linux/drivers/misc/ocxl/pasid.c

108 lines
2.1 KiB
C

// SPDX-License-Identifier: GPL-2.0+
// Copyright 2017 IBM Corp.
#include "ocxl_internal.h"
struct id_range {
struct list_head list;
u32 start;
u32 end;
};
#ifdef DEBUG
static void dump_list(struct list_head *head, char *type_str)
{
struct id_range *cur;
pr_debug("%s ranges allocated:\n", type_str);
list_for_each_entry(cur, head, list) {
pr_debug("Range %d->%d\n", cur->start, cur->end);
}
}
#endif
static int range_alloc(struct list_head *head, u32 size, int max_id,
char *type_str)
{
struct list_head *pos;
struct id_range *cur, *new;
int rc, last_end;
new = kmalloc(sizeof(struct id_range), GFP_KERNEL);
if (!new)
return -ENOMEM;
pos = head;
last_end = -1;
list_for_each_entry(cur, head, list) {
if ((cur->start - last_end) > size)
break;
last_end = cur->end;
pos = &cur->list;
}
new->start = last_end + 1;
new->end = new->start + size - 1;
if (new->end > max_id) {
kfree(new);
rc = -ENOSPC;
} else {
list_add(&new->list, pos);
rc = new->start;
}
#ifdef DEBUG
dump_list(head, type_str);
#endif
return rc;
}
static void range_free(struct list_head *head, u32 start, u32 size,
char *type_str)
{
bool found = false;
struct id_range *cur, *tmp;
list_for_each_entry_safe(cur, tmp, head, list) {
if (cur->start == start && cur->end == (start + size - 1)) {
found = true;
list_del(&cur->list);
kfree(cur);
break;
}
}
WARN_ON(!found);
#ifdef DEBUG
dump_list(head, type_str);
#endif
}
int ocxl_pasid_afu_alloc(struct ocxl_fn *fn, u32 size)
{
int max_pasid;
if (fn->config.max_pasid_log < 0)
return -ENOSPC;
max_pasid = 1 << fn->config.max_pasid_log;
return range_alloc(&fn->pasid_list, size, max_pasid, "afu pasid");
}
void ocxl_pasid_afu_free(struct ocxl_fn *fn, u32 start, u32 size)
{
return range_free(&fn->pasid_list, start, size, "afu pasid");
}
int ocxl_actag_afu_alloc(struct ocxl_fn *fn, u32 size)
{
int max_actag;
max_actag = fn->actag_enabled;
return range_alloc(&fn->actag_list, size, max_actag, "afu actag");
}
void ocxl_actag_afu_free(struct ocxl_fn *fn, u32 start, u32 size)
{
return range_free(&fn->actag_list, start, size, "afu actag");
}