diff options
author | Colin Cross <ccross@android.com> | 2012-03-07 17:34:33 -0800 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2012-03-08 09:36:08 -0800 |
commit | 9cc05ad97c5728aaf4db94490daf41f8958b5aee (patch) | |
tree | 704711c8ac8c776b0baa9cc2e3bb6491a5918520 /drivers/staging/android/persistent_ram.c | |
parent | c672528aec4a1cf6f3df7a6022e6823a20b20f8e (diff) |
staging: android: persistent_ram: refactor ecc support
Remove CONFIG_ANDROID_RAM_CONSOLE_ERROR_CORRECTION and related
#ifdefs. Also allow persistent ram zones without ecc enabled.
For some use cases, like the data portion of the upcoming
persistent_vars patches, or a persistent ftrace ringbuffer,
ecc on every update is too expensive.
CC: Greg KH <gregkh@linuxfoundation.org>
CC: Android Kernel Team <kernel-team@android.com>
Signed-off-by: Colin Cross <ccross@android.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/staging/android/persistent_ram.c')
-rw-r--r-- | drivers/staging/android/persistent_ram.c | 239 |
1 files changed, 130 insertions, 109 deletions
diff --git a/drivers/staging/android/persistent_ram.c b/drivers/staging/android/persistent_ram.c index d0f46661de46..35c57a05f16d 100644 --- a/drivers/staging/android/persistent_ram.c +++ b/drivers/staging/android/persistent_ram.c @@ -16,13 +16,10 @@ #include <linux/kernel.h> #include <linux/init.h> #include <linux/io.h> +#include <linux/rslib.h> #include <linux/slab.h> #include "persistent_ram.h" -#ifdef CONFIG_ANDROID_RAM_CONSOLE_ERROR_CORRECTION -#include <linux/rslib.h> -#endif - struct persistent_ram_buffer { uint32_t sig; uint32_t start; @@ -34,21 +31,16 @@ struct persistent_ram_buffer { static LIST_HEAD(zone_list); -#define ECC_BLOCK_SIZE CONFIG_ANDROID_RAM_CONSOLE_ERROR_CORRECTION_DATA_SIZE -#define ECC_SIZE CONFIG_ANDROID_RAM_CONSOLE_ERROR_CORRECTION_ECC_SIZE -#define ECC_SYMSIZE CONFIG_ANDROID_RAM_CONSOLE_ERROR_CORRECTION_SYMBOL_SIZE -#define ECC_POLY CONFIG_ANDROID_RAM_CONSOLE_ERROR_CORRECTION_POLYNOMIAL - -#ifdef CONFIG_ANDROID_RAM_CONSOLE_ERROR_CORRECTION static void persistent_ram_encode_rs8(struct persistent_ram_zone *prz, uint8_t *data, size_t len, uint8_t *ecc) { int i; - uint16_t par[ECC_SIZE]; + uint16_t par[prz->ecc_size]; + /* Initialize the parity buffer */ memset(par, 0, sizeof(par)); encode_rs8(prz->rs_decoder, data, len, par, 0); - for (i = 0; i < ECC_SIZE; i++) + for (i = 0; i < prz->ecc_size; i++) ecc[i] = par[i]; } @@ -56,84 +48,167 @@ static int persistent_ram_decode_rs8(struct persistent_ram_zone *prz, void *data, size_t len, uint8_t *ecc) { int i; - uint16_t par[ECC_SIZE]; - for (i = 0; i < ECC_SIZE; i++) + uint16_t par[prz->ecc_size]; + + for (i = 0; i < prz->ecc_size; i++) par[i] = ecc[i]; return decode_rs8(prz->rs_decoder, data, par, len, NULL, 0, NULL, 0, NULL); } -#endif -static void persistent_ram_update(struct persistent_ram_zone *prz, - const void *s, unsigned int count) +static void persistent_ram_update_ecc(struct persistent_ram_zone *prz, + unsigned int count) { struct persistent_ram_buffer *buffer = prz->buffer; -#ifdef CONFIG_ANDROID_RAM_CONSOLE_ERROR_CORRECTION uint8_t *buffer_end = buffer->data + prz->buffer_size; uint8_t *block; uint8_t *par; - int size = ECC_BLOCK_SIZE; -#endif - memcpy(buffer->data + buffer->start, s, count); -#ifdef CONFIG_ANDROID_RAM_CONSOLE_ERROR_CORRECTION - block = buffer->data + (buffer->start & ~(ECC_BLOCK_SIZE - 1)); + int ecc_block_size = prz->ecc_block_size; + int ecc_size = prz->ecc_size; + int size = prz->ecc_block_size; + + if (!prz->ecc) + return; + + block = buffer->data + (buffer->start & ~(ecc_block_size - 1)); par = prz->par_buffer + - (buffer->start / ECC_BLOCK_SIZE) * ECC_SIZE; + (buffer->start / ecc_block_size) * prz->ecc_size; do { - if (block + ECC_BLOCK_SIZE > buffer_end) + if (block + ecc_block_size > buffer_end) size = buffer_end - block; persistent_ram_encode_rs8(prz, block, size, par); - block += ECC_BLOCK_SIZE; - par += ECC_SIZE; + block += ecc_block_size; + par += ecc_size; } while (block < buffer->data + buffer->start + count); -#endif } -static void persistent_ram_update_header(struct persistent_ram_zone *prz) +static void persistent_ram_update_header_ecc(struct persistent_ram_zone *prz) { -#ifdef CONFIG_ANDROID_RAM_CONSOLE_ERROR_CORRECTION struct persistent_ram_buffer *buffer = prz->buffer; + if (!prz->ecc) + return; + persistent_ram_encode_rs8(prz, (uint8_t *)buffer, sizeof(*buffer), prz->par_header); -#endif } -static void __init -persistent_ram_save_old(struct persistent_ram_zone *prz) +static void persistent_ram_ecc_old(struct persistent_ram_zone *prz) { struct persistent_ram_buffer *buffer = prz->buffer; - size_t old_log_size = buffer->size; - char *dest; -#ifdef CONFIG_ANDROID_RAM_CONSOLE_ERROR_CORRECTION uint8_t *block; uint8_t *par; + if (!prz->ecc) + return; + block = buffer->data; par = prz->par_buffer; while (block < buffer->data + buffer->size) { int numerr; - int size = ECC_BLOCK_SIZE; + int size = prz->ecc_block_size; if (block + size > buffer->data + prz->buffer_size) size = buffer->data + prz->buffer_size - block; numerr = persistent_ram_decode_rs8(prz, block, size, par); if (numerr > 0) { -#if 0 - pr_info("persistent_ram: error in block %p, %d\n", + pr_devel("persistent_ram: error in block %p, %d\n", block, numerr); -#endif prz->corrected_bytes += numerr; } else if (numerr < 0) { -#if 0 - pr_info("persistent_ram: uncorrectable error in block %p\n", + pr_devel("persistent_ram: uncorrectable error in block %p\n", block); -#endif prz->bad_blocks++; } - block += ECC_BLOCK_SIZE; - par += ECC_SIZE; + block += prz->ecc_block_size; + par += prz->ecc_size; + } +} + +static int persistent_ram_init_ecc(struct persistent_ram_zone *prz, + size_t buffer_size) +{ + int numerr; + struct persistent_ram_buffer *buffer = prz->buffer; + int ecc_blocks; + + if (!prz->ecc) + return 0; + + prz->ecc_block_size = 128; + prz->ecc_size = 16; + prz->ecc_symsize = 8; + prz->ecc_poly = 0x11d; + + ecc_blocks = DIV_ROUND_UP(prz->buffer_size, prz->ecc_block_size); + prz->buffer_size -= (ecc_blocks + 1) * prz->ecc_size; + + if (prz->buffer_size > buffer_size) { + pr_err("persistent_ram: invalid size %zu, non-ecc datasize %zu\n", + buffer_size, prz->buffer_size); + return -EINVAL; + } + + prz->par_buffer = buffer->data + prz->buffer_size; + prz->par_header = prz->par_buffer + ecc_blocks * prz->ecc_size; + + /* + * first consecutive root is 0 + * primitive element to generate roots = 1 + */ + prz->rs_decoder = init_rs(prz->ecc_symsize, prz->ecc_poly, 0, 1, + prz->ecc_size); + if (prz->rs_decoder == NULL) { + pr_info("persistent_ram: init_rs failed\n"); + return -EINVAL; } -#endif + + prz->corrected_bytes = 0; + prz->bad_blocks = 0; + + numerr = persistent_ram_decode_rs8(prz, buffer, sizeof(*buffer), + prz->par_header); + if (numerr > 0) { + pr_info("persistent_ram: error in header, %d\n", numerr); + prz->corrected_bytes += numerr; + } else if (numerr < 0) { + pr_info("persistent_ram: uncorrectable error in header\n"); + prz->bad_blocks++; + } + + return 0; +} + +ssize_t persistent_ram_ecc_string(struct persistent_ram_zone *prz, + char *str, size_t len) +{ + ssize_t ret; + + if (prz->corrected_bytes || prz->bad_blocks) + ret = snprintf(str, len, "" + "\n%d Corrected bytes, %d unrecoverable