Re: [PATCH 08/23] md: simplify md_setup_drive

From: NeilBrown
Date: Wed Jul 15 2020 - 19:37:51 EST


On Tue, Jul 14 2020, Christoph Hellwig wrote:

> Move the loop over the possible arrays into the caller to remove a level
> of indentation for the whole function.
>
> Signed-off-by: Christoph Hellwig <hch@xxxxxx>
> Acked-by: Song Liu <song@xxxxxxxxxx>

Nice

Reviewed-by: NeilBrown <neilb@xxxxxxx>

Thanks,
NeilBrown

> ---
> drivers/md/md-autodetect.c | 203 ++++++++++++++++++-------------------
> 1 file changed, 101 insertions(+), 102 deletions(-)
>
> diff --git a/drivers/md/md-autodetect.c b/drivers/md/md-autodetect.c
> index 6bc9b734eee6ff..a43a8f1580584c 100644
> --- a/drivers/md/md-autodetect.c
> +++ b/drivers/md/md-autodetect.c
> @@ -27,7 +27,7 @@ static int __initdata raid_noautodetect=1;
> #endif
> static int __initdata raid_autopart;
>
> -static struct {
> +static struct md_setup_args {
> int minor;
> int partitioned;
> int level;
> @@ -126,122 +126,117 @@ static inline int create_dev(char *name, dev_t dev)
> return ksys_mknod(name, S_IFBLK|0600, new_encode_dev(dev));
> }
>
> -static void __init md_setup_drive(void)
> +static void __init md_setup_drive(struct md_setup_args *args)
> {
> - int minor, i, ent, partitioned;
> + 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 name[16];
>
> - for (ent = 0; ent < md_setup_ents ; ent++) {
> - int fd;
> - int err = 0;
> - char *devname;
> - mdu_disk_info_t dinfo;
> - char name[16];
> + minor = args->minor;
> + partitioned = args->partitioned;
> + devname = args->device_names;
>
> - minor = md_setup_args[ent].minor;
> - partitioned = md_setup_args[ent].partitioned;
> - devname = md_setup_args[ent].device_names;
> + 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];
>
> - 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];
> + p = strchr(devname, ',');
> + if (p)
> + *p++ = 0;
>
> - p = strchr(devname, ',');
> - if (p)
> - *p++ = 0;
> + dev = name_to_dev_t(devname);
> + if (strncmp(devname, "/dev/", 5) == 0)
> + devname += 5;
> + snprintf(comp_name, 63, "/dev/%s", devname);
> + 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);
> + break;
> + }
>
> - dev = name_to_dev_t(devname);
> - if (strncmp(devname, "/dev/", 5) == 0)
> - devname += 5;
> - snprintf(comp_name, 63, "/dev/%s", devname);
> - 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);
> - break;
> - }
> + devices[i] = dev;
> + devname = p;
> + }
> + devices[i] = 0;
>
> - devices[i] = dev;
> + if (!i)
> + return;
>
> - devname = p;
> - }
> - devices[i] = 0;
> + printk(KERN_INFO "md: Loading md%s%d: %s\n",
> + partitioned ? "_d" : "", minor,
> + args->device_names);
>
> - if (!i)
> - continue;
> + fd = ksys_open(name, 0, 0);
> + if (fd < 0) {
> + printk(KERN_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;
> + }
>
> - printk(KERN_INFO "md: Loading md%s%d: %s\n",
> - partitioned ? "_d" : "", minor,
> - md_setup_args[ent].device_names);
> + 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.not_persistent = 1;
>
> - fd = ksys_open(name, 0, 0);
> - if (fd < 0) {
> - printk(KERN_ERR "md: open failed - cannot start "
> - "array %s\n", name);
> - continue;
> - }
> - 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);
> - continue;
> + 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;
> + 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);
> }
> -
> - if (md_setup_args[ent].level != LEVEL_NONE) {
> - /* non-persistent */
> - mdu_array_info_t ainfo;
> - ainfo.level = md_setup_args[ent].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.not_persistent = 1;
> -
> - ainfo.state = (1 << MD_SB_CLEAN);
> - ainfo.layout = 0;
> - ainfo.chunk_size = md_setup_args[ent].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;
> - 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);
> - }
> + } 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);
> }
> - if (!err)
> - err = ksys_ioctl(fd, RUN_ARRAY, 0);
> - if (err)
> - printk(KERN_WARNING "md: starting md%d failed\n", minor);
> - ksys_close(fd);
> }
> + if (!err)
> + err = ksys_ioctl(fd, RUN_ARRAY, 0);
> + if (err)
> + printk(KERN_WARNING "md: starting md%d failed\n", minor);
> + ksys_close(fd);
> }
>
> static int __init raid_setup(char *str)
> @@ -289,11 +284,15 @@ static void __init autodetect_raid(void)
>
> 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
> autodetect_raid();
> - md_setup_drive();
> +
> + for (ent = 0; ent < md_setup_ents; ent++)
> + md_setup_drive(&md_setup_args[ent]);
> }
> --
> 2.27.0

Attachment: signature.asc
Description: PGP signature