Add nand driver that works with a nand simulator

[yaffs2.git] / direct / test-framework / nandstore_file.c

diff --git a/direct/test-framework/nandstore_file.c b/direct/test-framework/nandstore_file.c
new file mode 100644 (file)
index 0000000..1b9b70b
--- /dev/null
+++ b/direct/test-framework/nandstore_file.c
@@ -0,0 +1,188 @@
+/*
+ * YAFFS: Yet Another Flash File System. A NAND-flash specific file system.
+ *
+ * Copyright (C) 2010-2011 Aleph One Ltd.
+ *
+ * Created by Charles Manning <charles@aleph1.co.uk>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+/*
+ * Nand simulator modelled on a Samsung K9K2G08U0A 8-bit
+ *
+ *  Need to implement basic commands first:
+ *  Status
+ *  Reset
+ *  Read
+ *  Random read (ie set read position within current page)
+ *  Write
+ *  Erase
+ */
+
+#include "nandstore_file.h"
+#include "nand_store.h"
+#include <stdint.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <string.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+extern int random_seed;
+extern int simulate_power_failure;
+static int remaining_ops;
+static int nops_so_far;
+
+struct nandstore_file_private {
+       char backing_file[500];
+       int handle;
+       unsigned char * buffer;
+       int buff_size;
+};
+
+static void maybe_power_fail(unsigned int nand_chunk, int fail_point)
+{
+
+   nops_so_far++;
+
+   remaining_ops--;
+   if(simulate_power_failure &&
+      remaining_ops < 1){
+       printf("Simulated power failure after %d operations\n",nops_so_far);
+       printf("  power failed on nand_chunk %d, at fail point %d\n",
+                               nand_chunk, fail_point);
+       exit(0);
+  }
+}
+
+static void power_fail_init(void)
+{
+       remaining_ops = (rand() % 1000) * 5;
+}
+
+static int nandstore_file_store(struct nand_store *this, int page,
+                               const unsigned char * buffer)
+{
+       struct nandstore_file_private *nsfp =
+               (struct nandstore_file_private *)this->private_data;
+       int pos = nsfp->buff_size * page;
+       int i;
+
+       maybe_power_fail(page, __LINE__);
+
+       lseek(nsfp->handle, pos, SEEK_SET);
+       read(nsfp->handle, nsfp->buffer, nsfp->buff_size);
+       for(i = 0; i < nsfp->buff_size; i++)
+               nsfp->buffer[i] &= buffer[i];
+       lseek(nsfp->handle, pos, SEEK_SET);
+       write(nsfp->handle, nsfp->buffer, nsfp->buff_size);
+
+       maybe_power_fail(page, __LINE__);
+
+       return 0;
+}
+
+static int nandstore_file_retrieve(struct nand_store *this, int page,
+                               unsigned char * buffer)
+{
+       struct nandstore_file_private *nsfp =
+               (struct nandstore_file_private *)this->private_data;
+
+       lseek(nsfp->handle, nsfp->buff_size * page, SEEK_SET);
+       read(nsfp->handle, buffer, nsfp->buff_size);
+       return 0;
+}
+static int nandstore_file_erase(struct nand_store *this, int page)
+{
+       int block = page / this->pages_per_block;
+       struct nandstore_file_private *nsfp =
+               (struct nandstore_file_private *)this->private_data;
+       int i;
+
+       maybe_power_fail(page, __LINE__);
+
+       lseek(nsfp->handle,
+               block * nsfp->buff_size * this->pages_per_block, SEEK_SET);
+       memset(nsfp->buffer, 0xff, nsfp->buff_size);
+       for(i = 0; i < this->pages_per_block; i++)
+               write(nsfp->handle, nsfp->buffer, nsfp->buff_size);
+       return 0;
+}
+
+static int nandstore_file_shutdown(struct nand_store *this)
+{
+       struct nandstore_file_private *nsfp =
+               (struct nandstore_file_private *)this->private_data;
+       close(nsfp->handle);
+       nsfp->handle = -1;
+       return 0;
+}
+
+struct nand_store *
+nandstore_file_init(const char *fname,
+                               int blocks,
+                               int pages_per_block,
+                               int data_bytes_per_page,
+                               int spare_bytes_per_page)
+{
+       int fsize;
+       int nbytes;
+       int i;
+       struct nand_store *ns;
+       struct nandstore_file_private *nsfp;
+       unsigned char *buffer;
+       int buff_size = data_bytes_per_page + spare_bytes_per_page;
+
+       ns = malloc(sizeof(struct nand_store));
+       nsfp = malloc(sizeof(struct nandstore_file_private));
+       buffer = malloc(buff_size);
+
+
+       if (!ns || !nsfp || !buffer) {
+               free(ns);
+               free(nsfp);
+               free(buffer);
+               return NULL;
+       }
+
+       memset(ns, 0, sizeof(*ns));
+       memset(nsfp, 0, sizeof(*nsfp));
+       nsfp->buffer = buffer;
+       nsfp->buff_size = buff_size;
+       ns->private_data = nsfp;
+
+       ns->store = nandstore_file_store;
+       ns->retrieve = nandstore_file_retrieve;
+       ns->erase = nandstore_file_erase;
+       ns->shutdown = nandstore_file_shutdown;
+
+       ns->blocks = blocks;
+       ns->pages_per_block = pages_per_block;
+       ns->data_bytes_per_page = data_bytes_per_page;
+       ns->spare_bytes_per_page = spare_bytes_per_page;
+
+       strncpy(nsfp->backing_file, fname, sizeof(nsfp->backing_file));
+
+       nsfp->handle = open(nsfp->backing_file, O_RDWR | O_CREAT);
+       if(nsfp->handle >=0){
+               fsize = lseek(nsfp->handle,0,SEEK_END);
+               nbytes = ns->blocks * ns->pages_per_block *
+                       (ns->data_bytes_per_page + ns->spare_bytes_per_page);
+               if (fsize != nbytes) {
+                       printf("Initialising backing file.\n");
+                       ftruncate(nsfp->handle,0);
+                       for(i = 0; i < ns->blocks; i++)
+                               nandstore_file_erase(ns,
+                                       i * ns->pages_per_block);
+               }
+       }
+
+       power_fail_init();
+
+       return ns;
+
+
+}
+