static int scan_free(struct nd_region *nd_region,
struct nd_mapping *nd_mapping, struct nd_label_id *label_id,
resource_size_t n)
{
bool is_blk = strncmp(label_id->id, "blk", 3) == 0;
struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
int rc = 0;
while (n) {
struct resource *res, *last;
resource_size_t new_start;
last = NULL;
for_each_dpa_resource(ndd, res)
if (strcmp(res->name, label_id->id) == 0)
last = res;
res = last;
if (!res)
return 0;
if (n >= resource_size(res)) {
n -= resource_size(res);
nd_dbg_dpa(nd_region, ndd, res, "delete %d\n", rc);
nvdimm_free_dpa(ndd, res);
/* retry with last resource deleted */
continue;
}
/*
* Keep BLK allocations relegated to high DPA as much as
* possible
*/
if (is_blk)
new_start = res->start + n;
else
new_start = res->start;
rc = adjust_resource(res, new_start, resource_size(res) - n);
if (rc == 0)
res->flags |= DPA_RESOURCE_ADJUSTED;
nd_dbg_dpa(nd_region, ndd, res, "shrink %d\n", rc);
break;
}
return rc;
}
static resource_size_t init_dpa_allocation(struct nd_label_id *label_id,
struct nd_region *nd_region, struct nd_mapping *nd_mapping,
resource_size_t n)
{
bool is_blk = strncmp(label_id->id, "blk", 3) == 0;
struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
resource_size_t first_dpa;
struct resource *res;
int rc = 0;
/* allocate blk from highest dpa first */
if (is_blk)
first_dpa = nd_mapping->start + nd_mapping->size - n;
else
first_dpa = nd_mapping->start;
/* first resource allocation for this label-id or dimm */
res = nvdimm_allocate_dpa(ndd, label_id, first_dpa, n);
if (!res)
rc = -EBUSY;
nd_dbg_dpa(nd_region, ndd, res, "init %d\n", rc);
return rc ? n : 0;
}
/**
* nd_pmem_available_dpa - for the given dimm+region account unallocated dpa
* @nd_mapping: container of dpa-resource-root + labels
* @nd_region: constrain available space check to this reference region
* @overlap: calculate available space assuming this level of overlap
*
* Validate that a PMEM label, if present, aligns with the start of an
* interleave set and truncate the available size at the lowest BLK
* overlap point.
*
* The expectation is that this routine is called multiple times as it
* probes for the largest BLK encroachment for any single member DIMM of
* the interleave set. Once that value is determined the PMEM-limit for
* the set can be established.
*/
resource_size_t nd_pmem_available_dpa(struct nd_region *nd_region,
struct nd_mapping *nd_mapping, resource_size_t *overlap)
{
resource_size_t map_start, map_end, busy = 0, available, blk_start;
struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
struct resource *res;
const char *reason;
if (!ndd)
return 0;
map_start = nd_mapping->start;
map_end = map_start + nd_mapping->size - 1;
blk_start = max(map_start, map_end + 1 - *overlap);
for_each_dpa_resource(ndd, res)
if (res->start >= map_start && res->start < map_end) {
if (strncmp(res->name, "blk", 3) == 0)
blk_start = min(blk_start, res->start);
else if (res->start != map_start) {
reason = "misaligned to iset";
goto err;
} else {
if (busy) {
reason = "duplicate overlapping PMEM reservations?";
goto err;
}
busy += resource_size(res);
continue;
}
} else if (res->end >= map_start && res->end <= map_end) {
if (strncmp(res->name, "blk", 3) == 0) {
/*
* If a BLK allocation overlaps the start of
* PMEM the entire interleave set may now only
* be used for BLK.
*/
blk_start = map_start;
} else {
reason = "misaligned to iset";
goto err;
}
} else if (map_start > res->start && map_start < res->end) {
/* total eclipse of the mapping */
busy += nd_mapping->size;
blk_start = map_start;
}
*overlap = map_end + 1 - blk_start;
available = blk_start - map_start;
if (busy < available)
return available - busy;
return 0;
err:
/*
* Something is wrong, PMEM must align with the start of the
* interleave set, and there can only be one allocation per set.
