yaffs2 checkpointing: Add further checkpoint data sanity checking
authorCharles Manning <cdhmanning@gmail.com>
Mon, 21 May 2012 22:28:11 +0000 (10:28 +1200)
committerCharles Manning <cdhmanning@gmail.com>
Mon, 21 May 2012 22:28:11 +0000 (10:28 +1200)
Add a header to each chunk of checkpoint data to verify that the
checkpoint data is correct.

Signed-off-by: Charles Manning <cdhmanning@gmail.com>
direct/basic-test/dtest.c
yaffs_checkptrw.c
yaffs_guts.h

index e3abe0f..153d274 100644 (file)
@@ -2791,7 +2791,9 @@ void max_files_test(const char *mountpt)
                result = yaffs_close(h);
        }
 
-       h =yaffs_open(hn,O_RDWR,0);
+       yaffs_unmount(mountpt);
+
+       //h =yaffs_open(hn,O_RDWR,0);
 
 }
 void case_insensitive_test(const char *mountpt)
@@ -3147,12 +3149,12 @@ int main(int argc, char *argv[])
         // link_follow_test("/yaffs2");
         //basic_utime_test("/yaffs2");
 
-        //max_files_test("/yaffs2");
+       max_files_test("/yaffs2");
 
         //start_twice("/yaffs2");
 
         //large_file_test("/yaffs2");
-        readdir_test("/yaffs2");
+        //readdir_test("/yaffs2");
 
         //basic_utime_test("/yaffs2");
         //case_insensitive_test("/yaffs2");
index 918c382..d897044 100644 (file)
 #include "yaffs_checkptrw.h"
 #include "yaffs_getblockinfo.h"
 
+struct yaffs_checkpt_chunk_hdr {
+       int version;
+       int seq;
+       u32 sum;
+       u32 xor;
+} ;
+
+static void yaffs2_checkpt_init_chunk_hdr(struct yaffs_dev *dev)
+{
+       struct yaffs_checkpt_chunk_hdr hdr;
+
+       hdr.version = YAFFS_CHECKPOINT_VERSION;
+       hdr.seq = dev->checkpt_page_seq;
+       hdr.sum = dev->checkpt_sum;
+       hdr.xor = dev->checkpt_xor;
+
+       dev->checkpt_byte_offs = sizeof(hdr);
+
+       memcpy(dev->checkpt_buffer, &hdr, sizeof(hdr));
+}
+
+static int yaffs2_checkpt_check_chunk_hdr(struct yaffs_dev *dev)
+{
+       struct yaffs_checkpt_chunk_hdr hdr;
+
+       memcpy(&hdr, dev->checkpt_buffer, sizeof(hdr));
+
+       dev->checkpt_byte_offs = sizeof(hdr);
+
+       return hdr.version == YAFFS_CHECKPOINT_VERSION &&
+               hdr.seq == dev->checkpt_page_seq &&
+               hdr.sum == dev->checkpt_sum &&
+               hdr.xor == dev->checkpt_xor;
+}
+
 static int yaffs2_checkpt_space_ok(struct yaffs_dev *dev)
 {
        int blocks_avail = dev->n_erased_blocks - dev->param.n_reserved_blocks;
@@ -171,13 +206,13 @@ int yaffs2_checkpt_open(struct yaffs_dev *dev, int writing)
        dev->checkpt_cur_chunk = -1;
        dev->checkpt_next_block = dev->internal_start_block;
 
-       /* Erase all the blocks in the checkpoint area */
        if (writing) {
                memset(dev->checkpt_buffer, 0, dev->data_bytes_per_chunk);
-               dev->checkpt_byte_offs = 0;
+               yaffs2_checkpt_init_chunk_hdr(dev);
                return yaffs_checkpt_erase(dev);
        }
 
+       /* Opening for a read */
        /* Set to a value that will kick off a read */
        dev->checkpt_byte_offs = dev->data_bytes_per_chunk;
        /* A checkpoint block list of 1 checkpoint block per 16 block is
@@ -249,7 +284,6 @@ static int yaffs2_checkpt_flush_buffer(struct yaffs_dev *dev)
 
        dev->param.write_chunk_tags_fn(dev, realigned_chunk,
                                       dev->checkpt_buffer, &tags);
-       dev->checkpt_byte_offs = 0;
        dev->checkpt_page_seq++;
        dev->checkpt_cur_chunk++;
        if (dev->checkpt_cur_chunk >= dev->param.chunks_per_block) {
@@ -258,6 +292,9 @@ static int yaffs2_checkpt_flush_buffer(struct yaffs_dev *dev)
        }
        memset(dev->checkpt_buffer, 0, dev->data_bytes_per_chunk);
 
+       yaffs2_checkpt_init_chunk_hdr(dev);
+
+
        return 1;
 }
 
@@ -340,14 +377,18 @@ int yaffs2_checkpt_rd(struct yaffs_dev *dev, void *data, int n_bytes)
                                ok = 0;
                                break;
                        }
+                       if(!yaffs2_checkpt_check_chunk_hdr(dev)) {
+                               ok = 0;
+                               break;
+                       }
 
-                       dev->checkpt_byte_offs = 0;
                        dev->checkpt_page_seq++;
                        dev->checkpt_cur_chunk++;
 
                        if (dev->checkpt_cur_chunk >=
                                        dev->param.chunks_per_block)
                                dev->checkpt_cur_block = -1;
+
                }
 
                *data_bytes = dev->checkpt_buffer[dev->checkpt_byte_offs];
@@ -367,7 +408,8 @@ int yaffs_checkpt_close(struct yaffs_dev *dev)
        int i;
 
        if (dev->checkpt_open_write) {
-               if (dev->checkpt_byte_offs != 0)
+               if (dev->checkpt_byte_offs !=
+                       sizeof(sizeof(struct yaffs_checkpt_chunk_hdr)))
                        yaffs2_checkpt_flush_buffer(dev);
        } else if (dev->checkpt_block_list) {
                for (i = 0;
index e3558c5..d320070 100644 (file)
@@ -77,7 +77,7 @@
 
 /* Binary data version stamps */
 #define YAFFS_SUMMARY_VERSION          1
-#define YAFFS_CHECKPOINT_VERSION       6
+#define YAFFS_CHECKPOINT_VERSION       7
 
 #ifdef CONFIG_YAFFS_UNICODE
 #define YAFFS_MAX_NAME_LENGTH          127