863 lines
25 KiB
C
863 lines
25 KiB
C
/* mm.c - functions for memory manager */
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/*
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* GRUB -- GRand Unified Bootloader
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* Copyright (C) 2002,2005,2007,2008,2009 Free Software Foundation, Inc.
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*
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* GRUB is free software: you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation, either version 3 of the License, or
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* (at your option) any later version.
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*
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* GRUB is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with GRUB. If not, see <http://www.gnu.org/licenses/>.
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*/
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/*
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The design of this memory manager.
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This is a simple implementation of malloc with a few extensions. These are
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the extensions:
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- memalign is implemented efficiently.
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- multiple regions may be used as free space. They may not be
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contiguous.
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- if existing regions are insufficient to satisfy an allocation, a new
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region can be requested from firmware.
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Regions are managed by a singly linked list, and the meta information is
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stored in the beginning of each region. Space after the meta information
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is used to allocate memory.
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The memory space is used as cells instead of bytes for simplicity. This
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is important for some CPUs which may not access multiple bytes at a time
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when the first byte is not aligned at a certain boundary (typically,
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4-byte or 8-byte). The size of each cell is equal to the size of struct
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grub_mm_header, so the header of each allocated/free block fits into one
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cell precisely. One cell is 16 bytes on 32-bit platforms and 32 bytes
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on 64-bit platforms.
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There are two types of blocks: allocated blocks and free blocks.
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In allocated blocks, the header of each block has only its size. Note that
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this size is based on cells but not on bytes. The header is located right
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before the returned pointer, that is, the header resides at the previous
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cell.
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Free blocks constitutes a ring, using a singly linked list. The first free
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block is pointed to by the meta information of a region. The allocator
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attempts to pick up the second block instead of the first one. This is
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a typical optimization against defragmentation, and makes the
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implementation a bit easier.
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For safety, both allocated blocks and free ones are marked by magic
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numbers. Whenever anything unexpected is detected, GRUB aborts the
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operation.
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*/
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#include <config.h>
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#include <grub/mm.h>
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#include <grub/misc.h>
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#include <grub/err.h>
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#include <grub/types.h>
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#include <grub/disk.h>
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#include <grub/dl.h>
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#include <grub/i18n.h>
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#include <grub/mm_private.h>
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#include <grub/safemath.h>
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#ifdef MM_DEBUG
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# undef grub_calloc
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# undef grub_malloc
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# undef grub_zalloc
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# undef grub_realloc
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# undef grub_free
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# undef grub_memalign
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#endif
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/*
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* GRUB_MM_MGMT_OVERHEAD is an upper bound of management overhead of
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* each region, with any possible padding taken into account.
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*
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* The value must be large enough to make sure grub_memalign(align, size)
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* always succeeds after a successful call to
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* grub_mm_init_region(addr, size + align + GRUB_MM_MGMT_OVERHEAD),
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* for any given addr, align and size (assuming no interger overflow).
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*
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* The worst case which has maximum overhead is shown in the figure below:
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*
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* +-- addr
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* v |<- size + align ->|
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* +---------+----------------+----------------+------------------+---------+
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* | padding | grub_mm_region | grub_mm_header | usable bytes | padding |
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* +---------+----------------+----------------+------------------+---------+
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* |<- a ->|<- b ->|<- c ->|<- d ->|<- e ->|
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* ^
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* b == sizeof (struct grub_mm_region) | / Assuming no other suitable
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* c == sizeof (struct grub_mm_header) | | block is available, then:
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* d == size + align +-| If align == 0, this will be
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* | the pointer returned by next
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* Assuming addr % GRUB_MM_ALIGN == 1, then: | grub_memalign(align, size).
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* a == GRUB_MM_ALIGN - 1 | If align > 0, this chunk may
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* | need to be split to fulfill
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* Assuming d % GRUB_MM_ALIGN == 1, then: | alignment requirements, and
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* e == GRUB_MM_ALIGN - 1 | the returned pointer may be
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* \ inside these usable bytes.
