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-rw-r--r--src/lib/selfboot.c537
1 files changed, 115 insertions, 422 deletions
diff --git a/src/lib/selfboot.c b/src/lib/selfboot.c
index fbd1cc4320..c9c8beefd8 100644
--- a/src/lib/selfboot.c
+++ b/src/lib/selfboot.c
@@ -30,200 +30,6 @@
#include <timestamp.h>
#include <cbmem.h>
-static const unsigned long lb_start = (unsigned long)&_program;
-static const unsigned long lb_end = (unsigned long)&_eprogram;
-
-struct segment {
- struct segment *next;
- struct segment *prev;
- unsigned long s_dstaddr;
- unsigned long s_srcaddr;
- unsigned long s_memsz;
- unsigned long s_filesz;
- int compression;
-};
-
-static void segment_insert_before(struct segment *seg, struct segment *new)
-{
- new->next = seg;
- new->prev = seg->prev;
- seg->prev->next = new;
- seg->prev = new;
-}
-
-static void segment_insert_after(struct segment *seg, struct segment *new)
-{
- new->next = seg->next;
- new->prev = seg;
- seg->next->prev = new;
- seg->next = new;
-}
-
-/* The problem:
- * Static executables all want to share the same addresses
- * in memory because only a few addresses are reliably present on
- * a machine, and implementing general relocation is hard.
- *
- * The solution:
- * - Allocate a buffer the size of the coreboot image plus additional
- * required space.
- * - Anything that would overwrite coreboot copy into the lower part of
- * the buffer.
- * - After loading an ELF image copy coreboot to the top of the buffer.
- * - Then jump to the loaded image.
- *
- * Benefits:
- * - Nearly arbitrary standalone executables can be loaded.
- * - coreboot is preserved, so it can be returned to.
- * - The implementation is still relatively simple,
- * and much simpler than the general case implemented in kexec.
- */
-
-static unsigned long bounce_size, bounce_buffer;
-
-static void get_bounce_buffer(unsigned long req_size)
-{
- unsigned long lb_size;
- void *buffer;
-
- /* When the ramstage is relocatable there is no need for a bounce
- * buffer. All payloads should not overlap the ramstage.
- */
- if (IS_ENABLED(CONFIG_RELOCATABLE_RAMSTAGE) ||
- !arch_supports_bounce_buffer()) {
- bounce_buffer = ~0UL;
- bounce_size = 0;
- return;
- }
-
- lb_size = lb_end - lb_start;
- /* Plus coreboot size so I have somewhere
- * to place a copy to return to.
- */
- lb_size = req_size + lb_size;
-
- buffer = bootmem_allocate_buffer(lb_size);
-
- printk(BIOS_SPEW, "Bounce Buffer at %p, %lu bytes\n", buffer, lb_size);
-
- bounce_buffer = (uintptr_t)buffer;
- bounce_size = req_size;
-}
-
-static int overlaps_coreboot(struct segment *seg)
-{
- unsigned long start, end;
- start = seg->s_dstaddr;
- end = start + seg->s_memsz;
- return !((end <= lb_start) || (start >= lb_end));
-}
-
-static int relocate_segment(unsigned long buffer, struct segment *seg)
-{
- /* Modify all segments that want to load onto coreboot
- * to load onto the bounce buffer instead.
- */
- /* ret: 1 : A new segment is inserted before the seg.
- * 0 : A new segment is inserted after the seg, or no new one.
- */
- unsigned long start, middle, end, ret = 0;
-
- printk(BIOS_SPEW, "lb: [0x%016lx, 0x%016lx)\n",
- lb_start, lb_end);
-
- /* I don't conflict with coreboot so get out of here */
- if (!overlaps_coreboot(seg))
- return 0;
-
- if (!arch_supports_bounce_buffer())
- die("bounce buffer not supported");
-
- start = seg->s_dstaddr;
- middle = start + seg->s_filesz;
- end = start + seg->s_memsz;
-
- printk(BIOS_SPEW, "segment: [0x%016lx, 0x%016lx, 0x%016lx)\n",
- start, middle, end);
-
- if (seg->compression == CBFS_COMPRESS_NONE) {
- /* Slice off a piece at the beginning
- * that doesn't conflict with coreboot.
