Orange Pi5 kernel

^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  1) // SPDX-License-Identifier: GPL-2.0
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  2) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  3)  * Simple pointer stack
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  4)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  5)  * (c) 2010 Arnaldo Carvalho de Melo <acme@redhat.com>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  6)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  7) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  8) #include "pstack.h"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  9) #include "debug.h"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10) #include <linux/kernel.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11) #include <linux/zalloc.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12) #include <stdlib.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13) #include <string.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15) struct pstack {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16) 	unsigned short	top;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17) 	unsigned short	max_nr_entries;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18) 	void		*entries[];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21) struct pstack *pstack__new(unsigned short max_nr_entries)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23) 	struct pstack *pstack = zalloc((sizeof(*pstack) +
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24) 				       max_nr_entries * sizeof(void *)));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25) 	if (pstack != NULL)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26) 		pstack->max_nr_entries = max_nr_entries;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27) 	return pstack;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30) void pstack__delete(struct pstack *pstack)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32) 	free(pstack);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35) bool pstack__empty(const struct pstack *pstack)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37) 	return pstack->top == 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40) void pstack__remove(struct pstack *pstack, void *key)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42) 	unsigned short i = pstack->top, last_index = pstack->top - 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44) 	while (i-- != 0) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45) 		if (pstack->entries[i] == key) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46) 			if (i < last_index)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47) 				memmove(pstack->entries + i,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48) 					pstack->entries + i + 1,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49) 					(last_index - i) * sizeof(void *));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50) 			--pstack->top;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51) 			return;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52) 		}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54) 	pr_err("%s: %p not on the pstack!\n", __func__, key);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57) void pstack__push(struct pstack *pstack, void *key)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59) 	if (pstack->top == pstack->max_nr_entries) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60) 		pr_err("%s: top=%d, overflow!\n", __func__, pstack->top);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61) 		return;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63) 	pstack->entries[pstack->top++] = key;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 64) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 65) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 66) void *pstack__pop(struct pstack *pstack)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 67) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 68) 	void *ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 69) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 70) 	if (pstack->top == 0) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 71) 		pr_err("%s: underflow!\n", __func__);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 72) 		return NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 73) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 74) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 75) 	ret = pstack->entries[--pstack->top];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 76) 	pstack->entries[pstack->top] = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 77) 	return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 78) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 79) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 80) void *pstack__peek(struct pstack *pstack)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 81) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 82) 	if (pstack->top == 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 83) 		return NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 84) 	return pstack->entries[pstack->top - 1];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 85) }