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* Therefore, the maximum overhead is:
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* a + b + c + e == (GRUB_MM_ALIGN - 1) + sizeof (struct grub_mm_region)
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* + sizeof (struct grub_mm_header) + (GRUB_MM_ALIGN - 1)
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*/
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#define GRUB_MM_MGMT_OVERHEAD ((GRUB_MM_ALIGN - 1) \
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+ sizeof (struct grub_mm_region) \
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+ sizeof (struct grub_mm_header) \
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+ (GRUB_MM_ALIGN - 1))
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/* The size passed to grub_mm_add_region_fn() is aligned up by this value. */
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#define GRUB_MM_HEAP_GROW_ALIGN 4096
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/* Minimal heap growth granularity when existing heap space is exhausted. */
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#define GRUB_MM_HEAP_GROW_EXTRA 0x100000
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grub_mm_region_t grub_mm_base;
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grub_mm_add_region_func_t grub_mm_add_region_fn;
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/* Get a header from the pointer PTR, and set *P and *R to a pointer
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to the header and a pointer to its region, respectively. PTR must
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be allocated. */
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static void
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get_header_from_pointer (void *ptr, grub_mm_header_t *p, grub_mm_region_t *r)
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{
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if ((grub_addr_t) ptr & (GRUB_MM_ALIGN - 1))
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grub_fatal ("unaligned pointer %p", ptr);
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for (*r = grub_mm_base; *r; *r = (*r)->next)
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if ((grub_addr_t) ptr > (grub_addr_t) ((*r) + 1)
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&& (grub_addr_t) ptr <= (grub_addr_t) ((*r) + 1) + (*r)->size)
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break;
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if (! *r)
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grub_fatal ("out of range pointer %p", ptr);
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*p = (grub_mm_header_t) ptr - 1;
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if ((*p)->magic == GRUB_MM_FREE_MAGIC)
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grub_fatal ("double free at %p", *p);
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if ((*p)->magic != GRUB_MM_ALLOC_MAGIC)
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grub_fatal ("alloc magic is broken at %p: %lx", *p,
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(unsigned long) (*p)->magic);
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}
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/* Initialize a region starting from ADDR and whose size is SIZE,
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to use it as free space. */
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void
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grub_mm_init_region (void *addr, grub_size_t size)
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{
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grub_mm_header_t h;
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grub_mm_region_t r, *p, q;
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grub_dprintf ("regions", "Using memory for heap: start=%p, end=%p\n",
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addr, (char *) addr + (unsigned int) size);
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/* Exclude last 4K to avoid overflows. */
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/* If addr + 0x1000 overflows then whole region is in excluded zone. */
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if ((grub_addr_t) addr > ~((grub_addr_t) 0x1000))
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return;
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/* If addr + 0x1000 + size overflows then decrease size. */
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if (((grub_addr_t) addr + 0x1000) > ~(grub_addr_t) size)
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size = ((grub_addr_t) -0x1000) - (grub_addr_t) addr;
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/* Attempt to merge this region with every existing region */
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for (p = &grub_mm_base, q = *p; q; p = &(q->next), q = *p)
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{
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/*
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* Is the new region immediately below an existing region? That
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* is, is the address of the memory we're adding now (addr) + size
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* of the memory we're adding (size) + the bytes we couldn't use
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* at the start of the region we're considering (q->pre_size)
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* equal to the address of q? In other words, does the memory
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* looks like this?
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*
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* addr q
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* |----size-----|-q->pre_size-|<q region>|
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*/
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grub_dprintf ("regions", "Can we extend into region above?"
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" %p + %" PRIxGRUB_SIZE " + %" PRIxGRUB_SIZE " ?=? %p\n",
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(grub_uint8_t *) addr, size, q->pre_size, (grub_uint8_t *) q);
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if ((grub_uint8_t *) addr + size + q->pre_size == (grub_uint8_t *) q)
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{
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grub_dprintf ("regions", "Yes: extending a region: (%p -> %p) -> (%p -> %p)\n",
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q, (grub_uint8_t *) q + sizeof (*q) + q->size,
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addr, (grub_uint8_t *) q + sizeof (*q) + q->size);
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/*
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* Yes, we can merge the memory starting at addr into the
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* existing region from below. Align up addr to GRUB_MM_ALIGN
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* so that our new region has proper alignment.
