&ll->ref_count_info, ll->ref_count_root,
+ &b, &ll->ref_count_root);
+}
+
+static int __sm_ll_dec_overflow(struct ll_disk *ll, dm_block_t b,
+ struct inc_context *ic, uint32_t *old_rc)
+{
+ int r;
+ int index = -1;
+ struct btree_node *n;
+ __le32 *v_ptr;
+ uint32_t rc;
+
+ reset_inc_context(ll, ic);
+ r = btree_get_overwrite_leaf(&ll->ref_count_info, ll->ref_count_root,
+ b, &index, &ll->ref_count_root, &ic->overflow_leaf);
+ if (r < 0)
+ return r;
+
+ n = dm_block_data(ic->overflow_leaf);
+
+ if (!contains_key(n, b, index)) {
+ DMERR("overflow btree is missing an entry");
+ return -EINVAL;
+ }
+
+ v_ptr = value_ptr(n, index);
+ rc = le32_to_cpu(*v_ptr);
+ *old_rc = rc;
+
+ if (rc == 3)
+ return __sm_ll_del_overflow(ll, b, ic);
+
+ rc--;
+ *v_ptr = cpu_to_le32(rc);
+ return 0;
+}
+
+static int sm_ll_dec_overflow(struct ll_disk *ll, dm_block_t b,
+ struct inc_context *ic, uint32_t *old_rc)
+{
+ /*
+ * Do we already have the correct overflow leaf?
+ */
+ if (ic->overflow_leaf) {
+ int index;
+ struct btree_node *n;
+ __le32 *v_ptr;
+ uint32_t rc;
+
+ n = dm_block_data(ic->overflow_leaf);
+ index = lower_bound(n, b);
+ if (contains_key(n, b, index)) {
+ v_ptr = value_ptr(n, index);
+ rc = le32_to_cpu(*v_ptr);
+ *old_rc = rc;
+
+ if (rc > 3) {
+ rc--;
+ *v_ptr = cpu_to_le32(rc);
+ return 0;
+ } else {
+ return __sm_ll_del_overflow(ll, b, ic);
+ }
+
+ }
+ }
+
+ return __sm_ll_dec_overflow(ll, b, ic, old_rc);
+}
+
+/*
+ * Loops round incrementing entries in a single bitmap.
+ */
+static inline int sm_ll_dec_bitmap(struct ll_disk *ll, dm_block_t b,
+ uint32_t bit, uint32_t bit_end,
+ struct inc_context *ic,
+ int32_t *nr_allocations, dm_block_t *new_b)
+{
+ int r;
+ uint32_t old;
+
+ for (; bit != bit_end; bit++, b++) {
+ /*
+ * We only need to drop the bitmap if we need to find a new btree
+ * leaf for the overflow. So if it was dropped last iteration,
+ * we now re-get it.
