diff options
Diffstat (limited to 'fs/pstore/ram_core.c')
-rw-r--r-- | fs/pstore/ram_core.c | 47 |
1 files changed, 37 insertions, 10 deletions
diff --git a/fs/pstore/ram_core.c b/fs/pstore/ram_core.c index 12e21f789194..f375c0735351 100644 --- a/fs/pstore/ram_core.c +++ b/fs/pstore/ram_core.c @@ -12,7 +12,7 @@ * */ -#define pr_fmt(fmt) "persistent_ram: " fmt +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt #include <linux/device.h> #include <linux/err.h> @@ -29,6 +29,16 @@ #include <linux/vmalloc.h> #include <asm/page.h> +/** + * struct persistent_ram_buffer - persistent circular RAM buffer + * + * @sig: + * signature to indicate header (PERSISTENT_RAM_SIG xor PRZ-type value) + * @start: + * offset into @data where the beginning of the stored bytes begin + * @size: + * number of valid bytes stored in @data + */ struct persistent_ram_buffer { uint32_t sig; atomic_t start; @@ -347,7 +357,7 @@ int notrace persistent_ram_write_user(struct persistent_ram_zone *prz, int rem, ret = 0, c = count; size_t start; - if (unlikely(!access_ok(VERIFY_READ, s, count))) + if (unlikely(!access_ok(s, count))) return -EFAULT; if (unlikely(c > prz->buffer_size)) { s += c - prz->buffer_size; @@ -443,7 +453,8 @@ static void *persistent_ram_iomap(phys_addr_t start, size_t size, void *va; if (!request_mem_region(start, size, label ?: "ramoops")) { - pr_err("request mem region (0x%llx@0x%llx) failed\n", + pr_err("request mem region (%s 0x%llx@0x%llx) failed\n", + label ?: "ramoops", (unsigned long long)size, (unsigned long long)start); return NULL; } @@ -489,32 +500,42 @@ static int persistent_ram_post_init(struct persistent_ram_zone *prz, u32 sig, struct persistent_ram_ecc_info *ecc_info) { int ret; + bool zap = !!(prz->flags & PRZ_FLAG_ZAP_OLD); ret = persistent_ram_init_ecc(prz, ecc_info); - if (ret) + if (ret) { + pr_warn("ECC failed %s\n", prz->label); return ret; + } sig ^= PERSISTENT_RAM_SIG; if (prz->buffer->sig == sig) { + if (buffer_size(prz) == 0) { + pr_debug("found existing empty buffer\n"); + return 0; + } + if (buffer_size(prz) > prz->buffer_size || - buffer_start(prz) > buffer_size(prz)) + buffer_start(prz) > buffer_size(prz)) { pr_info("found existing invalid buffer, size %zu, start %zu\n", buffer_size(prz), buffer_start(prz)); - else { + zap = true; + } else { pr_debug("found existing buffer, size %zu, start %zu\n", buffer_size(prz), buffer_start(prz)); persistent_ram_save_old(prz); - return 0; } } else { pr_debug("no valid data in buffer (sig = 0x%08x)\n", prz->buffer->sig); + prz->buffer->sig = sig; + zap = true; } - /* Rewind missing or invalid memory area. */ - prz->buffer->sig = sig; - persistent_ram_zap(prz); + /* Reset missing, invalid, or single-use memory area. */ + if (zap) + persistent_ram_zap(prz); return 0; } @@ -572,6 +593,12 @@ struct persistent_ram_zone *persistent_ram_new(phys_addr_t start, size_t size, if (ret) goto err; + pr_debug("attached %s 0x%zx@0x%llx: %zu header, %zu data, %zu ecc (%d/%d)\n", + prz->label, prz->size, (unsigned long long)prz->paddr, + sizeof(*prz->buffer), prz->buffer_size, + prz->size - sizeof(*prz->buffer) - prz->buffer_size, + prz->ecc_info.ecc_size, prz->ecc_info.block_size); + return prz; err: persistent_ram_free(prz); |