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*/
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r = (grub_mm_region_t) ALIGN_UP ((grub_addr_t) addr, GRUB_MM_ALIGN);
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/* Copy the region data across */
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*r = *q;
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/* Consider all the new size as pre-size */
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r->pre_size += size;
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/*
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* If we have enough pre-size to create a block, create a
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* block with it. Mark it as allocated and pass it to
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* grub_free (), which will sort out getting it into the free
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* list.
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*/
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if (r->pre_size >> GRUB_MM_ALIGN_LOG2)
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{
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h = (grub_mm_header_t) (r + 1);
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/* block size is pre-size converted to cells */
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h->size = (r->pre_size >> GRUB_MM_ALIGN_LOG2);
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h->magic = GRUB_MM_ALLOC_MAGIC;
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/* region size grows by block size converted back to bytes */
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r->size += h->size << GRUB_MM_ALIGN_LOG2;
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/* adjust pre_size to be accurate */
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r->pre_size &= (GRUB_MM_ALIGN - 1);
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*p = r;
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grub_free (h + 1);
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}
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/* Replace the old region with the new region */
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*p = r;
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return;
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}
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/*
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* Is the new region immediately above an existing region? That
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* is:
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* q addr
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* |<q region>|-q->post_size-|----size-----|
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*/
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grub_dprintf ("regions", "Can we extend into region below?"
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" %p + %x + %" PRIxGRUB_SIZE " + %" PRIxGRUB_SIZE " ?=? %p\n",
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(grub_uint8_t *) q, (int) sizeof (*q), q->size, q->post_size, (grub_uint8_t *) addr);
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if ((grub_uint8_t *) q + sizeof (*q) + q->size + q->post_size ==
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(grub_uint8_t *) addr)
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{
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grub_dprintf ("regions", "Yes: extending a region: (%p -> %p) -> (%p -> %p)\n",
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q, (grub_uint8_t *) q + sizeof (*q) + q->size,
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q, (grub_uint8_t *) addr + size);
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/*
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* Yes! Follow a similar pattern to above, but simpler.
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* Our header starts at address - post_size, which should align us
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* to a cell boundary.
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*
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* Cast to (void *) first to avoid the following build error:
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* kern/mm.c: In function ‘grub_mm_init_region’:
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* kern/mm.c:211:15: error: cast increases required alignment of target type [-Werror=cast-align]
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* 211 | h = (grub_mm_header_t) ((grub_uint8_t *) addr - q->post_size);
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* | ^
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* It is safe to do that because proper alignment is enforced in grub_mm_size_sanity_check().
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*/
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h = (grub_mm_header_t)(void *) ((grub_uint8_t *) addr - q->post_size);
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/* our size is the allocated size plus post_size, in cells */
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h->size = (size + q->post_size) >> GRUB_MM_ALIGN_LOG2;
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h->magic = GRUB_MM_ALLOC_MAGIC;
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/* region size grows by block size converted back to bytes */
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q->size += h->size << GRUB_MM_ALIGN_LOG2;
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/* adjust new post_size to be accurate */
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q->post_size = (q->post_size + size) & (GRUB_MM_ALIGN - 1);
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grub_free (h + 1);
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return;
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}
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}
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grub_dprintf ("regions", "No: considering a new region at %p of size %" PRIxGRUB_SIZE "\n",
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addr, size);
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/*
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* If you want to modify the code below, please also take a look at
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* GRUB_MM_MGMT_OVERHEAD and make sure it is synchronized with the code.
