dm btree remove: change a bunch of BUG_ON() calls to proper errors
Abuse of BUG_ON() is never appropriate, best to propagate errors to fail gracefully (rather than take the entire system down). Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
This commit is contained in:
Joe Thornber
Mike Snitzer
parent
e36649b648
commit
c671ffa55d
|
|
@ -9,6 +9,9 @@
|
|||
#include "dm-transaction-manager.h"
|
||||
|
||||
#include <linux/export.h>
|
||||
#include <linux/device-mapper.h>
|
||||
|
||||
#define DM_MSG_PREFIX "btree"
|
||||
|
||||
/*
|
||||
* Removing an entry from a btree
|
||||
|
|
@ -79,15 +82,23 @@ static void node_shift(struct btree_node *n, int shift)
|
|||
}
|
||||
}
|
||||
|
||||
static void node_copy(struct btree_node *left, struct btree_node *right, int shift)
|
||||
static int node_copy(struct btree_node *left, struct btree_node *right, int shift)
|
||||
{
|
||||
uint32_t nr_left = le32_to_cpu(left->header.nr_entries);
|
||||
uint32_t value_size = le32_to_cpu(left->header.value_size);
|
||||
BUG_ON(value_size != le32_to_cpu(right->header.value_size));
|
||||
if (value_size != le32_to_cpu(right->header.value_size)) {
|
||||
DMERR("mismatched value size");
|
||||
return -EILSEQ;
|
||||
}
|
||||
|
||||
if (shift < 0) {
|
||||
shift = -shift;
|
||||
BUG_ON(nr_left + shift > le32_to_cpu(left->header.max_entries));
|
||||
|
||||
if (nr_left + shift > le32_to_cpu(left->header.max_entries)) {
|
||||
DMERR("bad shift");
|
||||
return -EINVAL;
|
||||
}
|
||||
|
||||
memcpy(key_ptr(left, nr_left),
|
||||
key_ptr(right, 0),
|
||||
shift * sizeof(__le64));
|
||||
|
|
@ -95,7 +106,11 @@ static void node_copy(struct btree_node *left, struct btree_node *right, int shi
|
|||
value_ptr(right, 0),
|
||||
shift * value_size);
|
||||
} else {
|
||||
BUG_ON(shift > le32_to_cpu(right->header.max_entries));
|
||||
if (shift > le32_to_cpu(right->header.max_entries)) {
|
||||
DMERR("bad shift");
|
||||
return -EINVAL;
|
||||
}
|
||||
|
||||
memcpy(key_ptr(right, 0),
|
||||
key_ptr(left, nr_left - shift),
|
||||
shift * sizeof(__le64));
|
||||
|
|
@ -103,6 +118,7 @@ static void node_copy(struct btree_node *left, struct btree_node *right, int shi
|
|||
value_ptr(left, nr_left - shift),
|
||||
shift * value_size);
|
||||
}
|
||||
return 0;
|
||||
}
|
||||
|
||||
/*
|
||||
|
|
@ -170,35 +186,54 @@ static void exit_child(struct dm_btree_info *info, struct child *c)
|
|||
dm_tm_unlock(info->tm, c->block);
|
||||
}
|
||||
|
||||
static void shift(struct btree_node *left, struct btree_node *right, int count)
|
||||
static int shift(struct btree_node *left, struct btree_node *right, int count)
|
||||
{
|
||||
int r;
|
||||
uint32_t nr_left = le32_to_cpu(left->header.nr_entries);
|
||||
uint32_t nr_right = le32_to_cpu(right->header.nr_entries);
|
||||
uint32_t max_entries = le32_to_cpu(left->header.max_entries);
|
||||
uint32_t r_max_entries = le32_to_cpu(right->header.max_entries);
|
||||
|
||||
BUG_ON(max_entries != r_max_entries);
|
||||
BUG_ON(nr_left - count > max_entries);
|
||||
BUG_ON(nr_right + count > max_entries);
|
||||
if (max_entries != r_max_entries) {
|
||||
DMERR("node max_entries mismatch");
|
||||
return -EILSEQ;
|
||||
}
|
||||
|
||||
if (nr_left - count > max_entries) {
|
||||
DMERR("node shift out of bounds");
|
||||
return -EINVAL;
|
||||
}
|
||||
|
||||
if (nr_right + count > max_entries) {
|
||||
DMERR("node shift out of bounds");
|
||||
return -EINVAL;
|
||||
}
|
||||
|
||||
if (!count)
|
||||
return;
|
||||
return 0;
|
||||
|
||||
if (count > 0) {
|
||||
node_shift(right, count);
|
||||
node_copy(left, right, count);
|
||||
r = node_copy(left, right, count);
|
||||
if (r)
|
||||
return r;
|
||||
} else {
|
||||
node_copy(left, right, count);
|
||||
r = node_copy(left, right, count);
|
||||
if (r)
|
||||
return r;
|
||||
node_shift(right, count);
|
||||
}
|
||||
|
||||
left->header.nr_entries = cpu_to_le32(nr_left - count);
|
||||
right->header.nr_entries = cpu_to_le32(nr_right + count);
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static void __rebalance2(struct dm_btree_info *info, struct btree_node *parent,
|
||||
struct child *l, struct child *r)
|
||||
static int __rebalance2(struct dm_btree_info *info, struct btree_node *parent,
|
||||
struct child *l, struct child *r)
|
||||
{
|
||||
int ret;
|
||||
struct btree_node *left = l->n;
|
||||
struct btree_node *right = r->n;
|
||||
uint32_t nr_left = le32_to_cpu(left->header.nr_entries);
|
||||
|
|
@ -229,9 +264,12 @@ static void __rebalance2(struct dm_btree_info *info, struct btree_node *parent,
|
|||
* Rebalance.