blocks\n", + prz->corrected_bytes, prz->bad_blocks); + else + ret = snprintf(str, len, "\nNo errors detected\n"); + + return ret; +} + +static void persistent_ram_update(struct persistent_ram_zone *prz, + const void *s, unsigned int count) +{ + struct persistent_ram_buffer *buffer = prz->buffer; + memcpy(buffer->data + buffer->start, s, count); + persistent_ram_update_ecc(prz, count); +} + +static void __init +persistent_ram_save_old(struct persistent_ram_zone *prz) +{ + struct persistent_ram_buffer *buffer = prz->buffer; + size_t old_log_size = buffer->size; + char *dest; + + persistent_ram_ecc_old(prz); dest = kmalloc(old_log_size, GFP_KERNEL); if (dest == NULL) { @@ -173,30 +248,11 @@ int persistent_ram_write(struct persistent_ram_zone *prz, buffer->start += c; if (buffer->size < prz->buffer_size) buffer->size += c; - persistent_ram_update_header(prz); + persistent_ram_update_header_ecc(prz); return count; } -ssize_t persistent_ram_ecc_string(struct persistent_ram_zone *prz, - char *str, size_t len) -{ -#ifdef CONFIG_ANDROID_RAM_CONSOLE_ERROR_CORRECTION - ssize_t ret; - - if (prz->corrected_bytes || prz->bad_blocks) - ret = snprintf(str, len, "" - "\n%d Corrected bytes, %d unrecoverable blocks\n", - prz->corrected_bytes, prz->bad_blocks); - else - ret = snprintf(str, len, "\nNo errors detected\n"); - - return ret; -#else - return 0; -#endif -} - size_t persistent_ram_old_size(struct persistent_ram_zone *prz) { return prz->old_log_size; @@ -215,12 +271,10 @@ void persistent_ram_free_old(struct persistent_ram_zone *prz) } static int __init __persistent_ram_init(struct persistent_ram_zone *prz, - void __iomem *mem, size_t buffer_size) + void __iomem *mem, size_t buffer_size, bool ecc) { struct persistent_ram_buffer *buffer = mem; -#ifdef CONFIG_ANDROID_RAM_CONSOLE_ERROR_CORRECTION - int numerr; -#endif + int ret; INIT_LIST_HEAD(&prz->node); @@ -233,43 +287,10 @@ static int __init __persistent_ram_init(struct persistent_ram_zone *prz, return -EINVAL; } -#ifdef CONFIG_ANDROID_RAM_CONSOLE_ERROR_CORRECTION - prz->buffer_size -= (DIV_ROUND_UP(prz->buffer_size, - ECC_BLOCK_SIZE) + 1) * ECC_SIZE; - - if (prz->buffer_size > buffer_size) { - pr_err("persistent_ram: buffer %p, invalid size %zu, non-ecc datasize %zu\n", - buffer, buffer_size, prz->buffer_size); - return -EINVAL; - } - - prz->par_buffer = buffer->data + prz->buffer_size; - prz->par_header = prz->par_buffer + - DIV_ROUND_UP(prz->buffer_size, ECC_BLOCK_SIZE) * ECC_SIZE; - - - /* first consecutive root is 0 - * primitive element to generate roots = 1 - */ - prz->rs_decoder = init_rs(ECC_SYMSIZE, ECC_POLY, 0, 1, ECC_SIZE); - if (prz->rs_decoder == NULL) { - pr_info("persistent_ram: init_rs failed\n"); - return -EINVAL; - } - - prz->corrected_bytes = 0; - prz->bad_blocks = 0; - - numerr = persistent_ram_decode_rs8(prz, buffer, sizeof(*buffer), - prz->par_header); - if (numerr > 0) { - pr_info("persistent_ram: error in header, %d\n", numerr); - prz->corrected_bytes += numerr; - } else if (numerr < 0) { - pr_info("persistent_ram: uncorrectable error in header\n"); - prz->bad_blocks++; - } -#endif + prz->ecc = ecc; + ret = persistent_ram_init_ecc(prz, buffer_size); + if (ret) + return ret; if (buffer->sig == PERSISTENT_RAM_SIG) { if (buffer->size > prz->buffer_size @@ -296,7 +317,7 @@ static int __init __persistent_ram_init(struct persistent_ram_zone *prz, } int __init persistent_ram_init_ringbuffer(struct persistent_ram_zone *prz, - void __iomem *mem, size_t buffer_size) + void __iomem *mem, size_t buffer_size, bool ecc) { - return __persistent_ram_init(prz, mem, buffer_size); + return __persistent_ram_init(prz, mem, buffer_size, true); } |