- */
- if (start < lb_start) {
- struct segment *new;
- unsigned long len = lb_start - start;
- new = malloc(sizeof(*new));
- *new = *seg;
- new->s_memsz = len;
- seg->s_memsz -= len;
- seg->s_dstaddr += len;
- seg->s_srcaddr += len;
- if (seg->s_filesz > len) {
- new->s_filesz = len;
- seg->s_filesz -= len;
- } else {
- seg->s_filesz = 0;
- }
-
- /* Order by stream offset */
- segment_insert_before(seg, new);
-
- /* compute the new value of start */
- start = seg->s_dstaddr;
-
- printk(BIOS_SPEW,
- " early: [0x%016lx, 0x%016lx, 0x%016lx)\n",
- new->s_dstaddr,
- new->s_dstaddr + new->s_filesz,
- new->s_dstaddr + new->s_memsz);
-
- ret = 1;
- }
-
- /* Slice off a piece at the end
- * that doesn't conflict with coreboot
- */
- if (end > lb_end) {
- unsigned long len = lb_end - start;
- struct segment *new;
- new = malloc(sizeof(*new));
- *new = *seg;
- seg->s_memsz = len;
- new->s_memsz -= len;
- new->s_dstaddr += len;
- new->s_srcaddr += len;
- if (seg->s_filesz > len) {
- seg->s_filesz = len;
- new->s_filesz -= len;
- } else {
- new->s_filesz = 0;
- }
- /* Order by stream offset */
- segment_insert_after(seg, new);
-
- printk(BIOS_SPEW,
- " late: [0x%016lx, 0x%016lx, 0x%016lx)\n",
- new->s_dstaddr,
- new->s_dstaddr + new->s_filesz,
- new->s_dstaddr + new->s_memsz);
- }
- }
-
- /* Now retarget this segment onto the bounce buffer */
- /* sort of explanation: the buffer is a 1:1 mapping to coreboot.
- * so you will make the dstaddr be this buffer, and it will get copied
- * later to where coreboot lives.
- */
- seg->s_dstaddr = buffer + (seg->s_dstaddr - lb_start);
-
- printk(BIOS_SPEW, " bounce: [0x%016lx, 0x%016lx, 0x%016lx)\n",
- seg->s_dstaddr,
- seg->s_dstaddr + seg->s_filesz,
- seg->s_dstaddr + seg->s_memsz);
-
- return ret;
-}
-
/* Decode a serialized cbfs payload segment
* from memory into native endianness.
*/
@@ -238,200 +44,36 @@ static void cbfs_decode_payload_segment(struct cbfs_payload_segment *segment,
segment->mem_len = read_be32(&src->mem_len);
}
-static int build_self_segment_list(
- struct segment *head,
- struct cbfs_payload *cbfs_payload, uintptr_t *entry)
+static int segment_targets_usable_ram(void *dest, unsigned long memsz)
{
- struct segment *new;
- struct cbfs_payload_segment *current_segment, *first_segment, segment;
-
- memset(head, 0, sizeof(*head));
- head->next = head->prev = head;
-
- first_segment = &cbfs_payload->segments;
-
- for (current_segment = first_segment;; ++current_segment) {
- printk(BIOS_DEBUG,
- "Loading segment from ROM address 0x%p\n",
- current_segment);
-
- cbfs_decode_payload_segment(&segment, current_segment);
+ uintptr_t d = (uintptr_t) dest;
+ if (bootmem_region_targets_usable_ram(d, memsz))
+ return 1;
- switch (segment.type) {
- case PAYLOAD_SEGMENT_PARAMS:
- printk(BIOS_DEBUG, " parameter section (skipped)\n");
- continue;
-
- case PAYLOAD_SEGMENT_CODE:
- case PAYLOAD_SEGMENT_DATA:
- printk(BIOS_DEBUG, " %s (compression=%x)\n",
- segment.type == PAYLOAD_SEGMENT_CODE
- ? "code" : "data", segment.compression);
-
- new = malloc(sizeof(*new));
- new->s_dstaddr = segment.load_addr;
- new->s_memsz = segment.mem_len;
- new->compression = segment.compression;
- new->s_srcaddr = (uintptr_t)