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*/
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/* Allocate a region from the head. */
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r = (grub_mm_region_t) ALIGN_UP ((grub_addr_t) addr, GRUB_MM_ALIGN);
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/* If this region is too small, ignore it. */
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if (size < GRUB_MM_ALIGN + (char *) r - (char *) addr + sizeof (*r))
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return;
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size -= (char *) r - (char *) addr + sizeof (*r);
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h = (grub_mm_header_t) (r + 1);
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h->next = h;
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h->magic = GRUB_MM_FREE_MAGIC;
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h->size = (size >> GRUB_MM_ALIGN_LOG2);
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r->first = h;
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r->pre_size = (grub_addr_t) r - (grub_addr_t) addr;
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r->size = (h->size << GRUB_MM_ALIGN_LOG2);
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r->post_size = size - r->size;
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/* Find where to insert this region. Put a smaller one before bigger ones,
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to prevent fragmentation. */
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for (p = &grub_mm_base, q = *p; q; p = &(q->next), q = *p)
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if (q->size > r->size)
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break;
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*p = r;
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r->next = q;
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}
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/* Allocate the number of units N with the alignment ALIGN from the ring
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* buffer given in *FIRST. ALIGN must be a power of two. Both N and
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* ALIGN are in units of GRUB_MM_ALIGN. Return a non-NULL if successful,
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* otherwise return NULL.
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*
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* Note: because in certain circumstances we need to adjust the ->next
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* pointer of the previous block, we iterate over the singly linked
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* list with the pair (prev, cur). *FIRST is our initial previous, and
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* *FIRST->next is our initial current pointer. So we will actually
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* allocate from *FIRST->next first and *FIRST itself last.
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*/
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static void *
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grub_real_malloc (grub_mm_header_t *first, grub_size_t n, grub_size_t align)
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{
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grub_mm_header_t cur, prev;
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/* When everything is allocated side effect is that *first will have alloc
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magic marked, meaning that there is no room in this region. */
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if ((*first)->magic == GRUB_MM_ALLOC_MAGIC)
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return 0;
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/* Try to search free slot for allocation in this memory region. */
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for (prev = *first, cur = prev->next; ; prev = cur, cur = cur->next)
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{
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grub_off_t extra;
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extra = ((grub_addr_t) (cur + 1) >> GRUB_MM_ALIGN_LOG2) & (align - 1);
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if (extra)
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extra = align - extra;
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if (! cur)
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grub_fatal ("null in the ring");
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if (cur->magic != GRUB_MM_FREE_MAGIC)
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grub_fatal ("free magic is broken at %p: 0x%x", cur, cur->magic);
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if (cur->size >= n + extra)
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{
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extra += (cur->size - extra - n) & (~(align - 1));
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if (extra == 0 && cur->size == n)
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{
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/* There is no special alignment requirement and memory block
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is complete match.
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1. Just mark memory block as allocated and remove it from
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free list.
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Result:
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+---------------+ previous block's next
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| alloc, size=n | |
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+---------------+ v
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*/
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prev->next = cur->next;
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}
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else if (align == 1 || cur->size == n + extra)
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{
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/* There might be alignment requirement, when taking it into
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account memory block fits in.
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1. Allocate new area at end of memory block.
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2. Reduce size of available blocks from original node.
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3. Mark new area as allocated and "remove" it from free
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list.
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Result:
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+---------------+
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| free, size-=n | next --+
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+---------------+ |
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| alloc, size=n | |
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+---------------+ v
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*/
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cur->size -= n;
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cur += cur->size;
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}
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else if (extra == 0)
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{
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grub_mm_header_t r;
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r = cur + extra + n;
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r->magic = GRUB_MM_FREE_MAGIC;
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r->size = cur->size - extra - n;
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r->next = cur->next;
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prev->next = r;
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if (prev == cur)
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{
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prev = r;
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r->next = r;
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}
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}
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else
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{
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/* There is alignment requirement and there is room in memory
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block. Split memory block to three pieces.
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1. Create new memory block right after section being
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allocated. Mark it as free.
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2. Add new memory block to free chain.
