Commit 7e0adbfc authored by Christoph Hellwig's avatar Christoph Hellwig
Browse files

md: rewrite md_setup_drive to avoid ioctls 



md_setup_drive knows it works with md devices, so it is rather pointless
to open a file descriptor and issue ioctls.  Just call directly into the
relevant low-level md routines after getting a handle to the device using
blkdev_get_by_dev instead.

Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Reviewed-by: default avatarNeilBrown <neilb@suse.de>
Acked-by: default avatarSong Liu <song@kernel.org>
Acked-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent d1100488

drivers/md/md-autodetect.c

+63 −71
Original line number Diff line number Diff line
@@ -2,7 +2,6 @@ 
#include <linux/kernel.h>

#include <linux/blkdev.h>

#include <linux/init.h>

#include <linux/syscalls.h>

#include <linux/mount.h>

#include <linux/major.h>

#include <linux/delay.h>
@@ -120,37 +119,29 @@ static int __init md_setup(char *str) 
	return 1;

}



static inline int create_dev(char *name, dev_t dev)

{

	ksys_unlink(name);

	return ksys_mknod(name, S_IFBLK|0600, new_encode_dev(dev));

}



static void __init md_setup_drive(struct md_setup_args *args)

{

	int minor, i, partitioned;

	dev_t dev;

	dev_t devices[MD_SB_DISKS+1];

	int fd;

	int err = 0;

	char *devname;

	mdu_disk_info_t dinfo;

	char *devname = args->device_names;

	dev_t devices[MD_SB_DISKS + 1], mdev;

	struct mdu_array_info_s ainfo = { };

	struct block_device *bdev;

	struct mddev *mddev;

	int err = 0, i;

	char name[16];



	minor = args->minor;

	partitioned = args->partitioned;

	devname = args->device_names;

	if (args->partitioned) {

		mdev = MKDEV(mdp_major, args->minor << MdpMinorShift);

		sprintf(name, "md_d%d", args->minor);

	} else {

		mdev = MKDEV(MD_MAJOR, args->minor);

		sprintf(name, "md%d", args->minor);

	}



	sprintf(name, "/dev/md%s%d", partitioned?"_d":"", minor);

	if (partitioned)

		dev = MKDEV(mdp_major, minor << MdpMinorShift);

	else

		dev = MKDEV(MD_MAJOR, minor);

	create_dev(name, dev);

	for (i = 0; i < MD_SB_DISKS && devname != NULL; i++) {

		struct kstat stat;

		char *p;

		char comp_name[64];

		dev_t dev;



		p = strchr(devname, ',');

		if (p)
@@ -163,7 +154,7 @@ static void __init md_setup_drive(struct md_setup_args *args) 
		if (vfs_stat(comp_name, &stat) == 0 && S_ISBLK(stat.mode))

			dev = new_decode_dev(stat.rdev);

		if (!dev) {

			printk(KERN_WARNING "md: Unknown device name: %s\n", devname);

			pr_warn("md: Unknown device name: %s\n", devname);

			break;

		}
@@ -175,68 +166,71 @@ static void __init md_setup_drive(struct md_setup_args *args) 
	if (!i)

		return;



	printk(KERN_INFO "md: Loading md%s%d: %s\n",

		partitioned ? "_d" : "", minor,

		args->device_names);

	pr_info("md: Loading %s: %s\n", name, args->device_names);



	fd = ksys_open(name, 0, 0);

	if (fd < 0) {

		printk(KERN_ERR "md: open failed - cannot start "

				"array %s\n", name);

	bdev = blkdev_get_by_dev(mdev, FMODE_READ, NULL);

	if (IS_ERR(bdev)) {

		pr_err("md: open failed - cannot start array %s\n", name);

		return;

	}

	if (ksys_ioctl(fd, SET_ARRAY_INFO, 0) == -EBUSY) {

		printk(KERN_WARNING

		       "md: Ignoring md=%d, already autodetected. (Use raid=noautodetect)\n",

		       minor);

		ksys_close(fd);

		return;



	err = -EIO;

	if (WARN(bdev->bd_disk->fops != &md_fops,

			"Opening block device %x resulted in non-md device\n",

			mdev))

		goto out_blkdev_put;



	mddev = bdev->bd_disk->private_data;



	err = mddev_lock(mddev);

	if (err) {

		pr_err("md: failed to lock array %s\n", name);

		goto out_blkdev_put;

