As of now with out this patch the content under the dir /sys/fs/btrfs/<fsid>/devices is just links to the block devs.
Moving forward we would need the above btrfs sysfs path to contain more info about the btrfs devices. This patch provide a framework and as of now a fault notification interface, which is needed to notify when disk disappear. The idea is to call /sys/fs/btrfs/<fsid>/devices/<disk>/fault when we get a kobject notification about the disk disappearance. Signed-off-by: Anand Jain <[email protected]> --- fs/btrfs/sysfs.c | 110 +++++++++++++++++++++++++++++++++++++++++------------ fs/btrfs/sysfs.h | 3 ++ fs/btrfs/volumes.c | 5 +++ fs/btrfs/volumes.h | 2 + 4 files changed, 96 insertions(+), 24 deletions(-) diff --git a/fs/btrfs/sysfs.c b/fs/btrfs/sysfs.c index f729199..7c80a99 100644 --- a/fs/btrfs/sysfs.c +++ b/fs/btrfs/sysfs.c @@ -31,6 +31,7 @@ #include "transaction.h" #include "sysfs.h" #include "volumes.h" +#include "rcu-string.h" static inline struct btrfs_fs_info *to_fs_info(struct kobject *kobj); @@ -475,19 +476,6 @@ static void __btrfs_sysfs_remove_one(struct btrfs_fs_info *fs_info) wait_for_completion(&fs_info->kobj_unregister); } -void btrfs_sysfs_remove_one(struct btrfs_fs_info *fs_info) -{ - if (fs_info->space_info_kobj) { - sysfs_remove_files(fs_info->space_info_kobj, allocation_attrs); - kobject_del(fs_info->space_info_kobj); - kobject_put(fs_info->space_info_kobj); - } - kobject_del(fs_info->device_dir_kobj); - kobject_put(fs_info->device_dir_kobj); - addrm_unknown_feature_attrs(fs_info, false); - sysfs_remove_group(&fs_info->super_kobj, &btrfs_feature_attr_group); - __btrfs_sysfs_remove_one(fs_info); -} const char * const btrfs_feature_set_names[3] = { [FEAT_COMPAT] = "compat", @@ -564,36 +552,91 @@ static void init_feature_attrs(void) } } -static int add_device_membership(struct btrfs_fs_info *fs_info) + +#define to_btrfs_device(_kobj) container_of(_kobj, struct btrfs_device, device_kobj) + +static ssize_t device_kobj_fault_store(struct kobject *dev_kobj, + struct kobj_attribute *a, const char *buf, size_t len) +{ + struct btrfs_device *dev = to_btrfs_device(dev_kobj); + + if (dev->missing || !dev->bdev) + return -EINVAL; + + /* Fixme: Call appropriate device check status handler */ + + return len; +} + +BTRFS_ATTR_RW(fault, 0200, NULL, device_kobj_fault_store); + +static struct attribute *device_kobj_attrs[] = { + BTRFS_ATTR_PTR(fault), + NULL, +}; + +static void device_kobj_release(struct kobject *dev_kobj) +{ + /* nothing to free as of now */ +} + +struct kobj_type device_ktype = { + .sysfs_ops = &kobj_sysfs_ops, + .release = device_kobj_release, + .default_attrs = device_kobj_attrs, +}; + +int device_add_kobject(struct btrfs_fs_info *fs_info) { int error = 0; struct btrfs_fs_devices *fs_devices = fs_info->fs_devices; struct btrfs_device *dev; - fs_info->device_dir_kobj = kobject_create_and_add("devices", + if (!fs_info->device_dir_kobj) + fs_info->device_dir_kobj = kobject_create_and_add("devices", &fs_info->super_kobj); if (!fs_info->device_dir_kobj) return -ENOMEM; list_for_each_entry(dev, &fs_devices->devices, dev_list) { - struct hd_struct *disk; - struct kobject *disk_kobj; - if (!dev->bdev) + if (!dev->bdev || dev->missing || dev->device_kobj.parent) continue; - disk = dev->bdev->bd_part; - disk_kobj = &part_to_dev(disk)->kobj; + error = kobject_init_and_add(&dev->device_kobj, &device_ktype, + fs_info->device_dir_kobj, "%s", + strrchr(rcu_str_deref(dev->name), '/') + 1); - error = sysfs_create_link(fs_info->device_dir_kobj, - disk_kobj, disk_kobj->name); if (error) break; } - return error; } +/* + * Remove the sysfs entries for the devices. + * devid provides a perticular devid for which the sysfs entry + * has to be removed, if -1 it would remove for all devs + */ +void device_rm_kobject(struct btrfs_fs_info *fs_info, u64 devid) +{ + struct btrfs_fs_devices *fs_devices = fs_info->fs_devices; + struct btrfs_device *dev; + + if (!fs_info->device_dir_kobj) + return; + + list_for_each_entry(dev, &fs_devices->devices, dev_list) { + if (!dev->device_kobj.parent) + continue; + + if (devid == -1 || devid == dev->devid) { + kobject_del(&dev->device_kobj); + kobject_put(&dev->device_kobj); + } + } +} + /* /sys/fs/btrfs/ entry */ static struct kset *btrfs_kset; @@ -603,6 +646,25 @@ static struct dentry *btrfs_debugfs_root_dentry; /* Debugging tunables and exported data */ u64 btrfs_debugfs_test; +void btrfs_sysfs_remove_one(struct btrfs_fs_info *fs_info) +{ + if (fs_info->space_info_kobj) { + sysfs_remove_files(fs_info->space_info_kobj, allocation_attrs); + kobject_del(fs_info->space_info_kobj); + kobject_put(fs_info->space_info_kobj); + } + + if (fs_info->device_dir_kobj) { + device_rm_kobject(fs_info, -1); + kobject_del(fs_info->device_dir_kobj); + kobject_put(fs_info->device_dir_kobj); + } + + addrm_unknown_feature_attrs(fs_info, false); + sysfs_remove_group(&fs_info->super_kobj, &btrfs_feature_attr_group); + __btrfs_sysfs_remove_one(fs_info); +} + int btrfs_sysfs_add_one(struct btrfs_fs_info *fs_info) { int error; @@ -625,7 +687,7 @@ int btrfs_sysfs_add_one(struct btrfs_fs_info *fs_info) if (error) goto failure; - error = add_device_membership(fs_info); + error = device_add_kobject(fs_info); if (error) goto failure; diff --git a/fs/btrfs/sysfs.h b/fs/btrfs/sysfs.h index 9ab5763..ff4b87b 100644 --- a/fs/btrfs/sysfs.h +++ b/fs/btrfs/sysfs.h @@ -66,4 +66,7 @@ char *btrfs_printable_features(enum btrfs_feature_set set, u64 flags); extern const char * const btrfs_feature_set_names[3]; extern struct kobj_type space_info_ktype; extern struct kobj_type btrfs_raid_ktype; + +int device_add_kobject(struct btrfs_fs_info *fs_info); +void device_rm_kobject(struct btrfs_fs_info *fs_info, u64 devid); #endif /* _BTRFS_SYSFS_H_ */ diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c index db211fd..27dfbb4 100644 --- a/fs/btrfs/volumes.c +++ b/fs/btrfs/volumes.c @@ -40,6 +40,7 @@ #include "rcu-string.h" #include "math.h" #include "dev-replace.h" +#include "sysfs.h" static int init_first_rw_device(struct btrfs_trans_handle *trans, struct btrfs_root *root, @@ -1633,6 +1634,9 @@ int btrfs_rm_device(struct btrfs_root *root, char *device_path) cur_devices = device->fs_devices; mutex_lock(&root->fs_info->fs_devices->device_list_mutex); + + device_rm_kobject(root->fs_info, device->devid); + list_del_rcu(&device->dev_list); device->fs_devices->num_devices--; @@ -2129,6 +2133,7 @@ int btrfs_init_new_device(struct btrfs_root *root, char *device_path) btrfs_abort_transaction(trans, root, ret); goto error_trans; } + device_add_kobject(root->fs_info); } /* diff --git a/fs/btrfs/volumes.h b/fs/btrfs/volumes.h index 4ca67b3..a434611 100644 --- a/fs/btrfs/volumes.h +++ b/fs/btrfs/volumes.h @@ -113,6 +113,8 @@ struct btrfs_device { int dev_stats_valid; int dev_stats_dirty; /* counters need to be written to disk */ atomic_t dev_stat_values[BTRFS_DEV_STAT_VALUES_MAX]; + + struct kobject device_kobj; }; struct btrfs_fs_devices { -- 1.8.5.3 -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