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3. Mark current memory block having only extra blocks.
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4. Advance to aligned block and mark that as allocated and
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"remove" it from free list.
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Result:
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+------------------------------+
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| free, size=extra | next --+
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+------------------------------+ |
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| alloc, size=n | |
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+------------------------------+ |
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| free, size=orig.size-extra-n | <------+, next --+
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+------------------------------+ v
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*/
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grub_mm_header_t r;
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r = cur + extra + n;
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r->magic = GRUB_MM_FREE_MAGIC;
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r->size = cur->size - extra - n;
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r->next = cur;
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cur->size = extra;
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prev->next = r;
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cur += extra;
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}
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cur->magic = GRUB_MM_ALLOC_MAGIC;
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cur->size = n;
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/* Mark find as a start marker for next allocation to fasten it.
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This will have side effect of fragmenting memory as small
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pieces before this will be un-used. */
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/* So do it only for chunks under 32K. */
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if (n < (0x8000 >> GRUB_MM_ALIGN_LOG2)
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|| *first == cur)
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*first = prev;
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return cur + 1;
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}
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/* Search was completed without result. */
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if (cur == *first)
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break;
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}
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return 0;
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}
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/* Allocate SIZE bytes with the alignment ALIGN and return the pointer. */
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void *
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grub_memalign (grub_size_t align, grub_size_t size)
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{
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grub_mm_region_t r;
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grub_size_t n = ((size + GRUB_MM_ALIGN - 1) >> GRUB_MM_ALIGN_LOG2) + 1;
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grub_size_t grow;
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int count = 0;
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if (!grub_mm_base)
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goto fail;
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if (size > ~(grub_size_t) align)
|
||
goto fail;
|
||
|
||
grow = size + align;
|
||
|
||
/* We currently assume at least a 32-bit grub_size_t,
|
||
so limiting allocations to <adress space size> - 1MiB
|
||
in name of sanity is beneficial. */
|
||
if (grow > ~(grub_size_t) 0x100000)
|
||
goto fail;
|
||
|
||
align = (align >> GRUB_MM_ALIGN_LOG2);
|
||
if (align == 0)
|
||
align = 1;
|
||
|
||
again:
|
||
|
||
for (r = grub_mm_base; r; r = r->next)
|
||
{
|
||
void *p;
|
||
|
||
p = grub_real_malloc (&(r->first), n, align);
|
||
if (p)
|
||
return p;
|
||
}
|
||
|
||
/* If failed, increase free memory somehow. */
|
||
switch (count)
|
||
{
|
||
case 0:
|
||
/* Request additional pages, contiguous */
|
||
count++;
|
||
|
||
/*
|
||
* Calculate the necessary size of heap growth (if applicable),
|
||
* with region management overhead taken into account.
|
||
*/
|
||
if (grub_add (grow, GRUB_MM_MGMT_OVERHEAD, &grow))
|
||
goto fail;
|
||
|
||
/* Preallocate some extra space if heap growth is small. */
|
||
grow = grub_max (grow, GRUB_MM_HEAP_GROW_EXTRA);
|
||
|
||
/* Align up heap growth to make it friendly to CPU/MMU. */
|
||
if (grow > ~(grub_size_t) (GRUB_MM_HEAP_GROW_ALIGN - 1))
|
||
goto fail;
|
||
grow = ALIGN_UP (grow, GRUB_MM_HEAP_GROW_ALIGN);
|
||
|
||
/* Do the same sanity check again. */
|
||
if (grow > ~(grub_size_t) 0x100000)
|
||
goto fail;
|
||
|
||
if (grub_mm_add_region_fn != NULL &&
|
||
grub_mm_add_region_fn (grow, GRUB_MM_ADD_REGION_CONSECUTIVE) == GRUB_ERR_NONE)
|
||
goto again;
|
||
|
||
/* fallthrough */
|
||
|
||
case 1:
|
||
/* Request additional pages, anything at all */
|
||
count++;
|
||
|
||
if (grub_mm_add_region_fn != NULL)
|
||
{
|
||
/*
|
||
* Try again even if this fails, in case it was able to partially
|
||
* satisfy the request
|
||
*/
|
||
grub_mm_add_region_fn (grow, GRUB_MM_ADD_REGION_NONE);
|
||
goto again;
|
||
}
|
||
|
||
/* fallthrough */
|
||
|
||
case 2:
|
||
/* Invalidate disk caches. */
|
||
grub_disk_cache_invalidate_all ();
|
||
count++;
|
||
goto again;
|
||
|
||
default:
|
||
break;
|
||
}
|
||
|
||
fail:
|
||
grub_error (GRUB_ERR_OUT_OF_MEMORY, N_("out of memory"));
|
||
return 0;
|
||
}
|
||
|
||
/*
|
||
* Allocate NMEMB instances of SIZE bytes and return the pointer, or error on
|
||
* integer overflow.
