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-rw-r--r--drivers/staging/android/persistent_ram.c473
1 files changed, 0 insertions, 473 deletions
diff --git a/drivers/staging/android/persistent_ram.c b/drivers/staging/android/persistent_ram.c
deleted file mode 100644
index 8d8c1e33e0ff..000000000000
--- a/drivers/staging/android/persistent_ram.c
+++ /dev/null
@@ -1,473 +0,0 @@
-/*
- * Copyright (C) 2012 Google, Inc.
- *
- * This software is licensed under the terms of the GNU General Public
- * License version 2, as published by the Free Software Foundation, and
- * may be copied, distributed, and modified under those terms.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- */
-
-#include <linux/device.h>
-#include <linux/err.h>
-#include <linux/errno.h>
-#include <linux/kernel.h>
-#include <linux/init.h>
-#include <linux/io.h>
-#include <linux/list.h>
-#include <linux/memblock.h>
-#include <linux/rslib.h>
-#include <linux/slab.h>
-#include <linux/vmalloc.h>
-#include "persistent_ram.h"
-
-struct persistent_ram_buffer {
- uint32_t sig;
- atomic_t start;
- atomic_t size;
- uint8_t data[0];
-};
-
-#define PERSISTENT_RAM_SIG (0x43474244) /* DBGC */
-
-static __initdata LIST_HEAD(persistent_ram_list);
-
-static inline size_t buffer_size(struct persistent_ram_zone *prz)
-{
- return atomic_read(&prz->buffer->size);
-}
-
-static inline size_t buffer_start(struct persistent_ram_zone *prz)
-{
- return atomic_read(&prz->buffer->start);
-}
-
-/* increase and wrap the start pointer, returning the old value */
-static inline size_t buffer_start_add(struct persistent_ram_zone *prz, size_t a)
-{
- int old;
- int new;
-
- do {
- old = atomic_read(&prz->buffer->start);
- new = old + a;
- while (unlikely(new > prz->buffer_size))
- new -= prz->buffer_size;
- } while (atomic_cmpxchg(&prz->buffer->start, old, new) != old);
-
- return old;
-}
-
-/* increase the size counter until it hits the max size */
-static inline void buffer_size_add(struct persistent_ram_zone *prz, size_t a)
-{
- size_t old;
- size_t new;
-
- if (atomic_read(&prz->buffer->size) == prz->buffer_size)
- return;
-
- do {
- old = atomic_read(&prz->buffer->size);
- new = old + a;
- if (new > prz->buffer_size)
- new = prz->buffer_size;
- } while (atomic_cmpxchg(&prz->buffer->size, old, new) != old);
-}
-
-/* increase the size counter, retuning an error if it hits the max size */
-static inline ssize_t buffer_size_add_clamp(struct persistent_ram_zone *prz,
- size_t a)
-{
- size_t old;
- size_t new;
-
- do {
- old = atomic_read(&prz->buffer->size);
- new = old + a;
- if (new > prz->buffer_size)
- return -ENOMEM;
- } while (atomic_cmpxchg(&prz->buffer->size, old, new) != old);
-
- return 0;
-}
-
-static void notrace persistent_ram_encode_rs8(struct persistent_ram_zone *prz,
- uint8_t *data, size_t len, uint8_t *ecc)
-{
- int i;
- 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 < prz->ecc_size; i++)
- ecc[i] = par[i];
-}
-
-static int persistent_ram_decode_rs8(struct persistent_ram_zone *prz,
- void *data, size_t len, uint8_t *ecc)
-{
- int 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);
-}
-
-static void notrace persistent_ram_update_ecc(struct persistent_ram_zone *prz,
- unsigned int start, unsigned int count)
-{
- struct persistent_ram_buffer *buffer = prz->buffer;