*/
nd_dbg_dpa(nd_region, ndd, res, "%s\n", reason);
return 0;
}
static resource_size_t scan_allocate(struct nd_region *nd_region,
struct nd_mapping *nd_mapping, struct nd_label_id *label_id,
resource_size_t n)
{
resource_size_t mapping_end = nd_mapping->start + nd_mapping->size - 1;
bool is_reserve = strcmp(label_id->id, "pmem-reserve") == 0;
bool is_pmem = strncmp(label_id->id, "pmem", 4) == 0;
struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
const resource_size_t to_allocate = n;
struct resource *res;
int first;
retry:
first = 0;
for_each_dpa_resource(ndd, res) {
resource_size_t allocate, available = 0, free_start, free_end;
struct resource *next = res->sibling, *new_res = NULL;
enum alloc_loc loc = ALLOC_ERR;
const char *action;
int rc = 0;
/* ignore resources outside this nd_mapping */
if (res->start > mapping_end)
continue;
if (res->end < nd_mapping->start)
continue;
/* space at the beginning of the mapping */
if (!first++ && res->start > nd_mapping->start) {
free_start = nd_mapping->start;
available = res->start - free_start;
if (space_valid(is_pmem, is_reserve, label_id, NULL))
loc = ALLOC_BEFORE;
}
/* space between allocations */
if (!loc && next) {
free_start = res->start + resource_size(res);
free_end = min(mapping_end, next->start - 1);
if (space_valid(is_pmem, is_reserve, label_id, res)
&& free_start < free_end) {
available = free_end + 1 - free_start;
loc = ALLOC_MID;
}
}
/* space at the end of the mapping */
if (!loc && !next) {
free_start = res->start + resource_size(res);
free_end = mapping_end;
if (space_valid(is_pmem, is_reserve, label_id, res)
&& free_start < free_end) {
available = free_end + 1 - free_start;
loc = ALLOC_AFTER;
}
}
if (!loc || !available)
continue;
allocate = min(available, n);
switch (loc) {
case ALLOC_BEFORE:
if (strcmp(res->name, label_id->id) == 0) {
/* adjust current resource up */
if (is_pmem && !is_reserve)
return n;
rc = adjust_resource(res, res->start - allocate,
resource_size(res) + allocate);
action = "cur grow up";
} else
action = "allocate";
break;
case ALLOC_MID:
if (strcmp(next->name, label_id->id) == 0) {
/* adjust next resource up */
if (is_pmem && !is_reserve)
return n;
rc = adjust_resource(next, next->start
- allocate, resource_size(next)
+ allocate);
new_res = next;
action = "next grow up";
} else if (strcmp(res->name, label_id->id) == 0) {
action = "grow down";
} else
action = "allocate";
break;
case ALLOC_AFTER:
if (strcmp(res->name, label_id->id) == 0)
action = "grow down";
else
action = "allocate";
break;
default:
return n;
}
if (strcmp(action, "allocate") == 0) {
/* BLK allocate bottom up */
if (!is_pmem)
free_start += available - allocate;
else if (!is_reserve && free_start != nd_mapping->start)
return n;
new_res = nvdimm_allocate_dpa(ndd, label_id,
free_start, allocate);
if (!new_res)
rc = -EBUSY;
} else if (strcmp(action, "grow down") == 0) {
/* adjust current resource down */
rc = adjust_resource(res, res->start, resource_size(res)
+ allocate);
if (rc == 0)
res->flags |= DPA_RESOURCE_ADJUSTED;
}
if (!new_res)
new_res = res;
nd_dbg_dpa(nd_region, ndd, new_res, "%s(%d) %d\n",
action, loc, rc);
if (rc)
return n;
n -= allocate;
if (n) {
/*
* Retry scan with newly inserted resources.
* For example, if we did an ALLOC_BEFORE
* insertion there may also have been space
* available for an ALLOC_AFTER insertion, so we
* need to check this same resource again
*/
goto retry;
} else
return 0;
}
