diff options
| author | Leah Rowe <leah@libreboot.org> | 2025-01-26 07:25:26 +0000 |
|---|---|---|
| committer | Leah Rowe <leah@libreboot.org> | 2025-01-26 07:25:26 +0000 |
| commit | 98e105ac4f186428bc9df238507c64b5f51ff12a (patch) | |
| tree | 53b38dc3bde25d73046a479d9573fa551dc81650 | |
| parent | 52e8ea57f7b1cef262939696e8012835dc4f7e59 (diff) | |
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>
| -rw-r--r-- | util/nvmutil/nvmutil.c | 20 |
1 files changed, 13 insertions, 7 deletions
diff --git a/util/nvmutil/nvmutil.c b/util/nvmutil/nvmutil.c index 9b672ae0..f5f80875 100644 --- a/util/nvmutil/nvmutil.c +++ b/util/nvmutil/nvmutil.c @@ -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) */ |