|
||
*/
|
||
void *
|
||
grub_calloc (grub_size_t nmemb, grub_size_t size)
|
||
{
|
||
void *ret;
|
||
grub_size_t sz = 0;
|
||
|
||
if (grub_mul (nmemb, size, &sz))
|
||
{
|
||
grub_error (GRUB_ERR_OUT_OF_RANGE, N_("overflow is detected"));
|
||
return NULL;
|
||
}
|
||
|
||
ret = grub_memalign (0, sz);
|
||
if (!ret)
|
||
return NULL;
|
||
|
||
grub_memset (ret, 0, sz);
|
||
return ret;
|
||
}
|
||
|
||
/* Allocate SIZE bytes and return the pointer. */
|
||
void *
|
||
grub_malloc (grub_size_t size)
|
||
{
|
||
return grub_memalign (0, size);
|
||
}
|
||
|
||
/* Allocate SIZE bytes, clear them and return the pointer. */
|
||
void *
|
||
grub_zalloc (grub_size_t size)
|
||
{
|
||
void *ret;
|
||
|
||
ret = grub_memalign (0, size);
|
||
if (ret)
|
||
grub_memset (ret, 0, size);
|
||
|
||
return ret;
|
||
}
|
||
|
||
/* Deallocate the pointer PTR. */
|
||
void
|
||
grub_free (void *ptr)
|
||
{
|
||
grub_mm_header_t p;
|
||
grub_mm_region_t r;
|
||
|
||
if (! ptr)
|
||
return;
|
||
|
||
get_header_from_pointer (ptr, &p, &r);
|
||
|
||
if (r->first->magic == GRUB_MM_ALLOC_MAGIC)
|
||
{
|
||
p->magic = GRUB_MM_FREE_MAGIC;
|
||
r->first = p->next = p;
|
||
}
|
||
else
|
||
{
|
||
grub_mm_header_t cur, prev;
|
||
|
||
#if 0
|
||
cur = r->first;
|
||
do
|
||
{
|
||
grub_printf ("%s:%d: q=%p, q->size=0x%x, q->magic=0x%x\n",
|
||
GRUB_FILE, __LINE__, cur, cur->size, cur->magic);
|
||
cur = cur->next;
|
||
}
|
||
while (cur != r->first);
|
||
#endif
|
||
/* Iterate over all blocks in the free ring.
|
||
*
|
||
* The free ring is arranged from high addresses to low
|
||
* addresses, modulo wraparound.
|
||
*
|
||
* We are looking for a block with a higher address than p or
|
||
* whose next address is lower than p.
|
||
*/
|
||
for (prev = r->first, cur = prev->next; cur <= p || cur->next >= p;
|
||
prev = cur, cur = prev->next)
|
||
{
|
||
if (cur->magic != GRUB_MM_FREE_MAGIC)
|
||
grub_fatal ("free magic is broken at %p: 0x%x", cur, cur->magic);
|
||
|
||
/* Deal with wrap-around */
|
||
if (cur <= cur->next && (cur > p || cur->next < p))
|
||
break;
|
||
}
|
||
|
||
/* mark p as free and insert it between cur and cur->next */
|
||
p->magic = GRUB_MM_FREE_MAGIC;
|
||
p->next = cur->next;
|
||
cur->next = p;
|
||
|
||
/*
|
||
* If the block we are freeing can be merged with the next
|
||
* free block, do that.
