debugfs: fixup the hard-coded buffer length in dump_file

Allocate the block buffer in dump_file() instead of assuming that the
block size is no more than 8k.

CC: George Spelvin <linux@horizon.com>
Signed-off-by: Zheng Liu <wenqing.lz@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>

diff --git a/debugfs/dump.c b/debugfs/dump.c
index a15a0b7..9409ab6 100644 (file)
--- a/debugfs/dump.c
+++ b/debugfs/dump.c
@@ -105,10 +105,10 @@ static void dump_file(const char *cmdname, ext2_ino_t ino, int fd,
 {
        errcode_t retval;
        struct ext2_inode       inode;
-       char            buf[8192];
+       char            *buf = 0;
        ext2_file_t     e2_file;
        int             nbytes;
-       unsigned int    got;
+       unsigned int    got, blocksize = current_fs->blocksize;
 
        if (debugfs_read_inode(ino, &inode, cmdname))
                return;
@@ -118,8 +118,13 @@ static void dump_file(const char *cmdname, ext2_ino_t ino, int fd,
                com_err(cmdname, retval, "while opening ext2 file");
                return;
        }
+       retval = ext2fs_get_mem(blocksize, &buf);
+       if (retval) {
+               com_err(cmdname, retval, "while allocating memory");
+               return;
+       }
        while (1) {
-               retval = ext2fs_file_read(e2_file, buf, sizeof(buf), &got);
+               retval = ext2fs_file_read(e2_file, buf, blocksize, &got);
                if (retval)
                        com_err(cmdname, retval, "while reading ext2 file");
                if (got == 0)
@@ -128,6 +133,8 @@ static void dump_file(const char *cmdname, ext2_ino_t ino, int fd,
                if ((unsigned) nbytes != got)
                        com_err(cmdname, errno, "while writing file");
        }
+       if (buf)
+               ext2fs_free_mem(&buf);
        retval = ext2fs_file_close(e2_file);
        if (retval) {
                com_err(cmdname, retval, "while closing ext2 file");