+ */
+ r = ensure_bitmap(ll, ic);
+ if (r)
+ return r;
+
+ old = sm_lookup_bitmap(ic->bitmap, bit);
+ switch (old) {
+ case 0:
+ DMERR("unable to decrement block");
+ return -EINVAL;
+
+ case 1:
+ /* dec bitmap */
+ sm_set_bitmap(ic->bitmap, bit, 0);
+ (*nr_allocations)--;
+ ll->nr_allocated--;
+ le32_add_cpu(&ic->ie_disk.nr_free, 1);
+ ic->ie_disk.none_free_before =
+ cpu_to_le32(min(le32_to_cpu(ic->ie_disk.none_free_before), bit));
+ break;
+
+ case 2:
+ /* dec bitmap and insert into overflow */
+ sm_set_bitmap(ic->bitmap, bit, 1);
+ break;
+
+ case 3:
+ r = sm_ll_dec_overflow(ll, b, ic, &old);
+ if (r < 0)
+ return r;
+
+ if (old == 3) {
+ r = ensure_bitmap(ll, ic);
+ if (r)
+ return r;
+
+ sm_set_bitmap(ic->bitmap, bit, 2);
+ }
+ break;
+ }
+ }
+
+ *new_b = b;
+ return 0;
+}
+
+static int __sm_ll_dec(struct ll_disk *ll, dm_block_t b, dm_block_t e,
+ int32_t *nr_allocations, dm_block_t *new_b)
+{
+ int r;
+ uint32_t bit, bit_end;
+ struct inc_context ic;
+ dm_block_t index = b;
+
+ init_inc_context(&ic);
+
+ bit = do_div(index, ll->entries_per_block);
+ r = ll->load_ie(ll, index, &ic.ie_disk);
+ if (r < 0)
+ return r;
+
+ r = shadow_bitmap(ll, &ic);
+ if (r)
+ return r;
+
+ bit_end = min(bit + (e - b), (dm_block_t) ll->entries_per_block);
+ r = sm_ll_dec_bitmap(ll, b, bit, bit_end, &ic, nr_allocations, new_b);
+ exit_inc_context(ll, &ic);
+
+ if (r)
+ return r;
+
+ return ll->save_ie(ll, index, &ic.ie_disk);
+}
+
+int sm_ll_dec(struct ll_disk *ll, dm_block_t b, dm_block_t e,
+ int32_t *nr_allocations)
+{
+ *nr_allocations = 0;
+ while (b != e) {
+ int r = __sm_ll_dec(ll, b, e, nr_allocations, &b);
+
+ if (r)
+ return r;
+ }
+
+ return 0;
+}
+
+/*----------------------------------------------------------------*/
+
+int sm_ll_commit(struct ll_disk *ll)
+{
+ int r = 0;
+
+ if (ll->bitmap_index_changed) {
+ r = ll->commit(ll);
+ if (!r)
+ ll->bitmap_index_changed = false;
+ }
+
+ return r;
+}
+
+/*----------------------------------------------------------------*/
+
+static int metadata_ll_load_ie(struct ll_disk *ll, dm_block_t index,
+ struct disk_index_entry *ie)
+{
+ memcpy(ie, ll->mi_le.index + index, sizeof(*ie));
+ return 0;
+}
+
+static int metadata_ll_save_ie(struct ll_disk *ll, dm_block_t index,
+ struct disk_index_entry *ie)
+{
+ ll->bitmap_index_changed = true;
+ memcpy(ll->mi_le.index + index, ie, sizeof(*ie));
+ return 0;
+}
+
+static int metadata_ll_init_index(struct ll_disk *ll)
+{
+ int r;
+ struct dm_block *b;
+
+ r = dm_tm_new_block(ll->tm, &index_validator, &b);
+ if (r < 0)
+ return r;
+
+ ll->bitmap_root = dm_block_location(b);
+
+ dm_tm_unlock(ll->tm, b);
+
+ return 0;
+}
+
+static int metadata_ll_open(struct ll_disk *ll)
+{
+ int r;
+ struct dm_block *block;
+
+ r = dm_tm_read_lock(ll->tm, ll->bitmap_root,
+ &index_validator, &block);
+ if (r)
+ return r;
+
+ memcpy(&ll->mi_le, dm_block_data(block), sizeof(ll->mi_le));