|
||
*/
|
||
if (p->next + p->next->size == p)
|
||
{
|
||
p->magic = 0;
|
||
|
||
p->next->size += p->size;
|
||
cur->next = p->next;
|
||
p = p->next;
|
||
}
|
||
|
||
r->first = cur;
|
||
|
||
/* Likewise if can be merged with the preceeding free block */
|
||
if (cur == p + p->size)
|
||
{
|
||
cur->magic = 0;
|
||
p->size += cur->size;
|
||
if (cur == prev)
|
||
prev = p;
|
||
prev->next = p;
|
||
cur = prev;
|
||
}
|
||
|
||
/*
|
||
* Set r->first such that the just free()d block is tried first.
|
||
* (An allocation is tried from *first->next, and cur->next == p.)
|
||
*/
|
||
r->first = cur;
|
||
}
|
||
}
|
||
|
||
/* Reallocate SIZE bytes and return the pointer. The contents will be
|
||
the same as that of PTR. */
|
||
void *
|
||
grub_realloc (void *ptr, grub_size_t size)
|
||
{
|
||
grub_mm_header_t p;
|
||
grub_mm_region_t r;
|
||
void *q;
|
||
grub_size_t n;
|
||
|
||
if (! ptr)
|
||
return grub_malloc (size);
|
||
|
||
if (! size)
|
||
{
|
||
grub_free (ptr);
|
||
return 0;
|
||
}
|
||
|
||
/* FIXME: Not optimal. */
|
||
n = ((size + GRUB_MM_ALIGN - 1) >> GRUB_MM_ALIGN_LOG2) + 1;
|
||
get_header_from_pointer (ptr, &p, &r);
|
||
|
||
if (p->size >= n)
|
||
return ptr;
|
||
|
||
q = grub_malloc (size);
|
||
if (! q)
|
||
return q;
|
||
|
||
/* We've already checked that p->size < n. */
|
||
grub_memcpy (q, ptr, p->size << GRUB_MM_ALIGN_LOG2);
|
||
grub_free (ptr);
|
||
return q;
|
||
}
|
||
|
||
#ifdef MM_DEBUG
|
||
int grub_mm_debug = 0;
|
||
|
||
void
|
||
grub_mm_dump_free (void)
|
||
{
|
||
grub_mm_region_t r;
|
||
|
||
for (r = grub_mm_base; r; r = r->next)
|
||
{
|
||
grub_mm_header_t p;
|
||
|
||
grub_printf ("Region %p (size %" PRIuGRUB_SIZE ")\n\n", r, r->size);
|
||
|
||
/* Follow the free list. */
|
||
p = r->first;
|
||
do
|
||
{
|
||
if (p->magic != GRUB_MM_FREE_MAGIC)
|
||
grub_fatal ("free magic is broken at %p: 0x%x", p, p->magic);
|
||
|
||
grub_printf ("F:%p:%u:%p\n",
|
||
p, (unsigned int) p->size << GRUB_MM_ALIGN_LOG2, p->next);
|
||
p = p->next;
|
||
}
|
||
while (p != r->first);
|
||
}
|
||
|
||
grub_printf ("\n");
|
||
}
|
||
|
||
void
|
||
grub_mm_dump (unsigned lineno)
|
||
{
|
||
grub_mm_region_t r;
|
||
|
||
grub_printf ("called at line %u\n", lineno);
|
||
for (r = grub_mm_base; r; r = r->next)
|
||
{
|
||
grub_mm_header_t p;
|
||
|
||
grub_printf ("Region %p (size %" PRIuGRUB_SIZE ")\n\n", r, r->size);
|
||
|
||
for (p = (grub_mm_header_t) ALIGN_UP ((grub_addr_t) (r + 1),
