Author | Tokens | Token Proportion | Commits | Commit Proportion |
---|---|---|---|---|
Mark A. Greer | 550 | 94.18% | 1 | 33.33% |
Geert Uytterhoeven | 32 | 5.48% | 1 | 33.33% |
Michael Ellerman | 2 | 0.34% | 1 | 33.33% |
Total | 584 | 3 |
// SPDX-License-Identifier: GPL-2.0 /* * Implement primitive realloc(3) functionality. * * Author: Mark A. Greer <mgreer@mvista.com> * * 2006 (c) MontaVista, Software, Inc. */ #include <stddef.h> #include "types.h" #include "page.h" #include "string.h" #include "ops.h" #define ENTRY_BEEN_USED 0x01 #define ENTRY_IN_USE 0x02 static struct alloc_info { unsigned long flags; unsigned long base; unsigned long size; } *alloc_tbl; static unsigned long tbl_entries; static unsigned long alloc_min; static unsigned long next_base; static unsigned long space_left; /* * First time an entry is used, its base and size are set. * An entry can be freed and re-malloc'd but its base & size don't change. * Should be smart enough for needs of bootwrapper. */ static void *simple_malloc(unsigned long size) { unsigned long i; struct alloc_info *p = alloc_tbl; if (size == 0) goto err_out; size = _ALIGN_UP(size, alloc_min); for (i=0; i<tbl_entries; i++, p++) if (!(p->flags & ENTRY_BEEN_USED)) { /* never been used */ if (size <= space_left) { p->base = next_base; p->size = size; p->flags = ENTRY_BEEN_USED | ENTRY_IN_USE; next_base += size; space_left -= size; return (void *)p->base; } goto err_out; /* not enough space left */ } /* reuse an entry keeping same base & size */ else if (!(p->flags & ENTRY_IN_USE) && (size <= p->size)) { p->flags |= ENTRY_IN_USE; return (void *)p->base; } err_out: return NULL; } static struct alloc_info *simple_find_entry(void *ptr) { unsigned long i; struct alloc_info *p = alloc_tbl; for (i=0; i<tbl_entries; i++,p++) { if (!(p->flags & ENTRY_BEEN_USED)) break; if ((p->flags & ENTRY_IN_USE) && (p->base == (unsigned long)ptr)) return p; } return NULL; } static void simple_free(void *ptr) { struct alloc_info *p = simple_find_entry(ptr); if (p != NULL) p->flags &= ~ENTRY_IN_USE; } /* * Change size of area pointed to by 'ptr' to 'size'. * If 'ptr' is NULL, then its a malloc(). If 'size' is 0, then its a free(). * 'ptr' must be NULL or a pointer to a non-freed area previously returned by * simple_realloc() or simple_malloc(). */ static void *simple_realloc(void *ptr, unsigned long size) { struct alloc_info *p; void *new; if (size == 0) { simple_free(ptr); return NULL; } if (ptr == NULL) return simple_malloc(size); p = simple_find_entry(ptr); if (p == NULL) /* ptr not from simple_malloc/simple_realloc */ return NULL; if (size <= p->size) /* fits in current block */ return ptr; new = simple_malloc(size); memcpy(new, ptr, p->size); simple_free(ptr); return new; } /* * Returns addr of first byte after heap so caller can see if it took * too much space. If so, change args & try again. */ void *simple_alloc_init(char *base, unsigned long heap_size, unsigned long granularity, unsigned long max_allocs) { unsigned long heap_base, tbl_size; heap_size = _ALIGN_UP(heap_size, granularity); alloc_min = granularity; tbl_entries = max_allocs; tbl_size = tbl_entries * sizeof(struct alloc_info); alloc_tbl = (struct alloc_info *)_ALIGN_UP((unsigned long)base, 8); memset(alloc_tbl, 0, tbl_size); heap_base = _ALIGN_UP((unsigned long)alloc_tbl + tbl_size, alloc_min); next_base = heap_base; space_left = heap_size; platform_ops.malloc = simple_malloc; platform_ops.free = simple_free; platform_ops.realloc = simple_realloc; return (void *)(heap_base + heap_size); }
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