+ dm_tm_unlock(ll->tm, block);
+
+ return 0;
+}
+
+static dm_block_t metadata_ll_max_entries(struct ll_disk *ll)
+{
+ return MAX_METADATA_BITMAPS;
+}
+
+static int metadata_ll_commit(struct ll_disk *ll)
+{
+ int r, inc;
+ struct dm_block *b;
+
+ r = dm_tm_shadow_block(ll->tm, ll->bitmap_root, &index_validator, &b, &inc);
+ if (r)
+ return r;
+
+ memcpy(dm_block_data(b), &ll->mi_le, sizeof(ll->mi_le));
+ ll->bitmap_root = dm_block_location(b);
+
+ dm_tm_unlock(ll->tm, b);
+
+ return 0;
+}
+
+int sm_ll_new_metadata(struct ll_disk *ll, struct dm_transaction_manager *tm)
+{
+ int r;
+
+ r = sm_ll_init(ll, tm);
+ if (r < 0)
+ return r;
+
+ ll->load_ie = metadata_ll_load_ie;
+ ll->save_ie = metadata_ll_save_ie;
+ ll->init_index = metadata_ll_init_index;
+ ll->open_index = metadata_ll_open;
+ ll->max_entries = metadata_ll_max_entries;
+ ll->commit = metadata_ll_commit;
+
+ ll->nr_blocks = 0;
+ ll->nr_allocated = 0;
+
+ r = ll->init_index(ll);
+ if (r < 0)
+ return r;
+
+ r = dm_btree_empty(&ll->ref_count_info, &ll->ref_count_root);
+ if (r < 0)
+ return r;
+
+ return 0;
+}
+
+int sm_ll_open_metadata(struct ll_disk *ll, struct dm_transaction_manager *tm,
+ void *root_le, size_t len)
+{
+ int r;
+ struct disk_sm_root smr;
+
+ if (len < sizeof(struct disk_sm_root)) {
+ DMERR("sm_metadata root too small");
+ return -ENOMEM;
+ }
+
+ /*
+ * We don't know the alignment of the root_le buffer, so need to
+ * copy into a new structure.
+ */
+ memcpy(&smr, root_le, sizeof(smr));
+
+ r = sm_ll_init(ll, tm);
+ if (r < 0)
+ return r;
+
+ ll->load_ie = metadata_ll_load_ie;
+ ll->save_ie = metadata_ll_save_ie;
+ ll->init_index = metadata_ll_init_index;
+ ll->open_index = metadata_ll_open;
+ ll->max_entries = metadata_ll_max_entries;
+ ll->commit = metadata_ll_commit;
+
+ ll->nr_blocks = le64_to_cpu(smr.nr_blocks);
+ ll->nr_allocated = le64_to_cpu(smr.nr_allocated);
+ ll->bitmap_root = le64_to_cpu(smr.bitmap_root);
+ ll->ref_count_root = le64_to_cpu(smr.ref_count_root);
+
+ return ll->open_index(ll);
+}
+
+/*----------------------------------------------------------------*/
+
+static inline int ie_cache_writeback(struct ll_disk *ll, struct ie_cache *iec)
+{
+ iec->dirty = false;
+ __dm_bless_for_disk(iec->ie);
+ return dm_btree_insert(&ll->bitmap_info, ll->bitmap_root,
+ &iec->index, &iec->ie, &ll->bitmap_root);
+}
+
+static inline unsigned int hash_index(dm_block_t index)
+{
+ return dm_hash_block(index, IE_CACHE_MASK);
+}
+
+static int disk_ll_load_ie(struct ll_disk *ll, dm_block_t index,
+ struct disk_index_entry *ie)
+{
+ int r;
+ unsigned int h = hash_index(index);
+ struct ie_cache *iec = ll->ie_cache + h;
+
+ if (iec->valid) {
+ if (iec->index == index) {
+ memcpy(ie, &iec->ie, sizeof(*ie));
+ return 0;
+ }
+
+ if (iec->dirty) {
+ r = ie_cache_writeback(ll, iec);
+ if (r)
+ return r;
+ }
+ }
+
