Patrick Georgi submitted this change.
drivers/smmstore: Fix some issues
This fixes the following:
- Fix smmstore_read_region to actually read stuff
- Clean up the code a little
- Change the loglevel for non error messages to BIOS_DEBUG
- Use an incoherent rdev to potentially speed up reading access
TESTED on google/wolf with out of tree patch to hook up smmstore to
sb/intel/lynxpoint.
Change-Id: I629be25d2a9b65796ae8f7a700b6bdab57b91b22
Signed-off-by: Arthur Heymans <arthur@aheymans.xyz>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/30432
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Patrick Georgi <pgeorgi@google.com>
---
M src/drivers/smmstore/store.c
1 file changed, 104 insertions(+), 64 deletions(-)
diff --git a/src/drivers/smmstore/store.c b/src/drivers/smmstore/store.c
index dc4a0cf..23d2af0 100644
--- a/src/drivers/smmstore/store.c
+++ b/src/drivers/smmstore/store.c
@@ -43,6 +43,33 @@
* crash/reboot could clear out all variables.
*/
+static enum cb_err lookup_store_region(struct region *region)
+{
+ if (CONFIG(SMMSTORE_IN_CBFS)) {
+ struct cbfsf file;
+ if (cbfs_locate_file_in_region(&file,
+ CONFIG_SMMSTORE_REGION,
+ CONFIG_SMMSTORE_FILENAME, NULL) < 0) {
+ printk(BIOS_WARNING,
+ "smm store: Unable to find SMM store file in region '%s'\n",
+ CONFIG_SMMSTORE_REGION);
+ return CB_ERR;
+ }
+ struct region_device rdev;
+ cbfs_file_data(&rdev, &file);
+ *region = *region_device_region(&rdev);
+ } else {
+ if (fmap_locate_area(CONFIG_SMMSTORE_REGION, region)) {
+ printk(BIOS_WARNING,
+ "smm store: Unable to find SMM store FMAP region '%s'\n",
+ CONFIG_SMMSTORE_REGION);
+ return CB_ERR;
+ }
+ }
+
+ return CB_SUCCESS;
+}
+
/*
* Return a region device that points into the store file.
*
@@ -57,28 +84,26 @@
*/
static int lookup_store(struct region_device *rstore)
{
- struct cbfsf file;
- if (CONFIG(SMMSTORE_IN_CBFS)) {
- if (cbfs_locate_file_in_region(&file,
- CONFIG_SMMSTORE_REGION,
- CONFIG_SMMSTORE_FILENAME, NULL) < 0) {
- printk(BIOS_WARNING, "smm store: "
- "Unable to find SMM store file in region '%s'\n",
- CONFIG_SMMSTORE_REGION);
- return -1;
- }
+ static struct region_device read_rdev, write_rdev;
+ static struct incoherent_rdev store_irdev;
+ struct region region;
+ const struct region_device *rdev;
- cbfs_file_data(rstore, &file);
- } else {
- if (fmap_locate_area_as_rdev_rw(CONFIG_SMMSTORE_REGION, rstore)) {
- printk(BIOS_WARNING,
- "smm store: Unable to find SMM store FMAP region '%s'\n",
- CONFIG_SMMSTORE_REGION);
- return -1;
- }
- }
+ if (lookup_store_region(®ion) != CB_SUCCESS)
+ return -1;
- return 0;
+ if (boot_device_ro_subregion(®ion, &read_rdev) < 0)
+ return -1;
+
+ if (boot_device_rw_subregion(®ion, &write_rdev) < 0)
+ return -1;
+
+ rdev = incoherent_rdev_init(&store_irdev, ®ion, &read_rdev, &write_rdev);
+
+ if (rdev == NULL)
+ return -1;
+
+ return rdev_chain(rstore, rdev, 0, region_device_sz(rdev));
}
/*
@@ -94,13 +119,12 @@
if (bufsize == NULL)
return -1;
- *bufsize = 0;
if (lookup_store(&store) < 0) {
printk(BIOS_WARNING, "reading region failed\n");
return -1;
}
- ssize_t tx = min(*bufsize, region_device_sz(&store));
+ ssize_t tx = MIN(*bufsize, region_device_sz(&store));
*bufsize = rdev_readat(&store, buf, 0, tx);
if (*bufsize < 0)
@@ -109,33 +133,19 @@
return 0;
}
-/*
- * Append data to region
- *
- * Returns 0 on success, -1 on failure
- */
-int smmstore_append_data(void *key, uint32_t key_sz,
- void *value, uint32_t value_sz)
+static enum cb_err scan_end(struct region_device *store)
{
- struct region_device store;
-
- if (lookup_store(&store) < 0) {
- printk(BIOS_WARNING, "reading region failed\n");
- return -1;
- }
-
- ssize_t data_sz = region_device_sz(&store);
-
