From 2973c74afaa532f3f72639b463322b2523519c20 Mon Sep 17 00:00:00 2001 From: Robert Yang Date: Mon, 23 Dec 2013 03:28:12 -0500 Subject: [PATCH 05/11] misc/create_inode.c: copy regular file The do_write_internal() is used for copying file from native fs to target, most of the code are from debugfs/debugfs.c, the debugfs/debugfs.c will be modified to use this function. Upstream-Status: Backport Signed-off-by: Robert Yang Reviewed-by: Darren Hart --- misc/create_inode.c | 183 +++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 183 insertions(+) diff --git a/misc/create_inode.c b/misc/create_inode.c index f845103..98f4a93 100644 --- a/misc/create_inode.c +++ b/misc/create_inode.c @@ -8,6 +8,16 @@ # endif #endif +/* 64KiB is the minimium blksize to best minimize system call overhead. */ +#ifndef IO_BUFSIZE +#define IO_BUFSIZE 64*1024 +#endif + +/* Block size for `st_blocks' */ +#ifndef S_BLKSIZE +#define S_BLKSIZE 512 +#endif + /* Make a special file which is block, character and fifo */ errcode_t do_mknod_internal(ext2_ino_t cwd, const char *name, struct stat *st) { @@ -127,9 +137,182 @@ errcode_t do_mkdir_internal(ext2_ino_t cwd, const char *name, struct stat *st) { } +static errcode_t copy_file(int fd, ext2_ino_t newfile, int bufsize, int make_holes) +{ + ext2_file_t e2_file; + errcode_t retval; + int got; + unsigned int written; + char *buf; + char *ptr; + char *zero_buf; + int cmp; + + retval = ext2fs_file_open(current_fs, newfile, + EXT2_FILE_WRITE, &e2_file); + if (retval) + return retval; + + retval = ext2fs_get_mem(bufsize, &buf); + if (retval) { + com_err("copy_file", retval, "can't allocate buffer\n"); + return retval; + } + + /* This is used for checking whether the whole block is zero */ + retval = ext2fs_get_memzero(bufsize, &zero_buf); + if (retval) { + com_err("copy_file", retval, "can't allocate buffer\n"); + ext2fs_free_mem(&buf); + return retval; + } + + while (1) { + got = read(fd, buf, bufsize); + if (got == 0) + break; + if (got < 0) { + retval = errno; + goto fail; + } + ptr = buf; + + /* Sparse copy */ + if (make_holes) { + /* Check whether all is zero */ + cmp = memcmp(ptr, zero_buf, got); + if (cmp == 0) { + /* The whole block is zero, make a hole */ + retval = ext2fs_file_lseek(e2_file, got, EXT2_SEEK_CUR, NULL); + if (retval) + goto fail; + got = 0; + } + } + + /* Normal copy */ + while (got > 0) { + retval = ext2fs_file_write(e2_file, ptr, + got, &written); + if (retval) + goto fail; + + got -= written; + ptr += written; + } + } + ext2fs_free_mem(&buf); + ext2fs_free_mem(&zero_buf); + retval = ext2fs_file_close(e2_file); + return retval; + +fail: + ext2fs_free_mem(&buf); + ext2fs_free_mem(&zero_buf); + (void) ext2fs_file_close(e2_file); + return retval; +} + /* Copy the native file to the fs */ errcode_t do_write_internal(ext2_ino_t cwd, const char *src, const char *dest) { + int fd; + struct stat statbuf; + ext2_ino_t newfile; + errcode_t retval; + struct ext2_inode inode; + int bufsize = IO_BUFSIZE; + int make_holes = 0; + + fd = open(src, O_RDONLY); + if (fd < 0) { + com_err(src, errno, 0); + return errno; + } + if (fstat(fd, &statbuf) < 0) { + com_err(src, errno, 0); + close(fd); + return errno; + } + + retval = ext2fs_namei(current_fs, root, cwd, dest, &newfile); + if (retval == 0) { + com_err(__func__, 0, "The file '%s' already exists\n", dest); + close(fd); + return retval; + } + + retval = ext2fs_new_inode(current_fs, cwd, 010755, 0, &newfile); + if (retval) { + com_err(__func__, retval, 0); + close(fd); + return retval; + } +#ifdef DEBUGFS + printf("Allocated inode: %u\n", newfile); +#endif + retval = ext2fs_link(current_fs, cwd, dest, newfile, + EXT2_FT_REG_FILE); + if (retval == EXT2_ET_DIR_NO_SPACE) { + retval = ext2fs_expand_dir(current_fs, cwd); + if (retval) { + com_err(__func__, retval, "while expanding directory"); + close(fd); + return retval; + } + retval = ext2fs_link(current_fs, cwd, dest, newfile, + EXT2_FT_REG_FILE); + } + if (retval) { + com_err(dest, retval, 0); + close(fd); + return retval; + } + if (ext2fs_test_inode_bitmap2(current_fs->inode_map, newfile)) + com_err(__func__, 0, "Warning: inode already set"); + ext2fs_inode_alloc_stats2(current_fs, newfile, +1, 0); + memset(&inode, 0, sizeof(inode)); + inode.i_mode = (statbuf.st_mode & ~LINUX_S_IFMT) | LINUX_S_IFREG; + inode.i_atime = inode.i_ctime = inode.i_mtime = + current_fs->now ? current_fs->now : time(0); + inode.i_links_count = 1; + inode.i_size = statbuf.st_size; + if (current_fs->super->s_feature_incompat & + EXT3_FEATURE_INCOMPAT_EXTENTS) { + int i; + struct ext3_extent_header *eh; + + eh = (struct ext3_extent_header *) &inode.i_block[0]; + eh->eh_depth = 0; + eh->eh_entries = 0; + eh->eh_magic = ext2fs_cpu_to_le16(EXT3_EXT_MAGIC); + i = (sizeof(inode.i_block) - sizeof(*eh)) / + sizeof(struct ext3_extent); + eh->eh_max = ext2fs_cpu_to_le16(i); + inode.i_flags |= EXT4_EXTENTS_FL; + } + + if ((retval = ext2fs_write_new_inode(current_fs, newfile, &inode))) { + com_err(__func__, retval, "while creating inode %u", newfile); + close(fd); + return retval; + } + if (LINUX_S_ISREG(inode.i_mode)) { + if (statbuf.st_blocks < statbuf.st_size / S_BLKSIZE) { + make_holes = 1; + /* + * Use I/O blocksize as buffer size when + * copying sparse files. + */ + bufsize = statbuf.st_blksize; + } + retval = copy_file(fd, newfile, bufsize, make_holes); + if (retval) + com_err("copy_file", retval, 0); + } + close(fd); + + return 0; } /* Copy files from source_dir to fs */ -- 1.7.10.4