initramfs: switch initramfs unpacking to struct file based APIs (bf6419e4) · Commits · 戴 / test

init/initramfs.c

+26 −21

Original line number	Diff line number	Diff line
		@@ -13,13 +13,14 @@
		#include <linux/memblock.h>
		#include <linux/namei.h>

		static ssize_t __init xwrite(int fd, const char *p, size_t count)
		static ssize_t __init xwrite(struct file file, const char p, size_t count,
		loff_t *pos)
		{
		ssize_t out = 0;

		/* sys_write only can write MAX_RW_COUNT aka 2G-4K bytes at most */
		while (count) {
		ssize_t rv = ksys_write(fd, p, count);
		ssize_t rv = kernel_write(file, p, count, pos);

		if (rv < 0) {
		if (rv == -EINTR \|\| rv == -EAGAIN)
		@@ -317,7 +318,8 @@ static int __init maybe_link(void)
		return 0;
		}

		static __initdata int wfd;
		static __initdata struct file *wfile;
		static __initdata loff_t wfile_pos;

		static int __init do_name(void)
		{
		@@ -334,17 +336,18 @@ static int __init do_name(void)
		int openflags = O_WRONLY\|O_CREAT;
		if (ml != 1)
		openflags \|= O_TRUNC;
		wfd = ksys_open(collected, openflags, mode);
		wfile = filp_open(collected, openflags, mode);
		if (IS_ERR(wfile))
		return 0;
		wfile_pos = 0;

		if (wfd >= 0) {
		ksys_fchown(wfd, uid, gid);
		ksys_fchmod(wfd, mode);
		vfs_fchown(wfile, uid, gid);
		vfs_fchmod(wfile, mode);
		if (body_len)
		ksys_ftruncate(wfd, body_len);
		vfs_truncate(&wfile->f_path, body_len);
		vcollected = kstrdup(collected, GFP_KERNEL);
		state = CopyFile;
		}
		}
		} else if (S_ISDIR(mode)) {
		ksys_mkdir(collected, mode);
		ksys_chown(collected, uid, gid);
		@@ -365,16 +368,16 @@ static int __init do_name(void)
		static int __init do_copy(void)
		{
		if (byte_count >= body_len) {
		if (xwrite(wfd, victim, body_len) != body_len)
		if (xwrite(wfile, victim, body_len, &wfile_pos) != body_len)
		error("write error");
		ksys_close(wfd);
		fput(wfile);
		do_utime(vcollected, mtime);
		kfree(vcollected);
		eat(body_len);
		state = SkipIt;
		return 0;
		} else {
		if (xwrite(wfd, victim, byte_count) != byte_count)
		if (xwrite(wfile, victim, byte_count, &wfile_pos) != byte_count)
		error("write error");
		body_len -= byte_count;
		eat(byte_count);
		@@ -576,21 +579,23 @@ static inline bool kexec_free_initrd(void)
		static void __init populate_initrd_image(char *err)
		{
		ssize_t written;
		int fd;
		struct file *file;
		loff_t pos = 0;

		unpack_to_rootfs(__initramfs_start, __initramfs_size);

		printk(KERN_INFO "rootfs image is not initramfs (%s); looks like an initrd\n",
		err);
		fd = ksys_open("/initrd.image", O_WRONLY \| O_CREAT, 0700);
		if (fd < 0)
		file = filp_open("/initrd.image", O_WRONLY \| O_CREAT, 0700);
		if (IS_ERR(file))
		return;

		written = xwrite(fd, (char *)initrd_start, initrd_end - initrd_start);
		written = xwrite(file, (char *)initrd_start, initrd_end - initrd_start,
		&pos);
		if (written != initrd_end - initrd_start)
		pr_err("/initrd.image: incomplete write (%zd != %ld)\n",
		written, initrd_end - initrd_start);
		ksys_close(fd);
		fput(file);
		}
		#endif /* CONFIG_BLK_DEV_RAM */

Admin message