|
||||
*/
|
||||
unsigned target_left = (nr_left + nr_right) / 2;
|
||||
shift(left, right, nr_left - target_left);
|
||||
ret = shift(left, right, nr_left - target_left);
|
||||
if (ret)
|
||||
return ret;
|
||||
*key_ptr(parent, r->index) = right->keys[0];
|
||||
}
|
||||
return 0;
|
||||
}
|
||||
|
||||
static int rebalance2(struct shadow_spine *s, struct dm_btree_info *info,
|
||||
|
|
@ -253,12 +291,12 @@ static int rebalance2(struct shadow_spine *s, struct dm_btree_info *info,
|
|||
return r;
|
||||
}
|
||||
|
||||
__rebalance2(info, parent, &left, &right);
|
||||
r = __rebalance2(info, parent, &left, &right);
|
||||
|
||||
exit_child(info, &left);
|
||||
exit_child(info, &right);
|
||||
|
||||
return 0;
|
||||
return r;
|
||||
}
|
||||
|
||||
/*
|
||||
|
|
@ -266,21 +304,30 @@ static int rebalance2(struct shadow_spine *s, struct dm_btree_info *info,
|
|||
* in right, then rebalance2. This wastes some cpu, but I want something
|
||||
* simple atm.
|
||||
*/
|
||||
static void delete_center_node(struct dm_btree_info *info, struct btree_node *parent,
|
||||
struct child *l, struct child *c, struct child *r,
|
||||
struct btree_node *left, struct btree_node *center, struct btree_node *right,
|
||||
uint32_t nr_left, uint32_t nr_center, uint32_t nr_right)
|
||||
static int delete_center_node(struct dm_btree_info *info, struct btree_node *parent,
|
||||
struct child *l, struct child *c, struct child *r,
|
||||
struct btree_node *left, struct btree_node *center, struct btree_node *right,
|
||||
uint32_t nr_left, uint32_t nr_center, uint32_t nr_right)
|
||||
{
|
||||
uint32_t max_entries = le32_to_cpu(left->header.max_entries);
|
||||
unsigned shift = min(max_entries - nr_left, nr_center);
|
||||
|
||||
BUG_ON(nr_left + shift > max_entries);
|
||||
if (nr_left + shift > max_entries) {
|
||||
DMERR("node shift out of bounds");
|
||||
return -EINVAL;
|
||||
}
|
||||
|
||||
node_copy(left, center, -shift);
|
||||
left->header.nr_entries = cpu_to_le32(nr_left + shift);
|
||||
|
||||
if (shift != nr_center) {
|
||||
shift = nr_center - shift;
|
||||
BUG_ON((nr_right + shift) > max_entries);
|
||||
|
||||
if ((nr_right + shift) > max_entries) {
|
||||
DMERR("node shift out of bounds");
|
||||
return -EINVAL;
|
||||
}
|
||||
|
||||
node_shift(right, shift);
|
||||
node_copy(center, right, shift);
|
||||
right->header.nr_entries = cpu_to_le32(nr_right + shift);
|
||||
|
|
@ -291,18 +338,18 @@ static void delete_center_node(struct dm_btree_info *info, struct btree_node *pa
|
|||
r->index--;
|
||||
|
||||
dm_tm_dec(info->tm, dm_block_location(c->block));
|
||||
__rebalance2(info, parent, l, r);
|
||||
return __rebalance2(info, parent, l, r);
|
||||
}
|
||||
|
||||
/*
|
||||
* Redistributes entries among 3 sibling nodes.
