Huge savedata driver refactor

bdk/libs/nx_savedata/cached_storage.c

@@ -0,0 +1,227 @@
+/*
+ * Copyright (c) 2019-2020 shchmue
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+/*
+ISC License
+
+hactool Copyright (c) 2018, SciresM
+
+Permission to use, copy, modify, and/or distribute this software for any
+purpose with or without fee is hereby granted, provided that the above
+copyright notice and this permission notice appear in all copies.
+
+THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+*/
+
+#include "cached_storage.h"
+
+#include <gfx_utils.h>
+#include <mem/heap.h>
+
+#include <string.h>
+
+static ALWAYS_INLINE cache_block_t *cache_block_init(cached_storage_ctx_t *ctx) {
+    cache_block_t *block = calloc(1, sizeof(cache_block_t));
+    block->buffer = malloc(ctx->block_size);
+    block->index = -1;
+    return block;
+}
+
+void save_cached_storage_init(cached_storage_ctx_t *ctx, substorage *base_storage, uint32_t block_size, uint32_t cache_size) {
+    memcpy(&ctx->base_storage, base_storage, sizeof(substorage));
+    ctx->block_size = block_size;
+    substorage_get_size(base_storage, &ctx->length);
+    ctx->cache_size = cache_size;
+
+    list_init(&ctx->blocks);
+    for (uint32_t i = 0; i < cache_size; i++) {
+        cache_block_t *block = cache_block_init(ctx);
+        list_append(&ctx->blocks, &block->link);
+    }
+}
+
+void save_cached_storage_init_from_sector_storage(cached_storage_ctx_t *ctx, sector_storage *base_storage, uint32_t cache_size) {
+    save_cached_storage_init(ctx, &base_storage->base_storage, base_storage->sector_size, cache_size);
+}
+
+static void cache_block_finalize(cache_block_t **block) {
+    free((*block)->buffer);
+    free(*block);
+}
+
+void save_cached_storage_finalize(cached_storage_ctx_t *ctx) {
+    LIST_FOREACH_SAFE(curr_block, &ctx->blocks) {
+        cache_block_t *block = CONTAINER_OF(curr_block, cache_block_t, link) ;
+        cache_block_finalize(&block);
+    }
+}
+
+static bool try_get_block_by_value(cached_storage_ctx_t *ctx, uint64_t index, cache_block_t **out_block) {
+    LIST_FOREACH_ENTRY(cache_block_t, block, &ctx->blocks, link) {
+        if (block->index == index) {
+            *out_block = block;
+            return true;
+        }
+    }
+    return false;
+}
+
+static bool flush_block(cached_storage_ctx_t *ctx, cache_block_t *block) {
+    if (!block->dirty)
+        return true;
+
+    uint64_t offset = block->index * ctx->block_size;
+    if (substorage_write(&ctx->base_storage, block->buffer, offset, block->length) != block->length) {
+        EPRINTF("Cached storage: Failed to write block!");
+        return false;
+    }
+    block->dirty = false;
+
+    return true;
+}
+
+static bool read_block(cached_storage_ctx_t *ctx, cache_block_t *block, uint64_t index) {
+    uint64_t offset = index * ctx->block_size;
+    uint32_t length = ctx->block_size;
+
+    if (ctx->length != -1)
+        length = (uint32_t)MIN(ctx->length - offset, length);
+
+    if (substorage_read(&ctx->base_storage, block->buffer, offset, length) != length) {
+        EPRINTF("Cached storage: Failed to read block!");
+        return false;
+    }
+    block->length = length;
+    block->index = index;
+    block->dirty = false;
+
+    return true;
+}
+
+static cache_block_t *get_block(cached_storage_ctx_t *ctx, uint64_t block_index) {
+    cache_block_t *block = NULL;
+    if (try_get_block_by_value(ctx, block_index, &block)) {
+        // Promote most recently used block to front of list if not already.
+        if (ctx->blocks.next != &block->link) {
+            list_remove(&block->link);
+            list_prepend(&ctx->blocks, &block->link);
+        }
+        return block;
+    }
+
+    // Get a pointer either to the least recently used block or to a newly allocated block if storage is empty.
+    bool block_is_new = false;
+    if (ctx->blocks.prev != &ctx->blocks) {
+        block = CONTAINER_OF(ctx->blocks.prev, cache_block_t, link);
+        if (!flush_block(ctx, block))
+            return NULL;
+
+        // Remove least recently used block from list.
+        list_remove(&block->link);
+    } else {
+        block = cache_block_init(ctx);
+        block_is_new = true;
+    }
+
+    if (!read_block(ctx, block, block_index)) {
+        if (block_is_new)
+            cache_block_finalize(&block);
+        return NULL;
+    }
+
+    list_prepend(&ctx->blocks, &block->link);
+
+    return block;
+}
+
+uint32_t save_cached_storage_read(cached_storage_ctx_t *ctx, void *buffer, uint64_t offset, uint64_t count) {
+    uint64_t remaining = count;
+    uint64_t in_offset = offset;
+    uint32_t out_offset = 0;
+
+    if (!is_range_valid(offset, count, ctx->length)) {
+        EPRINTF("Cached storage read out of range!");
+        return 0;
+    }
+
+    while (remaining) {
+        uint64_t block_index = in_offset / ctx->block_size;
+        uint32_t block_pos = (uint32_t)(in_offset % ctx->block_size);
+        cache_block_t *block = get_block(ctx,block_index);
+        if (!block) {
+            EPRINTFARGS("Cached storage read: Unable to get block\n at index %x", (uint32_t)block_index);
+            return 0;
+        }
+
+        uint32_t bytes_to_read = (uint32_t)MIN(remaining, ctx->block_size - block_pos);
+
+        memcpy((uint8_t *)buffer + out_offset, block->buffer + block_pos, bytes_to_read);
+
+        out_offset += bytes_to_read;
+        in_offset += bytes_to_read;
+        remaining -= bytes_to_read;
+    }
+
+    return out_offset;
+}
+
+uint32_t save_cached_storage_write(cached_storage_ctx_t *ctx, const void *buffer, uint64_t offset, uint64_t count) {
+    uint64_t remaining = count;
+    uint64_t in_offset = offset;
+    uint32_t out_offset = 0;
+
+    if (!is_range_valid(offset, count, ctx->length)) {
+        EPRINTF("Cached storage write out of range!");
+        return 0;
+    }
+
+    while (remaining) {
+        uint64_t block_index = in_offset / ctx->block_size;
+        uint32_t block_pos = (uint32_t)(in_offset % ctx->block_size);
+        cache_block_t *block = get_block(ctx,block_index);
+        if (!block) {
+            EPRINTFARGS("Cached storage write: Unable to get block\n at index %x", (uint32_t)block_index);
+            return 0;
+        }
+
+        uint32_t bytes_to_write = (uint32_t)MIN(remaining, ctx->block_size - block_pos);
+
+        memcpy(block->buffer + block_pos, (uint8_t *)buffer + out_offset, bytes_to_write);
+
+        block->dirty = true;
+
+        out_offset += bytes_to_write;
+        in_offset += bytes_to_write;
+        remaining -= bytes_to_write;
+    }
+
+    return out_offset;
+}
+
+bool save_cached_storage_flush(cached_storage_ctx_t *ctx) {
+    LIST_FOREACH_ENTRY(cache_block_t, block, &ctx->blocks, link) {
+        if (!flush_block(ctx, block))
+            return false;
+    }
+
+    return true;
+}