/* scan for end */
ssize_t end = 0;
uint32_t k_sz, v_sz;
+ const ssize_t data_sz = region_device_sz(store);
while (end < data_sz) {
/* make odd corner cases identifiable, eg. invalid v_sz */
k_sz = 0;
- if (rdev_readat(&store, &k_sz, end, sizeof(k_sz)) < 0) {
+ if (rdev_readat(store, &k_sz, end, sizeof(k_sz)) < 0) {
printk(BIOS_WARNING, "failed reading key size\n");
- return -1;
+ return CB_ERR;
}
/* found the end */
@@ -148,65 +158,95 @@
*/
if (k_sz > data_sz) {
printk(BIOS_WARNING, "key size out of bounds\n");
- return -1;
+ return CB_ERR;
}
- if (rdev_readat(&store, &v_sz, end + 4, sizeof(v_sz)) < 0) {
+ if (rdev_readat(store, &v_sz, end + sizeof(k_sz), sizeof(v_sz)) < 0) {
printk(BIOS_WARNING, "failed reading value size\n");
- return -1;
+ return CB_ERR;
}
if (v_sz > data_sz) {
printk(BIOS_WARNING, "value size out of bounds\n");
- return -1;
+ return CB_ERR;
}
- end += 8 + k_sz + v_sz + 1;
+ end += sizeof(k_sz) + sizeof(v_sz) + k_sz + v_sz + 1;
end = ALIGN_UP(end, sizeof(uint32_t));
}
- printk(BIOS_WARNING, "used smm store size might be 0x%zx bytes\n", end);
+ printk(BIOS_DEBUG, "used smm store size might be 0x%zx bytes\n", end);
if (k_sz != 0xffffffff) {
printk(BIOS_WARNING,
"eof of data marker looks invalid: 0x%x\n", k_sz);
+ return CB_ERR;
+ }
+
+ if (rdev_chain(store, store, end, data_sz - end))
+ return CB_ERR;
+
+ return CB_SUCCESS;
+
+}
+/*
+ * Append data to region
+ *
+ * Returns 0 on success, -1 on failure
+ */
+int smmstore_append_data(void *key, uint32_t key_sz, void *value,
+ uint32_t value_sz)
+{
+ struct region_device store;
+
+ if (lookup_store(&store) < 0) {
+ printk(BIOS_WARNING, "reading region failed\n");
return -1;
}
- printk(BIOS_WARNING, "used size looks legit\n");
+ ssize_t offset = 0;
+ ssize_t size;
+ uint8_t nul = 0;
+ if (scan_end(&store) != CB_SUCCESS)
+ return -1;
- printk(BIOS_WARNING, "open (%zx, %zx) for writing\n",
+ printk(BIOS_DEBUG, "used size looks legit\n");
+
+ printk(BIOS_DEBUG, "open (%zx, %zx) for writing\n",
region_device_offset(&store), region_device_sz(&store));
- if (boot_device_rw_subregion(&store.region, &store) < 0) {
- printk(BIOS_WARNING, "couldn't open store for writing\n");
- return -1;
- }
- uint32_t record_sz = 8 + key_sz + value_sz + 1;
- if (end + record_sz >= data_sz) {
+ size = sizeof(key_sz) + sizeof(value_sz) + key_sz + value_sz
+ + sizeof(nul);
+ if (rdev_chain(&store, &store, 0, size)) {
printk(BIOS_WARNING, "not enough space for new data\n");
return -1;
}
- if (rdev_writeat(&store, &key_sz, end, 4) != 4) {
+ if (rdev_writeat(&store, &key_sz, offset, sizeof(key_sz))
+ != sizeof(key_sz)) {
printk(BIOS_WARNING, "failed writing key size\n");
+ return -1;
}
- end += 4;
- if (rdev_writeat(&store, &value_sz, end, 4) != 4) {
+ offset += sizeof(key_sz);
+ if (rdev_writeat(&store, &value_sz, offset, sizeof(value_sz))
+ != sizeof(value_sz)) {
printk(BIOS_WARNING, "failed writing value size\n");
+ return -1;
}
- end += 4;
- if (rdev_writeat(&store, key, end, key_sz) != key_sz) {
+ offset += sizeof(value_sz);
+ if (rdev_writeat(&store, key, offset, key_sz) != key_sz) {
printk(BIOS_WARNING, "failed writing key data\n");
+ return -1;
}
- end += key_sz;
- if (rdev_writeat(&store, value, end, value_sz) != value_sz) {
+ offset += key_sz;
+ if (rdev_writeat(&store, value, offset, value_sz) != value_sz) {
printk(BIOS_WARNING, "failed writing value data\n");
+ return -1;
}
- end += value_sz;
- uint8_t nul = 0;
- if (rdev_writeat(&store, &nul, end, 1) != 1) {
+ offset += value_sz;
+ if (rdev_writeat(&store, &nul, offset, sizeof(nul)) != sizeof(nul)) {
printk(BIOS_WARNING, "failed writing termination\n");
+ return -1;
}
return 0;
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