[PATCH] mtd-utils: nandtest: handle large nand devices

[Zhihao Cheng]

在 2023/8/10 16:20, Christian Wendt he/him 写道:
> [PATCH] mtd-utils: nandtest: handle large nand devices
> 
> Running nandtest on devices with sizes of 4Gb or more does not work, as
> the size returned in mtd_info_user is reported as 0 for 4Gb devices for
> example.
> 
> The patch uses sysfs to figure out the size of the nand device (as
> recommended in a comment in include/mtd/mtd-abi.h) and changes sizes
> and offsets to 64 bit values.
> 
> [From: Christian Wendt <cw at brainaid.de>]
> diff --git a/nand-utils/nandtest.c b/nand-utils/nandtest.c
> index 06dec25..e60428f 100644
> --- a/nand-utils/nandtest.c
> +++ b/nand-utils/nandtest.c
> @@ -8,6 +8,7 @@
>   #include <string.h>
>   #include <time.h>
>   #include <unistd.h>
> +#include <limits.h>
>   #include <sys/stat.h>
>   #include <sys/ioctl.h>
>   #include <sys/types.h>
> @@ -145,6 +146,26 @@ static int erase_and_write(loff_t ofs, unsigned 
> char *data, unsigned char *rbuf,
>   }
> 
> 
> +static uint64_t get_mem_size(const char* device)
> +{
> +       const char* p = strrchr(device, '/');
> +       char path[PATH_MAX];
> +       int fd;
> +
> +       snprintf(path, sizeof(path), "/sys/class/mtd/%s/size", p);
> +       fd = open(path, O_RDONLY);
> +       if (fd) {
> +               char buffer[32];
> +               ssize_t n = read(fd, buffer, sizeof(buffer));
> +               close(fd);
> +               if (n > 0) {
> +                       return strtoull(buffer, NULL, 0);
> +               }
> +       }

It's better to add error handling for open/read failures, otherwise 
'length' will be 0 if user doesn't pass '-l' parameter when open/read 
'/sys/class/mtd/mtdX/size' failed.

> +
> +       return 0;
> +}
> +
>   /*
>    * Main program
>    */
> @@ -156,8 +177,9 @@ int main(int argc, char **argv)
>          int nr_passes = 1;
>          int nr_reads = 4;
>          int keep_contents = 0;
> -       uint32_t offset = 0;
> -       uint32_t length = -1;
> +       uint64_t offset = 0;
> +       uint64_t length = -1;
> +       uint64_t mem_size = 0;
>          int error = 0;
> 
>          seed = time(NULL);
> @@ -238,29 +260,31 @@ int main(int argc, char **argv)
>                  exit(1);
>          }
> 
> +       mem_size = get_mem_size(argv[optind]);
> +
>          if (length == -1)
> -               length = meminfo.size;
> +               length = mem_size;
> 
>          if (offset % meminfo.erasesize) {
> -               fprintf(stderr, "Offset %x not multiple of erase size 
> %x\n",
> +               fprintf(stderr, "Offset %llx not multiple of erase size 
> %x\n",
>                          offset, meminfo.erasesize);
>                  exit(1);
>          }
>          if (length % meminfo.erasesize) {
> -               fprintf(stderr, "Length %x not multiple of erase size 
> %x\n",
> +               fprintf(stderr, "Length %llx not multiple of erase size 
> %x\n",
>                          length, meminfo.erasesize);
>                  exit(1);
>          }
> -       if (length + offset > meminfo.size) {
> -               fprintf(stderr, "Length %x + offset %x exceeds device 
> size %x\n",
> -                       length, offset, meminfo.size);
> +       if (length + offset > mem_size) {
> +               fprintf(stderr, "Length %llx + offset %llx exceeds 
> device size %llx\n",
> +                       length, offset, mem_size);
>                  exit(1);
>          }
> 
>          wbuf = malloc(meminfo.erasesize * 3);
>          if (!wbuf) {
>                  fprintf(stderr, "Could not allocate %d bytes for 
> buffer\n",
> -                       meminfo.erasesize * 2);
> +                       meminfo.erasesize * 3);
>                  exit(1);
>          }
>          rbuf = wbuf + meminfo.erasesize;
> 
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