Index: head/libexec/rtld-elf/rtld_malloc.c =================================================================== --- head/libexec/rtld-elf/rtld_malloc.c (revision 351689) +++ head/libexec/rtld-elf/rtld_malloc.c (revision 351690) @@ -1,320 +1,289 @@ /*- * SPDX-License-Identifier: BSD-3-Clause * * Copyright (c) 1983 Regents of the University of California. * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #if defined(LIBC_SCCS) && !defined(lint) /*static char *sccsid = "from: @(#)malloc.c 5.11 (Berkeley) 2/23/91";*/ static char *rcsid = "$FreeBSD$"; #endif /* LIBC_SCCS and not lint */ /* * malloc.c (Caltech) 2/21/82 * Chris Kingsley, kingsley@cit-20. * * This is a very fast storage allocator. It allocates blocks of a small * number of different sizes, and keeps free lists of each size. Blocks that * don't exactly fit are passed up to the next larger size. In this * implementation, the available sizes are 2^n-4 (or 2^n-10) bytes long. * This is designed for use in a virtual memory environment. */ #include #include #include #include #include #include #include #include #include "rtld.h" #include "rtld_printf.h" #include "paths.h" /* * Pre-allocate mmap'ed pages */ #define NPOOLPAGES (128*1024/pagesz) static caddr_t pagepool_start, pagepool_end; /* * The overhead on a block is at least 4 bytes. When free, this space * contains a pointer to the next free block, and the bottom two bits must * be zero. When in use, the first byte is set to MAGIC, and the second * byte is the size index. The remaining bytes are for alignment. * If range checking is enabled then a second word holds the size of the * requested block, less 1, rounded up to a multiple of sizeof(RMAGIC). * The order of elements is critical: ov_magic must overlay the low order * bits of ov_next, and ov_magic can not be a valid ov_next bit pattern. */ union overhead { union overhead *ov_next; /* when free */ struct { u_char ovu_magic; /* magic number */ u_char ovu_index; /* bucket # */ } ovu; #define ov_magic ovu.ovu_magic #define ov_index ovu.ovu_index }; static void morecore(int bucket); static int morepages(int n); #define MAGIC 0xef /* magic # on accounting info */ /* - * nextf[i] is the pointer to the next free block of size 2^(i+3). The - * smallest allocatable block is 8 bytes. The overhead information - * precedes the data area returned to the user. + * nextf[i] is the pointer to the next free block of size + * (FIRST_BUCKET_SIZE << i). The overhead information precedes the data + * area returned to the user. */ +#define FIRST_BUCKET_SIZE 8 #define NBUCKETS 30 static union overhead *nextf[NBUCKETS]; static int pagesz; /* page size */ -static int pagebucket; /* page size bucket */ /* * The array of supported page sizes is provided by the user, i.e., the * program that calls this storage allocator. That program must initialize * the array before making its first call to allocate storage. The array * must contain at least one page size. The page sizes must be stored in * increasing order. */ void * __crt_malloc(size_t nbytes) { union overhead *op; int bucket; - ssize_t n; size_t amt; /* - * First time malloc is called, setup page size and - * align break pointer so all data will be page aligned. + * First time malloc is called, setup page size. */ - if (pagesz == 0) { - pagesz = n = pagesizes[0]; - if (morepages(NPOOLPAGES) == 0) - return NULL; - op = (union overhead *)(pagepool_start); - n = n - sizeof (*op) - ((long)op & (n - 1)); - if (n < 0) - n += pagesz; - if (n) { - pagepool_start += n; - } - bucket = 0; - amt = 8; - while ((unsigned)pagesz > amt) { - amt <<= 1; - bucket++; - } - pagebucket = bucket; - } + if (pagesz == 0) + pagesz = pagesizes[0]; /* * Convert amount of memory requested into closest block size * stored in hash buckets which satisfies