	}



	if (!list_empty(&mddev->disks) || mddev->raid_disks) {

		pr_warn("md: Ignoring %s, already autodetected. (Use raid=noautodetect)\n",

		       name);

		goto out_unlock;

	}



	if (args->level != LEVEL_NONE) {

		/* non-persistent */

		mdu_array_info_t ainfo;

		ainfo.level = args->level;

		ainfo.size = 0;

		ainfo.nr_disks =0;

		ainfo.raid_disks =0;

		while (devices[ainfo.raid_disks])

			ainfo.raid_disks++;

		ainfo.md_minor =minor;

		ainfo.md_minor = args->minor;

		ainfo.not_persistent = 1;



		ainfo.state = (1 << MD_SB_CLEAN);

		ainfo.layout = 0;

		ainfo.chunk_size = args->chunk;

		err = ksys_ioctl(fd, SET_ARRAY_INFO, (long)&ainfo);

		for (i = 0; !err && i <= MD_SB_DISKS; i++) {

			dev = devices[i];

			if (!dev)

				break;

		while (devices[ainfo.raid_disks])

			ainfo.raid_disks++;

	}



	err = md_set_array_info(mddev, &ainfo);



	for (i = 0; i <= MD_SB_DISKS && devices[i]; i++) {

		struct mdu_disk_info_s dinfo = {

			.major	= MAJOR(devices[i]),

			.minor	= MINOR(devices[i]),

		};



		if (args->level != LEVEL_NONE) {

			dinfo.number = i;

			dinfo.raid_disk = i;

			dinfo.state = (1<<MD_DISK_ACTIVE)|(1<<MD_DISK_SYNC);

			dinfo.major = MAJOR(dev);

			dinfo.minor = MINOR(dev);

			err = ksys_ioctl(fd, ADD_NEW_DISK,

					 (long)&dinfo);

		}

	} else {

		/* persistent */

		for (i = 0; i <= MD_SB_DISKS; i++) {

			dev = devices[i];

			if (!dev)

				break;

			dinfo.major = MAJOR(dev);

			dinfo.minor = MINOR(dev);

			ksys_ioctl(fd, ADD_NEW_DISK, (long)&dinfo);

			dinfo.state =

				(1 << MD_DISK_ACTIVE) | (1 << MD_DISK_SYNC);

		}



		md_add_new_disk(mddev, &dinfo);

	}



	if (!err)

		err = ksys_ioctl(fd, RUN_ARRAY, 0);

		err = do_md_run(mddev);

	if (err)

		printk(KERN_WARNING "md: starting md%d failed\n", minor);

	ksys_close(fd);

		pr_warn("md: starting %s failed\n", name);

out_unlock:

	mddev_unlock(mddev);

out_blkdev_put:

	blkdev_put(bdev, FMODE_READ);

}



static int __init raid_setup(char *str)
@@ -286,8 +280,6 @@ void __init md_run_setup(void) 
{

	int ent;



	create_dev("/dev/md0", MKDEV(MD_MAJOR, 0));



	if (raid_noautodetect)

		printk(KERN_INFO "md: Skipping autodetection of RAID arrays. (raid=autodetect will force)\n");

	else

drivers/md/md.c

+10 −14
Original line number Diff line number Diff line
@@ -326,8 +326,6 @@ static struct ctl_table raid_root_table[] = { 
	{  }

};



static const struct block_device_operations md_fops;



static int start_readonly;



/*
@@ -4368,7 +4366,6 @@ array_state_show(struct mddev *mddev, char *page) 


static int do_md_stop(struct mddev *mddev, int ro, struct block_device *bdev);

static int md_set_readonly(struct mddev *mddev, struct block_device *bdev);

static int do_md_run(struct mddev *mddev);

static int restart_array(struct mddev *mddev);



static ssize_t
@@ -6015,7 +6012,7 @@ abort: 
}

EXPORT_SYMBOL_GPL(md_run);



static int do_md_run(struct mddev *mddev)

int do_md_run(struct mddev *mddev)

