On Tue, Jul 14 2020, Christoph Hellwig wrote: > 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: Christoph Hellwig > Acked-by: Song Liu > --- > drivers/md/md-autodetect.c | 127 ++++++++++++++++--------------------- > drivers/md/md.c | 20 +++--- > drivers/md/md.h | 6 ++ > 3 files changed, 71 insertions(+), 82 deletions(-) > > diff --git a/drivers/md/md-autodetect.c b/drivers/md/md-autodetect.c > index a43a8f1580584c..5b24b5616d3acc 100644 > --- a/drivers/md/md-autodetect.c > +++ b/drivers/md/md-autodetect.c > @@ -2,7 +2,6 @@ > #include > #include > #include > -#include > #include > #include > #include > @@ -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 +166,64 @@ 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; I'd be more comfortable if you added something like if (WARN(bdev->bd_disk->fops != md_fops, "Opening block device %x resulted in non-md device\")) return; here. However even without that Reviewed-by: NeilBrown Thanks, NeilBrown > + 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< - 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 +273,6 @@ 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 > diff --git a/drivers/md/md.c b/drivers/md/md.c > index 6e9a48da474848..9960cfeb59a50c 100644 > --- a/drivers/md/md.c > +++ b/drivers/md/md.c > @@ -4368,7 +4368,6 @@ 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 +6014,7 @@ int md_run(struct mddev *mddev) > } > EXPORT_SYMBOL_GPL(md_run); > > -static int do_md_run(struct mddev *mddev) > +int do_md_run(struct mddev *mddev) > { > int err; > > @@ -6651,7 +6650,7 @@ 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 +6696,7 @@ 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 +6809,7 @@ 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 +7054,7 @@ 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 +7066,8 @@ 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 +7558,7 @@ 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 +7612,7 @@ 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 +7680,7 @@ 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; > } > > diff --git a/drivers/md/md.h b/drivers/md/md.h > index 6f8fff77ce10a5..7ee81aa2eac862 100644 > --- a/drivers/md/md.h > +++ b/drivers/md/md.h > @@ -801,7 +801,13 @@ 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); > > #endif /* _MD_MD_H */ > -- > 2.27.0