canoeboot
/
cbmk
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

util/nvmutil: allocate less memory for setchecksum 

also cmd_brick

where the checksum is being corrected or bricked, we
only need to handle the 128-byte nvm area on one of
the parts

similarly, we only need to allocate half the gbe file
size when doing a copy command.

256 bytes still allocated for setmac (see previous
commit), because we verify both checksums and set both
parts if possible.

with this, nvmutil is now much more memory-efficient.

Signed-off-by: Leah Rowe <leah@libreboot.org>
20250107_branch
Leah Rowe 2025-01-26 07:25:26 +00:00
parent 741ef57efc
commit e2be86695a
1 changed files with 13 additions and 7 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

20
util/nvmutil/nvmutil.c
View File

@ -33,7 +33,7 @@ uint8_t hextonum(char chs), rhex(void);
uint16_t mac[3] = {0, 0, 0};
size_t partsize, nf, gbe[2];
uint8_t nvmPartChanged[2] = {0, 0}, skipread[2] = {0, 0};
uint8_t nvmPartChanged[2] = {0, 0}, do_read[2] = {1, 1};
int e = 1, flags, rfd, fd, part, gbeFileChanged = 0;
const char *strMac = NULL, *strRMac = "??:??:??:??:??:??", *filename = NULL;
@ -204,18 +204,22 @@ readGbe(void)
nf = 128; /* only read/write the nvm part of the block */
if ((cmd == cmd_copy) || (cmd == cmd_setchecksum) || (cmd == cmd_brick))
skipread[part ^ 1] = 1; /* only read the user-specified part */
do_read[part ^ 1] = 0; /* only read the user-specified part */
char *buf = malloc(nf << 1);
/* AND do_read[*] to avoid wasteful malloc */
/* cmd_copy also relies on this */
char *buf = malloc(nf << (do_read[0] & do_read[1]));
if (buf == NULL)
err(errno, "Can't malloc %ld B for '%s'", partsize, filename);
/* we pread per-part, so each part has its own pointer: */
/* if a do_read is 0, both pointers are the same; this accomplishes
the desired result for cmd_copy (see cmd_copy function) */
gbe[0] = (size_t) buf;
gbe[1] = gbe[0] + nf;
gbe[1] = gbe[0] + (nf * (do_read[0] & do_read[1]));
for (int p = 0; p < 2; p++) {
if (skipread[p])
if (!do_read[p])
continue; /* avoid unnecessary reads */
err_if(pread(fd, (uint8_t *) gbe[p], nf, p * partsize) == -1);
@ -369,8 +373,10 @@ cmd_brick(void)
void
cmd_copy(void)
{
if ((gbeFileChanged = nvmPartChanged[part ^ 1] = goodChecksum(part)))
gbe[part ^ 1] = gbe[part]; /* speedhack: copy ptr, not words */
gbeFileChanged = nvmPartChanged[part ^ 1] = goodChecksum(part);
/* no need to actually copy because gbe[] pointers are both the same */
/* we simply set the right nvm part as changed, and write the file */
}
/* verify nvm part checksum (return 1 if valid) */