- uint8_t *buffer_end = buffer->data + prz->buffer_size;
- uint8_t *block;
- uint8_t *par;
- 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 + (start & ~(ecc_block_size - 1));
- par = prz->par_buffer + (start / ecc_block_size) * prz->ecc_size;
-
- do {
- 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;
- } while (block < buffer->data + start + count);
-}
-
-static void persistent_ram_update_header_ecc(struct persistent_ram_zone *prz)
-{
- struct persistent_ram_buffer *buffer = prz->buffer;
-
- if (!prz->ecc)
- return;
-
- persistent_ram_encode_rs8(prz, (uint8_t *)buffer, sizeof(*buffer),
- prz->par_header);
-}
-
-static void persistent_ram_ecc_old(struct persistent_ram_zone *prz)
-{
- struct persistent_ram_buffer *buffer = prz->buffer;
- uint8_t *block;
- uint8_t *par;
-
- if (!prz->ecc)
- return;
-
- block = buffer->data;
- par = prz->par_buffer;
- while (block < buffer->data + buffer_size(prz)) {
- int numerr;
- 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) {
- pr_devel("persistent_ram: error in block %p, %d\n",
- block, numerr);
- prz->corrected_bytes += numerr;
- } else if (numerr < 0) {
- pr_devel("persistent_ram: uncorrectable error in block %p\n",
- block);
- prz->bad_blocks++;
- }
- 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;
- }
-
- 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 notrace persistent_ram_update(struct persistent_ram_zone *prz,
- const void *s, unsigned int start, unsigned int count)
-{
- struct persistent_ram_buffer *buffer = prz->buffer;
- memcpy(buffer->data + start, s, count);
- persistent_ram_update_ecc(prz, start, count);
-}
-
-static void __init
-persistent_ram_save_old(struct persistent_ram_zone *prz)
-{
- struct persistent_ram_buffer *buffer = prz->buffer;
- size_t size = buffer_size(prz);
- size_t start = buffer_start(prz);
- char *dest;
-
- persistent_ram_ecc_old(prz);
-
- dest = kmalloc(size, GFP_KERNEL);
- if (dest == NULL) {
- pr_err("persistent_ram: failed to allocate buffer\n");
- return;
- }
-
- prz->old_log = dest;
- prz->old_log_size = size;
- memcpy(prz->old_log, &buffer->data[start], size - start);
- memcpy(prz->old_log + size - start, &buffer->data[0], start);
-}
-
-int notrace persistent_ram_write(struct persistent_ram_zone *prz,
- const void *s, unsigned int count)
-{
- int rem;
- int c = count;
- size_t start;
-
- if (unlikely(c > prz->buffer_size)) {
- s += c - prz->buffer_size;
- c = prz->buffer_size;
- }
-
- buffer_size_add_clamp(prz, c);
-
- start = buffer_start_add(prz, c);
-
- rem = prz->buffer_size - start;
- if (unlikely(rem < c)) {
- persistent_ram_update(prz, s, start, rem);
- s += rem;
- c -= rem;
- start = 0;
- }
- persistent_ram_update(prz, s, start, c);
-
- persistent_ram_update_header_ecc(prz);
-
- return count;
-}
-
-size_t persistent_ram_old_size(struct persistent_ram_zone *prz)
-{
- return prz->old_log_size;
-}
-
-void *persistent_ram_old(struct persistent_ram_zone *prz)
-{
- return prz->old_log;
-}
-
-void persistent_ram_free_old(struct persistent_ram_zone *prz)
-{
- kfree(prz->old_log);
- prz->old_log = NULL;
- prz->old_log_size = 0;
-}
-
-static int persistent_ram_buffer_map(phys_addr_t start, phys_addr_t size,
- struct persistent_ram_zone *prz)
-{
- struct page **pages;
- phys_addr_t page_start;
- unsigned int page_count;