|
||||
*/
|
||||
static void redistribute3(struct dm_btree_info *info, struct btree_node *parent,
|
||||
struct child *l, struct child *c, struct child *r,
|
||||
struct btree_node *left, struct btree_node *center, struct btree_node *right,
|
||||
uint32_t nr_left, uint32_t nr_center, uint32_t nr_right)
|
||||
static int redistribute3(struct dm_btree_info *info, struct btree_node *parent,
|
||||
struct child *l, struct child *c, struct child *r,
|
||||
struct btree_node *left, struct btree_node *center, struct btree_node *right,
|
||||
uint32_t nr_left, uint32_t nr_center, uint32_t nr_right)
|
||||
{
|
||||
int s;
|
||||
int s, ret;
|
||||
uint32_t max_entries = le32_to_cpu(left->header.max_entries);
|
||||
unsigned total = nr_left + nr_center + nr_right;
|
||||
unsigned target_right = total / 3;
|
||||
|
|
@ -317,35 +364,55 @@ static void redistribute3(struct dm_btree_info *info, struct btree_node *parent,
|
|||
|
||||
if (s < 0 && nr_center < -s) {
|
||||
/* not enough in central node */
|
||||
shift(left, center, -nr_center);
|
||||
ret = shift(left, center, -nr_center);
|
||||
if (ret)
|
||||
return ret;
|
||||
|
||||
s += nr_center;
|
||||
shift(left, right, s);
|
||||
ret = shift(left, right, s);
|
||||
if (ret)
|
||||
return ret;
|
||||
|
||||
nr_right += s;
|
||||
} else
|
||||
shift(left, center, s);
|
||||
|
||||
shift(center, right, target_right - nr_right);
|
||||
} else {
|
||||
ret = shift(left, center, s);
|
||||
if (ret)
|
||||
return ret;
|
||||
}
|
||||
|
||||
ret = shift(center, right, target_right - nr_right);
|
||||
if (ret)
|
||||
return ret;
|
||||
} else {
|
||||
s = target_right - nr_right;
|
||||
if (s > 0 && nr_center < s) {
|
||||
/* not enough in central node */
|
||||
shift(center, right, nr_center);
|
||||
ret = shift(center, right, nr_center);
|
||||
if (ret)
|
||||
return ret;
|
||||
s -= nr_center;
|
||||
shift(left, right, s);
|
||||
ret = shift(left, right, s);
|
||||
if (ret)
|
||||
return ret;
|
||||
nr_left -= s;
|
||||
} else
|
||||
shift(center, right, s);
|
||||
} else {
|
||||
ret = shift(center, right, s);
|
||||
if (ret)
|
||||
return ret;
|
||||
}
|
||||
|
||||
shift(left, center, nr_left - target_left);
|
||||
ret = shift(left, center, nr_left - target_left);
|
||||
if (ret)
|
||||
return ret;
|
||||
}
|
||||
|
||||
*key_ptr(parent, c->index) = center->keys[0];
|
||||
*key_ptr(parent, r->index) = right->keys[0];
|
||||
return 0;
|
||||
}
|
||||
|
||||
static void __rebalance3(struct dm_btree_info *info, struct btree_node *parent,
|
||||
struct child *l, struct child *c, struct child *r)
|
||||
static int __rebalance3(struct dm_btree_info *info, struct btree_node *parent,
|
||||
struct child *l, struct child *c, struct child *r)
|
||||
{
|
||||
struct btree_node *left = l->n;
|
||||
struct btree_node *center = c->n;
|
||||
|
|
@ -357,15 +424,19 @@ static void __rebalance3(struct dm_btree_info *info, struct btree_node *parent,
|
|||
|
||||
unsigned threshold = merge_threshold(left) * 4 + 1;
|
||||
|
||||
BUG_ON(left->header.max_entries != center->header.max_entries);
|
||||
BUG_ON(center->header.max_entries != right->header.max_entries);
|
||||
if ((left->header.max_entries != center->header.max_entries) ||
|
||||
(center->header.max_entries != right->header.max_entries)) {
|
||||
DMERR("bad btree metadata, max_entries differ");
|
||||
return -EILSEQ;
|
||||
}
|
||||
|
||||
if ((nr_left + nr_center + nr_right) < threshold)
|
||||
delete_center_node(info, parent, l, c, r, left, center, right,
|
||||
nr_left, nr_center, nr_right);
|
||||
else
|
||||
redistribute3(info, parent, l, c, r, left, center, right,
|
||||
nr_left, nr_center, nr_right);
|
||||
if ((nr_left + nr_center + nr_right) < threshold) {
|
||||
return delete_center_node(info, parent, l, c, r, left, center, right,
|
||||
nr_left, nr_center, nr_right);
|
||||
}
|
||||
|
||||
return redistribute3(info, parent, l, c, r, left, center, right,
|
||||
nr_left, nr_center, nr_right);
|
||||
}
|
||||
|
||||
static int rebalance3(struct shadow_spine *s, struct dm_btree_info *info,
|
||||
|
|
@ -395,13 +466,13 @@ static int rebalance3(struct shadow_spine *s, struct dm_btree_info *info,
|
|||
return r;
|
||||
}
|
||||
|
||||
__rebalance3(info, parent, &left, ¢er, &right);
|
||||
r = __rebalance3(info, parent, &left, ¢er, &right);
|
||||
|
||||
exit_child(info, &left);
|
||||
exit_child(info, ¢er);
|
||||
exit_child(info, &right);
|
||||
|
||||
return 0;
|
||||
return r;
|
||||
}
|
||||
|
||||
static int rebalance_children(struct shadow_spine *s,
|
||||
|
|
|
|||
Loading…
Reference in New Issue