- ((unsigned char *)first_segment)
- + segment.offset;
- new->s_filesz = segment.len;
-
- printk(BIOS_DEBUG,
- " New segment dstaddr 0x%lx memsize 0x%lx srcaddr 0x%lx filesize 0x%lx\n",
- new->s_dstaddr, new->s_memsz, new->s_srcaddr,
- new->s_filesz);
-
- /* Clean up the values */
- if (new->s_filesz > new->s_memsz) {
- new->s_filesz = new->s_memsz;
- printk(BIOS_DEBUG,
- " cleaned up filesize 0x%lx\n",
- new->s_filesz);
- }
- break;
-
- case PAYLOAD_SEGMENT_BSS:
- printk(BIOS_DEBUG, " BSS 0x%p (%d byte)\n", (void *)
- (intptr_t)segment.load_addr, segment.mem_len);
-
- new = malloc(sizeof(*new));
- new->s_filesz = 0;
- new->s_srcaddr = (uintptr_t)
- ((unsigned char *)first_segment)
- + segment.offset;
- new->s_dstaddr = segment.load_addr;
- new->s_memsz = segment.mem_len;
- new->compression = CBFS_COMPRESS_NONE;
- break;
-
- case PAYLOAD_SEGMENT_ENTRY:
- printk(BIOS_DEBUG, " Entry Point 0x%p\n", (void *)
- (intptr_t)segment.load_addr);
-
- *entry = segment.load_addr;
- /* Per definition, a payload always has the entry point
- * as last segment. Thus, we use the occurrence of the
- * entry point as break condition for the loop.
- * Can we actually just look at the number of section?
- */
- return 1;
-
- default:
- /* We found something that we don't know about. Throw
- * hands into the sky and run away!
- */
- printk(BIOS_EMERG, "Bad segment type %x\n",
- segment.type);
- return -1;
- }
+ if (payload_arch_usable_ram_quirk(d, memsz))
+ return 1;
- /* We have found another CODE, DATA or BSS segment */
- /* Insert new segment at the end of the list */
- segment_insert_before(head, new);
- }
-
- return 1;
-}
-
-__weak int payload_arch_usable_ram_quirk(uint64_t start, uint64_t size)
-{
+ printk(BIOS_ERR, "SELF segment doesn't target RAM: 0x%p, %lu bytes\n", dest, memsz);
+ bootmem_dump_ranges();
return 0;
}
-static int payload_targets_usable_ram(struct segment *head)
-{
- struct segment *ptr;
-
- for (ptr = head->next; ptr != head; ptr = ptr->next) {
- if (bootmem_region_targets_usable_ram(ptr->s_dstaddr,
- ptr->s_memsz))
- continue;
-
- if (payload_arch_usable_ram_quirk(ptr->s_dstaddr, ptr->s_memsz))
- continue;
-
- if (arch_supports_bounce_buffer() &&
- bootmem_region_usable_with_bounce(ptr->s_dstaddr,
- ptr->s_memsz)) {
- printk(BIOS_DEBUG,
- "Payload is loaded over non-relocatable "
- "ramstage. Will use bounce-buffer.\n");
- return 1;
- }
-
- /* Payload segment not targeting RAM. */
- printk(BIOS_ERR, "SELF Payload doesn't target RAM:\n");
- printk(BIOS_ERR, "Failed Segment: 0x%lx, %lu bytes\n",
- ptr->s_dstaddr, ptr->s_memsz);
- bootmem_dump_ranges();
- return 0;
- }
-
- return 1;
-}
-
-static int load_self_segments(struct segment *head, struct prog *payload,
- bool check_regions)
+static int load_one_segment(uint8_t *dest,
+ uint8_t *src,
+ size_t len,
+ size_t memsz,
+ uint32_t compression,
+ int flags)
{
- struct segment *ptr;
- unsigned long bounce_high = lb_end;
-
- if (check_regions) {
- if (!payload_targets_usable_ram(head))
- return 0;
- }
-
- for (ptr = head->next; ptr != head; ptr = ptr->next) {
- /*
- * Add segments to bootmem memory map before a bounce buffer is
- * allocated so that there aren't conflicts with the actual
- * payload.
