Commit bef17329 authored by Christoph Hellwig's avatar Christoph Hellwig
Browse files

initrd: switch initrd loading to struct file based APIs 



There is no good reason to mess with file descriptors from in-kernel
code, switch the initrd loading to struct file based read and writes
instead.

Also Pass an explicit offset instead of ->f_pos, and to make that easier,
use file scope file structs and offsets everywhere except for
identify_ramdisk_image instead of the current strange mix.

Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Acked-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 899ac10c

fs/read_write.c

+1 −1
Original line number Diff line number Diff line
@@ -301,7 +301,7 @@ loff_t vfs_llseek(struct file *file, loff_t offset, int whence) 
}

EXPORT_SYMBOL(vfs_llseek);



off_t ksys_lseek(unsigned int fd, off_t offset, unsigned int whence)

static off_t ksys_lseek(unsigned int fd, off_t offset, unsigned int whence)

{

	off_t retval;

	struct fd f = fdget_pos(fd);

include/linux/syscalls.h

+0 −1
Original line number Diff line number Diff line
@@ -1246,7 +1246,6 @@ int ksys_fchown(unsigned int fd, uid_t user, gid_t group); 
int ksys_getdents64(unsigned int fd, struct linux_dirent64 __user *dirent,

		    unsigned int count);

int ksys_ioctl(unsigned int fd, unsigned int cmd, unsigned long arg);

off_t ksys_lseek(unsigned int fd, off_t offset, unsigned int whence);

ssize_t ksys_read(unsigned int fd, char __user *buf, size_t count);

void ksys_sync(void);

int ksys_unshare(unsigned long unshare_flags);

init/do_mounts_rd.c

+39 −40
Original line number Diff line number Diff line
@@ -14,6 +14,8 @@ 


#include <linux/decompress/generic.h>



static struct file *in_file, *out_file;

static loff_t in_pos, out_pos;



static int __init prompt_ramdisk(char *str)

{
@@ -31,7 +33,7 @@ static int __init ramdisk_start_setup(char *str) 
}

__setup("ramdisk_start=", ramdisk_start_setup);



static int __init crd_load(int in_fd, int out_fd, decompress_fn deco);

static int __init crd_load(decompress_fn deco);



/*

 * This routine tries to find a RAM disk image to load, and returns the
@@ -53,7 +55,8 @@ static int __init crd_load(int in_fd, int out_fd, decompress_fn deco); 
 *	lz4

 */

static int __init

identify_ramdisk_image(int fd, int start_block, decompress_fn *decompressor)

identify_ramdisk_image(struct file *file, loff_t pos,

		decompress_fn *decompressor)

{

	const int size = 512;

	struct minix_super_block *minixsb;
@@ -64,6 +67,7 @@ identify_ramdisk_image(int fd, int start_block, decompress_fn *decompressor) 
	unsigned char *buf;

	const char *compress_name;

	unsigned long n;

	int start_block = rd_image_start;



	buf = kmalloc(size, GFP_KERNEL);

	if (!buf)
@@ -78,8 +82,8 @@ identify_ramdisk_image(int fd, int start_block, decompress_fn *decompressor) 
	/*

	 * Read block 0 to test for compressed kernel

	 */

	ksys_lseek(fd, start_block * BLOCK_SIZE, 0);

	ksys_read(fd, buf, size);

	pos = start_block * BLOCK_SIZE;

	kernel_read(file, buf, size, &pos);



	*decompressor = decompress_method(buf, size, &compress_name);

	if (compress_name) {
@@ -124,8 +128,8 @@ identify_ramdisk_image(int fd, int start_block, decompress_fn *decompressor) 
	/*

	 * Read 512 bytes further to check if cramfs is padded

	 */

	ksys_lseek(fd, start_block * BLOCK_SIZE + 0x200, 0);

	ksys_read(fd, buf, size);

	pos = start_block * BLOCK_SIZE + 0x200;

	kernel_read(file, buf, size, &pos);



	if (cramfsb->magic == CRAMFS_MAGIC) {

		printk(KERN_NOTICE
@@ -138,8 +142,8 @@ identify_ramdisk_image(int fd, int start_block, decompress_fn *decompressor) 
	/*

	 * Read block 1 to test for minix and ext2 superblock

	 */

	ksys_lseek(fd, (start_block+1) * BLOCK_SIZE, 0);

	ksys_read(fd, buf, size);

	pos = (start_block + 1) * BLOCK_SIZE;

	kernel_read(file, buf, size, &pos);



	/* Try minix */

	if (minixsb->s_magic == MINIX_SUPER_MAGIC ||
@@ -166,15 +170,22 @@ identify_ramdisk_image(int fd, int start_block, decompress_fn *decompressor) 
	       start_block);



done:

	ksys_lseek(fd, start_block * BLOCK_SIZE, 0);

	kfree(buf);

	return nblocks;

}



static unsigned long nr_blocks(struct file *file)