request. * Account for space used per block for accounting. */ - if (nbytes <= (unsigned long)(n = pagesz - sizeof(*op))) { - amt = 8; /* size of first bucket */ - bucket = 0; - n = -sizeof(*op); - } else { - amt = pagesz; - bucket = pagebucket; - } - while (nbytes > amt + n) { + amt = FIRST_BUCKET_SIZE; + bucket = 0; + while (nbytes > amt - sizeof(*op)) { amt <<= 1; - if (amt == 0) - return (NULL); bucket++; + if (amt == 0 || bucket >= NBUCKETS) + return (NULL); } /* * If nothing in hash bucket right now, * request more memory from the system. */ if ((op = nextf[bucket]) == NULL) { morecore(bucket); if ((op = nextf[bucket]) == NULL) return (NULL); } /* remove from linked list */ nextf[bucket] = op->ov_next; op->ov_magic = MAGIC; op->ov_index = bucket; return ((char *)(op + 1)); } void * __crt_calloc(size_t num, size_t size) { void *ret; if (size != 0 && (num * size) / size != num) { /* size_t overflow. */ return (NULL); } if ((ret = __crt_malloc(num * size)) != NULL) memset(ret, 0, num * size); return (ret); } /* * Allocate more memory to the indicated bucket. */ static void morecore(int bucket) { union overhead *op; int sz; /* size of desired block */ int amt; /* amount to allocate */ int nblks; /* how many blocks we get */ - /* - * sbrk_size <= 0 only for big, FLUFFY, requests (about - * 2^30 bytes on a VAX, I think) or for a negative arg. - */ - if ((unsigned)bucket >= NBBY * sizeof(int) - 4) - return; - sz = 1 << (bucket + 3); + sz = FIRST_BUCKET_SIZE << bucket; if (sz < pagesz) { amt = pagesz; nblks = amt / sz; } else { - amt = sz + pagesz; + amt = sz; nblks = 1; } if (amt > pagepool_end - pagepool_start) if (morepages(amt/pagesz + NPOOLPAGES) == 0) return; op = (union overhead *)pagepool_start; pagepool_start += amt; /* * Add new memory allocated to that on * free list for this hash bucket. */ nextf[bucket] = op; while (--nblks > 0) { op->ov_next = (union overhead *)((caddr_t)op + sz); op = (union overhead *)((caddr_t)op + sz); } } void __crt_free(void *cp) { int size; union overhead *op; if (cp == NULL) return; op = (union overhead *)((caddr_t)cp - sizeof (union overhead)); if (op->ov_magic != MAGIC) return; /* sanity */ size = op->ov_index; op->ov_next = nextf[size]; /* also clobbers ov_magic */ nextf[size] = op; } void * __crt_realloc(void *cp, size_t nbytes) { u_int onb; int i; union overhead *op; char *res; if (cp == NULL) return (__crt_malloc(nbytes)); op = (union overhead *)((caddr_t)cp - sizeof (union overhead)); if (op->ov_magic != MAGIC) return (NULL); /* Double-free or bad argument */ i = op->ov_index; onb = 1 << (i + 3); if (onb < (u_int)pagesz) onb -= sizeof(*op); else onb += pagesz - sizeof(*op); /* avoid the copy if same size block */ if (i != 0) { i = 1 << (i + 2); if (i < pagesz) i -= sizeof(*op); else i += pagesz - sizeof(*op); } if (nbytes <= onb && nbytes > (size_t)i) return (cp); if ((res = __crt_malloc(nbytes)) == NULL) return (NULL); bcopy(cp, res, (nbytes < onb) ? nbytes : onb); __crt_free(cp); return (res); } static int morepages(int n) { caddr_t addr; int offset; if (pagepool_end - pagepool_start > pagesz) { addr = (caddr_t)roundup2((long)pagepool_start, pagesz); if (munmap(addr, pagepool_end - addr) != 0) { #ifdef IN_RTLD rtld_fdprintf(STDERR_FILENO, _BASENAME_RTLD ": " "morepages: cannot munmap %p: %s\n", addr, rtld_strerror(errno)); #endif } } offset = (long)pagepool_start - rounddown2((long)pagepool_start, pagesz); pagepool_start = mmap(0, n * pagesz, PROT_READ | PROT_WRITE, MAP_ANON | MAP_PRIVATE, -1, 0); if (pagepool_start == MAP_FAILED) { #ifdef IN_RTLD rtld_fdprintf(STDERR_FILENO, _BASENAME_RTLD ": morepages: " "cannot mmap anonymous memory: %s\n", rtld_strerror(errno)); #endif return (0); } pagepool_end = pagepool_start + n * pagesz; pagepool_start += offset; return (n); }