|
||
GRUB_MM_ALIGN);
|
||
(grub_addr_t) p < (grub_addr_t) (r+1) + r->size;
|
||
p++)
|
||
{
|
||
switch (p->magic)
|
||
{
|
||
case GRUB_MM_FREE_MAGIC:
|
||
grub_printf ("F:%p:%u:%p\n",
|
||
p, (unsigned int) p->size << GRUB_MM_ALIGN_LOG2, p->next);
|
||
break;
|
||
case GRUB_MM_ALLOC_MAGIC:
|
||
grub_printf ("A:%p:%u\n", p, (unsigned int) p->size << GRUB_MM_ALIGN_LOG2);
|
||
break;
|
||
}
|
||
}
|
||
}
|
||
|
||
grub_printf ("\n");
|
||
}
|
||
|
||
void *
|
||
grub_debug_calloc (const char *file, int line, grub_size_t nmemb, grub_size_t size)
|
||
{
|
||
void *ptr;
|
||
|
||
if (grub_mm_debug)
|
||
grub_printf ("%s:%d: calloc (0x%" PRIxGRUB_SIZE ", 0x%" PRIxGRUB_SIZE ") = ",
|
||
file, line, nmemb, size);
|
||
ptr = grub_calloc (nmemb, size);
|
||
if (grub_mm_debug)
|
||
grub_printf ("%p\n", ptr);
|
||
return ptr;
|
||
}
|
||
|
||
void *
|
||
grub_debug_malloc (const char *file, int line, grub_size_t size)
|
||
{
|
||
void *ptr;
|
||
|
||
if (grub_mm_debug)
|
||
grub_printf ("%s:%d: malloc (0x%" PRIxGRUB_SIZE ") = ", file, line, size);
|
||
ptr = grub_malloc (size);
|
||
if (grub_mm_debug)
|
||
grub_printf ("%p\n", ptr);
|
||
return ptr;
|
||
}
|
||
|
||
void *
|
||
grub_debug_zalloc (const char *file, int line, grub_size_t size)
|
||
{
|
||
void *ptr;
|
||
|
||
if (grub_mm_debug)
|
||
grub_printf ("%s:%d: zalloc (0x%" PRIxGRUB_SIZE ") = ", file, line, size);
|
||
ptr = grub_zalloc (size);
|
||
if (grub_mm_debug)
|
||
grub_printf ("%p\n", ptr);
|
||
return ptr;
|
||
}
|
||
|
||
void
|
||
grub_debug_free (const char *file, int line, void *ptr)
|
||
{
|
||
if (grub_mm_debug)
|
||
grub_printf ("%s:%d: free (%p)\n", file, line, ptr);
|
||
grub_free (ptr);
|
||
}
|
||
|
||
void *
|
||
grub_debug_realloc (const char *file, int line, void *ptr, grub_size_t size)
|
||
{
|
||
if (grub_mm_debug)
|
||
grub_printf ("%s:%d: realloc (%p, 0x%" PRIxGRUB_SIZE ") = ", file, line, ptr, size);
|
||
ptr = grub_realloc (ptr, size);
|
||
if (grub_mm_debug)
|
||
grub_printf ("%p\n", ptr);
|
||
return ptr;
|
||
}
|
||
|
||
void *
|
||
grub_debug_memalign (const char *file, int line, grub_size_t align,
|
||
grub_size_t size)
|
||
{
|
||
void *ptr;
|
||
|
||
if (grub_mm_debug)
|
||
grub_printf ("%s:%d: memalign (0x%" PRIxGRUB_SIZE ", 0x%" PRIxGRUB_SIZE
|
||
") = ", file, line, align, size);
|
||
ptr = grub_memalign (align, size);
|
||
if (grub_mm_debug)
|
||
grub_printf ("%p\n", ptr);
|
||
return ptr;
|
||
}
|
||
|
||
#endif /* MM_DEBUG */
|