+ r = dm_btree_lookup(&ll->bitmap_info, ll->bitmap_root, &index, ie);
+ if (!r) {
+ iec->valid = true;
+ iec->dirty = false;
+ iec->index = index;
+ memcpy(&iec->ie, ie, sizeof(*ie));
+ }
+
+ return r;
+}
+
+static int disk_ll_save_ie(struct ll_disk *ll, dm_block_t index,
+ struct disk_index_entry *ie)
+{
+ int r;
+ unsigned int h = hash_index(index);
+ struct ie_cache *iec = ll->ie_cache + h;
+
+ ll->bitmap_index_changed = true;
+ if (iec->valid) {
+ if (iec->index == index) {
+ memcpy(&iec->ie, ie, sizeof(*ie));
+ iec->dirty = true;
+ return 0;
+ }
+
+ if (iec->dirty) {
+ r = ie_cache_writeback(ll, iec);
+ if (r)
+ return r;
+ }
+ }
+
+ iec->valid = true;
+ iec->dirty = true;
+ iec->index = index;
+ memcpy(&iec->ie, ie, sizeof(*ie));
+ return 0;
+}
+
+static int disk_ll_init_index(struct ll_disk *ll)
+{
+ unsigned int i;
+
+ for (i = 0; i < IE_CACHE_SIZE; i++) {
+ struct ie_cache *iec = ll->ie_cache + i;
+
+ iec->valid = false;
+ iec->dirty = false;
+ }
+ return dm_btree_empty(&ll->bitmap_info, &ll->bitmap_root);
+}
+
+static int disk_ll_open(struct ll_disk *ll)
+{
+ return 0;
+}
+
+static dm_block_t disk_ll_max_entries(struct ll_disk *ll)
+{
+ return -1ULL;
+}
+
+static int disk_ll_commit(struct ll_disk *ll)
+{
+ int r = 0;
+ unsigned int i;
+
+ for (i = 0; i < IE_CACHE_SIZE; i++) {
+ struct ie_cache *iec = ll->ie_cache + i;
+
+ if (iec->valid && iec->dirty)
+ r = ie_cache_writeback(ll, iec);
+ }
+
+ return r;
+}
+
+int sm_ll_new_disk(struct ll_disk *ll, struct dm_transaction_manager *tm)
+{
+ int r;
+
+ r = sm_ll_init(ll, tm);
+ if (r < 0)
+ return r;
+
+ ll->load_ie = disk_ll_load_ie;
+ ll->save_ie = disk_ll_save_ie;
+ ll->init_index = disk_ll_init_index;
+ ll->open_index = disk_ll_open;
+ ll->max_entries = disk_ll_max_entries;
+ ll->commit = disk_ll_commit;
+
+ ll->nr_blocks = 0;
+ ll->nr_allocated = 0;
+
+ r = ll->init_index(ll);
+ if (r < 0)
+ return r;
+
+ r = dm_btree_empty(&ll->ref_count_info, &ll->ref_count_root);
+ if (r < 0)
+ return r;
+
+ return 0;
+}
+
+int sm_ll_open_disk(struct ll_disk *ll, struct dm_transaction_manager *tm,
+ void *root_le, size_t len)
+{
+ int r;
+ struct disk_sm_root *smr = root_le;
+
+ if (len < sizeof(struct disk_sm_root)) {
+ DMERR("sm_metadata root too small");
+ return -ENOMEM;
+ }
+
+ r = sm_ll_init(ll, tm);
+ if (r < 0)
+ return r;
+
+ ll->load_ie = disk_ll_load_ie;
+ ll->save_ie = disk_ll_save_ie;
+ ll->init_index = disk_ll_init_index;
+ ll->open_index = disk_ll_open;
+ ll->max_entries = disk_ll_max_entries;
+ ll->commit = disk_ll_commit;
+
+ ll->nr_blocks = le64_to_cpu(smr->nr_blocks);
+ ll->nr_allocated = le64_to_cpu(smr->nr_allocated);
+ ll->bitmap_root = le64_to_cpu(smr->bitmap_root);
+ ll->ref_count_root = le64_to_cpu(smr->ref_count_root);
+
+ return ll->open_index(ll);
+}
+
+/*----------------------------------------------------------------*/
generated by cgit v1.2.3 (git 2.39.1) at 2024-08-14 18:48:23 +0000