- pgprot_t prot;
- unsigned int i;
-
- page_start = start - offset_in_page(start);
- page_count = DIV_ROUND_UP(size + offset_in_page(start), PAGE_SIZE);
-
- prot = pgprot_noncached(PAGE_KERNEL);
-
- pages = kmalloc(sizeof(struct page *) * page_count, GFP_KERNEL);
- if (!pages) {
- pr_err("%s: Failed to allocate array for %u pages\n", __func__,
- page_count);
- return -ENOMEM;
- }
-
- for (i = 0; i < page_count; i++) {
- phys_addr_t addr = page_start + i * PAGE_SIZE;
- pages[i] = pfn_to_page(addr >> PAGE_SHIFT);
- }
- prz->vaddr = vmap(pages, page_count, VM_MAP, prot);
- kfree(pages);
- if (!prz->vaddr) {
- pr_err("%s: Failed to map %u pages\n", __func__, page_count);
- return -ENOMEM;
- }
-
- prz->buffer = prz->vaddr + offset_in_page(start);
- prz->buffer_size = size - sizeof(struct persistent_ram_buffer);
-
- return 0;
-}
-
-static int __init persistent_ram_buffer_init(const char *name,
- struct persistent_ram_zone *prz)
-{
- int i;
- struct persistent_ram *ram;
- struct persistent_ram_descriptor *desc;
- phys_addr_t start;
-
- list_for_each_entry(ram, &persistent_ram_list, node) {
- start = ram->start;
- for (i = 0; i < ram->num_descs; i++) {
- desc = &ram->descs[i];
- if (!strcmp(desc->name, name))
- return persistent_ram_buffer_map(start,
- desc->size, prz);
- start += desc->size;
- }
- }
-
- return -EINVAL;
-}
-
-static __init
-struct persistent_ram_zone *__persistent_ram_init(struct device *dev, bool ecc)
-{
- struct persistent_ram_zone *prz;
- int ret = -ENOMEM;
-
- prz = kzalloc(sizeof(struct persistent_ram_zone), GFP_KERNEL);
- if (!prz) {
- pr_err("persistent_ram: failed to allocate persistent ram zone\n");
- goto err;
- }
-
- INIT_LIST_HEAD(&prz->node);
-
- ret = persistent_ram_buffer_init(dev_name(dev), prz);
- if (ret) {
- pr_err("persistent_ram: failed to initialize buffer\n");
- goto err;
- }
-
- prz->ecc = ecc;
- ret = persistent_ram_init_ecc(prz, prz->buffer_size);
- if (ret)
- goto err;
-
- if (prz->buffer->sig == PERSISTENT_RAM_SIG) {
- if (buffer_size(prz) > prz->buffer_size ||
- buffer_start(prz) > buffer_size(prz))
- pr_info("persistent_ram: found existing invalid buffer,"
- " size %ld, start %ld\n",
- buffer_size(prz), buffer_start(prz));
- else {
- pr_info("persistent_ram: found existing buffer,"
- " size %ld, start %ld\n",
- buffer_size(prz), buffer_start(prz));
- persistent_ram_save_old(prz);
- }
- } else {
- pr_info("persistent_ram: no valid data in buffer"
- " (sig = 0x%08x)\n", prz->buffer->sig);
- }
-
- prz->buffer->sig = PERSISTENT_RAM_SIG;
- atomic_set(&prz->buffer->start, 0);
- atomic_set(&prz->buffer->size, 0);
-
- return prz;
-err:
- kfree(prz);
- return ERR_PTR(ret);
-}
-
-struct persistent_ram_zone * __init
-persistent_ram_init_ringbuffer(struct device *dev, bool ecc)
-{
- return __persistent_ram_init(dev, ecc);
-}
-
-int __init persistent_ram_early_init(struct persistent_ram *ram)
-{
- int ret;
-
- ret = memblock_reserve(ram->start, ram->size);
- if (ret) {
- pr_err("Failed to reserve persistent memory from %08lx-%08lx\n",
- (long)ram->start, (long)(ram->start + ram->size - 1));
- return ret;
- }
-
- list_add_tail(&ram->node, &persistent_ram_list);
-
- pr_info("Initialized persistent memory from %08lx-%08lx\n",
- (long)ram->start, (long)(ram->start + ram->size - 1));
-
- return 0;
-}