- */
- if (check_regions) {
- bootmem_add_range(ptr->s_dstaddr, ptr->s_memsz,
- BM_MEM_PAYLOAD);
- }
-
- if (!overlaps_coreboot(ptr))
- continue;
- if (ptr->s_dstaddr + ptr->s_memsz > bounce_high)
- bounce_high = ptr->s_dstaddr + ptr->s_memsz;
- }
- get_bounce_buffer(bounce_high - lb_start);
- if (!bounce_buffer) {
- printk(BIOS_ERR, "Could not find a bounce buffer...\n");
- return 0;
- }
-
- for (ptr = head->next; ptr != head; ptr = ptr->next) {
- unsigned char *dest, *src, *middle, *end;
- size_t len, memsz;
- printk(BIOS_DEBUG,
- "Loading Segment: addr: 0x%016lx memsz: 0x%016lx filesz: 0x%016lx\n",
- ptr->s_dstaddr, ptr->s_memsz, ptr->s_filesz);
-
- /* Modify the segment to load onto the bounce_buffer if
- * necessary.
- */
- if (relocate_segment(bounce_buffer, ptr)) {
- ptr = (ptr->prev)->prev;
- continue;
- }
-
- printk(BIOS_DEBUG,
- "Post relocation: addr: 0x%016lx memsz: 0x%016lx filesz: 0x%016lx\n",
- ptr->s_dstaddr, ptr->s_memsz, ptr->s_filesz);
+ unsigned char *middle, *end;
+ printk(BIOS_DEBUG, "Loading Segment: addr: 0x%p memsz: 0x%016zx filesz: 0x%016zx\n",
+ dest, memsz, len);
/* Compute the boundaries of the segment */
- dest = (unsigned char *)(ptr->s_dstaddr);
- src = (unsigned char *)(ptr->s_srcaddr);
- len = ptr->s_filesz;
- memsz = ptr->s_memsz;
end = dest + memsz;
/* Copy data from the initial buffer */
- switch (ptr->compression) {
+ switch (compression) {
case CBFS_COMPRESS_LZMA: {
printk(BIOS_DEBUG, "using LZMA\n");
timestamp_add_now(TS_START_ULZMA);
@@ -456,9 +98,8 @@ static int load_self_segments(struct segment *head, struct prog *payload,
break;
}
default:
- printk(BIOS_INFO, "CBFS: Unknown compression type %d\n",
- ptr->compression);
- return -1;
+ printk(BIOS_INFO, "CBFS: Unknown compression type %d\n", compression);
+ return 0;
}
/* Calculate middle after any changes to len. */
middle = dest + len;
@@ -479,52 +120,111 @@ static int load_self_segments(struct segment *head, struct prog *payload,
memset(middle, 0, end - middle);
}
- /* Copy the data that's outside the area that shadows ramstage
- */
- printk(BIOS_DEBUG, "dest %p, end %p, bouncebuffer %lx\n", dest,
- end, bounce_buffer);
- if ((unsigned long)end > bounce_buffer) {
- if ((unsigned long)dest < bounce_buffer) {
- unsigned char *from = dest;
- unsigned char *to = (unsigned char *)
- (lb_start - (bounce_buffer
- - (unsigned long)dest));
- unsigned long amount = bounce_buffer
- - (unsigned long)dest;
- printk(BIOS_DEBUG,
- "move prefix around: from %p, to %p, amount: %lx\n",
- from, to, amount);
- memcpy(to, from, amount);
- }
- if ((unsigned long)end > bounce_buffer + (lb_end
- - lb_start)) {
- unsigned long from = bounce_buffer + (lb_end
- - lb_start);
- unsigned long to = lb_end;
- unsigned long amount =
- (unsigned long)end - from;
- printk(BIOS_DEBUG,
- "move suffix around: from %lx, to %lx, amount: %lx\n",
- from, to, amount);
- memcpy((char *)to, (char *)from, amount);
- }
- }
-
/*
* Each architecture can perform additional operations
* on the loaded segment
*/
- prog_segment_loaded((uintptr_t)dest, ptr->s_memsz,
- ptr->next == head ? SEG_FINAL : 0);
+ prog_segment_loaded((uintptr_t)dest, memsz, flags);
+
+
+ return 1;
+}
+
+/* Note: this function is a bit dangerous so is not exported.
