diff options
Diffstat (limited to 'src/drivers/smmstore/store.c')
-rw-r--r-- | src/drivers/smmstore/store.c | 168 |
1 files changed, 104 insertions, 64 deletions
diff --git a/src/drivers/smmstore/store.c b/src/drivers/smmstore/store.c index dc4a0cf75b..23d2af015f 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 @@ int smmstore_read_region(void *buf, ssize_t *bufsize) 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 @@ int smmstore_read_region(void *buf, ssize_t *bufsize) 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 @@ int smmstore_append_data(void *key, uint32_t key_sz, */ 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 -1; + return CB_ERR; } - printk(BIOS_WARNING, "used size looks legit\n"); + if (rdev_chain(store, store, end, data_sz - end)) + return CB_ERR; - printk(BIOS_WARNING, "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 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; } - uint32_t record_sz = 8 + key_sz + value_sz + 1; - if (end + record_sz >= data_sz) { + ssize_t offset = 0; + ssize_t size; + uint8_t nul = 0; + if (scan_end(&store) != CB_SUCCESS) + return -1; + + 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)); + + 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; |