{

	struct inode *inode = file->f_mapping->host;



	if (!S_ISBLK(inode->i_mode))

		return 0;

	return i_size_read(inode) >> 10;

}



int __init rd_load_image(char *from)

{

	int res = 0;

	int in_fd, out_fd;

	unsigned long rd_blocks, devblocks;

	int nblocks, i;

	char *buf = NULL;
@@ -184,20 +195,21 @@ int __init rd_load_image(char *from) 
	char rotator[4] = { '|' , '/' , '-' , '\\' };

#endif



	out_fd = ksys_open("/dev/ram", O_RDWR, 0);

	if (out_fd < 0)

	out_file = filp_open("/dev/ram", O_RDWR, 0);

	if (IS_ERR(out_file))

		goto out;



	in_fd = ksys_open(from, O_RDONLY, 0);

	if (in_fd < 0)

	in_file = filp_open(from, O_RDONLY, 0);

	if (IS_ERR(in_file))

		goto noclose_input;



	nblocks = identify_ramdisk_image(in_fd, rd_image_start, &decompressor);

	in_pos = rd_image_start * BLOCK_SIZE;

	nblocks = identify_ramdisk_image(in_file, in_pos, &decompressor);

	if (nblocks < 0)

		goto done;



	if (nblocks == 0) {

		if (crd_load(in_fd, out_fd, decompressor) == 0)

		if (crd_load(decompressor) == 0)

			goto successful_load;

		goto done;

	}
@@ -206,11 +218,7 @@ int __init rd_load_image(char *from) 
	 * NOTE NOTE: nblocks is not actually blocks but

	 * the number of kibibytes of data to load into a ramdisk.

	 */

	if (ksys_ioctl(out_fd, BLKGETSIZE, (unsigned long)&rd_blocks) < 0)

		rd_blocks = 0;

	else

		rd_blocks >>= 1;



	rd_blocks = nr_blocks(out_file);

	if (nblocks > rd_blocks) {

		printk("RAMDISK: image too big! (%dKiB/%ldKiB)\n",

		       nblocks, rd_blocks);
@@ -220,13 +228,10 @@ int __init rd_load_image(char *from) 
	/*

	 * OK, time to copy in the data

	 */

	if (ksys_ioctl(in_fd, BLKGETSIZE, (unsigned long)&devblocks) < 0)

		devblocks = 0;

	else

		devblocks >>= 1;



	if (strcmp(from, "/initrd.image") == 0)

		devblocks = nblocks;

	else

		devblocks = nr_blocks(in_file);



	if (devblocks == 0) {

		printk(KERN_ERR "RAMDISK: could not determine device size\n");
@@ -245,14 +250,11 @@ int __init rd_load_image(char *from) 
		if (i && (i % devblocks == 0)) {

			pr_cont("done disk #1.\n");

			rotate = 0;

			if (ksys_close(in_fd)) {

				printk("Error closing the disk.\n");

				goto noclose_input;

			}

			fput(in_file);

			break;

		}

		ksys_read(in_fd, buf, BLOCK_SIZE);

		ksys_write(out_fd, buf, BLOCK_SIZE);

		kernel_read(in_file, buf, BLOCK_SIZE, &in_pos);

		kernel_write(out_file, buf, BLOCK_SIZE, &out_pos);

#if !defined(CONFIG_S390)

		if (!(i % 16)) {

			pr_cont("%c\b", rotator[rotate & 0x3]);
@@ -265,9 +267,9 @@ int __init rd_load_image(char *from) 
successful_load:

	res = 1;

done:

	ksys_close(in_fd);

	fput(in_file);

noclose_input:

	ksys_close(out_fd);

	fput(out_file);

out:

	kfree(buf);

	ksys_unlink("/dev/ram");
@@ -283,11 +285,10 @@ int __init rd_load_disk(int n) 


static int exit_code;

static int decompress_error;

static int crd_infd, crd_outfd;



static long __init compr_fill(void *buf, unsigned long len)

{

	long r = ksys_read(crd_infd, buf, len);

	long r = kernel_read(in_file, buf, len, &in_pos);

	if (r < 0)

		printk(KERN_ERR "RAMDISK: error while reading compressed data");

	else if (r == 0)
@@ -297,7 +298,7 @@ static long __init compr_fill(void *buf, unsigned long len) 


static long __init compr_flush(void *window, unsigned long outcnt)

{

	long written = ksys_write(crd_outfd, window, outcnt);

	long written = kernel_write(out_file, window, outcnt, &out_pos);

	if (written != outcnt) {

		if (decompress_error == 0)

			printk(KERN_ERR
@@ -316,11 +317,9 @@ static void __init error(char *x) 
	decompress_error = 1;

}



static int __init crd_load(int in_fd, int out_fd, decompress_fn deco)

static int __init crd_load(decompress_fn deco)

{

	int result;

	crd_infd = in_fd;

	crd_outfd = out_fd;



	if (!deco) {

		pr_emerg("Invalid ramdisk decompression routine.  "

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