/*
* 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("index_check failed: blocknr %llu != wanted %llu",
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("index_check failed: csum %u != wanted %u",
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);
} else {
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);
}
/*----------------------------------------------------------------*/