+ * It assumes you're smart enough not to call it with the very
+ * last segment, since it uses seg + 1 */
+static int last_loadable_segment(struct cbfs_payload_segment *seg)
+{
+ return read_be32(&(seg + 1)->type) == PAYLOAD_SEGMENT_ENTRY;
+}
+
+static int load_payload_segments(
+ struct cbfs_payload_segment *cbfssegs,
+ int check_regions,
+ uintptr_t *entry)
+{
+ uint8_t *dest, *src;
+ size_t filesz, memsz;
+ uint32_t compression;
+ struct cbfs_payload_segment *first_segment, *seg, segment;
+ int flags = 0;
+
+ for (first_segment = seg = cbfssegs;; ++seg) {
+ printk(BIOS_DEBUG, "Loading segment from ROM address 0x%p\n", seg);
+
+ cbfs_decode_payload_segment(&segment, seg);
+ dest = (uint8_t *)(uintptr_t)segment.load_addr;
+ memsz = segment.mem_len;
+ compression = segment.compression;
+ filesz = segment.len;
+
+ switch (segment.type) {
+ case PAYLOAD_SEGMENT_CODE:
+ case PAYLOAD_SEGMENT_DATA:
+ printk(BIOS_DEBUG, " %s (compression=%x)\n",
+ segment.type == PAYLOAD_SEGMENT_CODE
+ ? "code" : "data", segment.compression);
+ src = ((uint8_t *)first_segment) + segment.offset;
+ printk(BIOS_DEBUG,
+ " New segment dstaddr 0x%p memsize 0x%zx srcaddr 0x%p filesize 0x%zx\n",
+ dest, memsz, src, filesz);
+
+ /* Clean up the values */
+ if (filesz > memsz) {
+ filesz = memsz;
+ printk(BIOS_DEBUG, " cleaned up filesize 0x%zx\n", filesz);
+ }
+ break;
+
+ case PAYLOAD_SEGMENT_BSS:
+ printk(BIOS_DEBUG, " BSS 0x%p (%d byte)\n", (void *)
+ (intptr_t)segment.load_addr, segment.mem_len);
+ filesz = 0;
+ src = ((uint8_t *)first_segment) + segment.offset;
+ compression = CBFS_COMPRESS_NONE;
+ break;
+
+ case PAYLOAD_SEGMENT_ENTRY:
+ printk(BIOS_DEBUG, " Entry Point 0x%p\n", (void *)
+ (intptr_t)segment.load_addr);
+
+ *entry = segment.load_addr;
+ /* Per definition, a payload always has the entry point
+ * as last segment. Thus, we use the occurrence of the
+ * entry point as break condition for the loop.
+ */
+ return 0;
+
+ default:
+ /* We found something that we don't know about. Throw
+ * hands into the sky and run away!
+ */
+ printk(BIOS_EMERG, "Bad segment type %x\n", segment.type);
+ return -1;
+ }
+ if (check_regions && !segment_targets_usable_ram(dest, memsz))
+ return -1;
+ /* Note that the 'seg + 1' is safe as we only call this
+ * function on "not the last" * items, since entry
+ * is always last. */
+ if (last_loadable_segment(seg))
+ flags = SEG_FINAL;
+ if (!load_one_segment(dest, src, filesz, memsz, compression, flags))
+ return -1;
}
return 1;
}
+__weak int payload_arch_usable_ram_quirk(uint64_t start, uint64_t size)
+{
+ return 0;
+}
+
bool selfload(struct prog *payload, bool check_regions)
{
uintptr_t entry = 0;
- struct segment head;
+ struct cbfs_payload_segment *cbfssegs;
void *data;
data = rdev_mmap_full(prog_rdev(payload));
@@ -532,21 +232,14 @@ bool selfload(struct prog *payload, bool check_regions)
if (data == NULL)
return false;
- /* Preprocess the self segments */
- if (!build_self_segment_list(&head, data, &entry))
- goto out;
-
- /* Load the segments */
- if (!load_self_segments(&head, payload, check_regions))
+ cbfssegs = &((struct cbfs_payload *)data)->segments;
+ if (load_payload_segments(cbfssegs, check_regions, &entry))
goto out;
printk(BIOS_SPEW, "Loaded segments\n");
rdev_munmap(prog_rdev(payload), data);
- /* Update the payload's area with the bounce buffer information. */
- prog_set_area(payload, (void *)(uintptr_t)bounce_buffer, bounce_size);
-
/* Pass cbtables to payload if architecture desires it. */
prog_set_entry(payload, (void *)entry, cbmem_find(CBMEM_ID_CBTABLE));