{

	int err;
@@ -6651,7 +6648,7 @@ static int get_disk_info(struct mddev *mddev, void __user * arg) 
	return 0;

}



static int add_new_disk(struct mddev *mddev, mdu_disk_info_t *info)

int md_add_new_disk(struct mddev *mddev, struct mdu_disk_info_s *info)

{

	char b[BDEVNAME_SIZE], b2[BDEVNAME_SIZE];

	struct md_rdev *rdev;
@@ -6697,7 +6694,7 @@ static int add_new_disk(struct mddev *mddev, mdu_disk_info_t *info) 
	}



	/*

	 * add_new_disk can be used once the array is assembled

	 * md_add_new_disk can be used once the array is assembled

	 * to add "hot spares".  They must already have a superblock

	 * written

	 */
@@ -6810,7 +6807,7 @@ static int add_new_disk(struct mddev *mddev, mdu_disk_info_t *info) 
		return err;

	}



	/* otherwise, add_new_disk is only allowed

	/* otherwise, md_add_new_disk is only allowed

	 * for major_version==0 superblocks

	 */

	if (mddev->major_version != 0) {
@@ -7055,7 +7052,7 @@ static int set_bitmap_file(struct mddev *mddev, int fd) 
}



/*

 * set_array_info is used two different ways

 * md_set_array_info is used two different ways

 * The original usage is when creating a new array.

 * In this usage, raid_disks is > 0 and it together with

 *  level, size, not_persistent,layout,chunksize determine the
@@ -7067,9 +7064,8 @@ static int set_bitmap_file(struct mddev *mddev, int fd) 
 *  The minor and patch _version numbers are also kept incase the

 *  super_block handler wishes to interpret them.

 */

static int set_array_info(struct mddev *mddev, mdu_array_info_t *info)

int md_set_array_info(struct mddev *mddev, struct mdu_array_info_s *info)

{



	if (info->raid_disks == 0) {

		/* just setting version number for superblock loading */

		if (info->major_version < 0 ||
@@ -7560,7 +7556,7 @@ static int md_ioctl(struct block_device *bdev, fmode_t mode, 
			err = -EBUSY;

			goto unlock;

		}

		err = set_array_info(mddev, &info);

		err = md_set_array_info(mddev, &info);

		if (err) {

			pr_warn("md: couldn't set array info. %d\n", err);

			goto unlock;
@@ -7614,7 +7610,7 @@ static int md_ioctl(struct block_device *bdev, fmode_t mode, 
				/* Need to clear read-only for this */

				break;

			else

				err = add_new_disk(mddev, &info);

				err = md_add_new_disk(mddev, &info);

			goto unlock;

		}

		break;
@@ -7682,7 +7678,7 @@ static int md_ioctl(struct block_device *bdev, fmode_t mode, 
		if (copy_from_user(&info, argp, sizeof(info)))

			err = -EFAULT;

		else

			err = add_new_disk(mddev, &info);

			err = md_add_new_disk(mddev, &info);

		goto unlock;

	}
@@ -7808,7 +7804,7 @@ static int md_revalidate(struct gendisk *disk) 
	mddev->changed = 0;

	return 0;

}

static const struct block_device_operations md_fops =

const struct block_device_operations md_fops =

{

	.owner		= THIS_MODULE,

	.open		= md_open,

drivers/md/md.h

+8 −0
Original line number Diff line number Diff line
@@ -801,7 +801,15 @@ static inline void mddev_check_write_zeroes(struct mddev *mddev, struct bio *bio 
		mddev->queue->limits.max_write_zeroes_sectors = 0;

}



struct mdu_array_info_s;

struct mdu_disk_info_s;



extern int mdp_major;

void md_autostart_arrays(int part);

int md_set_array_info(struct mddev *mddev, struct mdu_array_info_s *info);

int md_add_new_disk(struct mddev *mddev, struct mdu_disk_info_s *info);

int do_md_run(struct mddev *mddev);



extern const struct block_device_operations md_fops;



#endif /* _MD_MD_H */

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