Commit cae0a771 authored by Artem Bityutskiy's avatar Artem Bityutskiy
Browse files

UBI: tweak volumes locking 



Transform vtbl_mutex to volumes_mutex - this just makes code
easier to understand.

Signed-off-by: default avatarArtem Bityutskiy <Artem.Bityutskiy@nokia.com>
parent 89b96b69

drivers/mtd/ubi/build.c

+1 −1
Original line number Diff line number Diff line
@@ -264,7 +264,7 @@ static int uif_init(struct ubi_device *ubi) 
	int i, err;

	dev_t dev;



	mutex_init(&ubi->vtbl_mutex);

	mutex_init(&ubi->volumes_mutex);

	spin_lock_init(&ubi->volumes_lock);



	sprintf(ubi->ubi_name, UBI_NAME_STR "%d", ubi->ubi_num);

drivers/mtd/ubi/kapi.c

+6 −5
Original line number Diff line number Diff line
@@ -162,15 +162,16 @@ struct ubi_volume_desc *ubi_open_volume(int ubi_num, int vol_id, int mode) 
	desc->mode = mode;



	/*

	 * To prevent simultaneous checks of the same volume we use @vtbl_mutex,

	 * although it is not the purpose it was introduced for.

	 * To prevent simultaneous checks of the same volume we use

	 * @volumes_mutex, although it is not the purpose it was introduced

	 * for.

	 */

	mutex_lock(&ubi->vtbl_mutex);

	mutex_lock(&ubi->volumes_mutex);

	if (!vol->checked) {

		/* This is the first open - check the volume */

		err = ubi_check_volume(ubi, vol_id);

		if (err < 0) {

			mutex_unlock(&ubi->vtbl_mutex);

			mutex_unlock(&ubi->volumes_mutex);

			ubi_close_volume(desc);

			return ERR_PTR(err);

		}
@@ -181,7 +182,7 @@ struct ubi_volume_desc *ubi_open_volume(int ubi_num, int vol_id, int mode) 
		}

		vol->checked = 1;

	}

	mutex_unlock(&ubi->vtbl_mutex);

	mutex_unlock(&ubi->volumes_mutex);

	return desc;



out_unlock:

drivers/mtd/ubi/ubi.h

+3 −2
Original line number Diff line number Diff line
@@ -255,7 +255,8 @@ struct ubi_wl_entry; 
 * @vtbl_slots: how many slots are available in the volume table

 * @vtbl_size: size of the volume table in bytes

 * @vtbl: in-RAM volume table copy

 * @vtbl_mutex: protects on-flash volume table

 * @volumes_mutex: protects on-flash volume table and serializes volume

 *                 changes, like creation, deletion, update, resize

 *

 * @max_ec: current highest erase counter value

 * @mean_ec: current mean erase counter value
@@ -333,7 +334,7 @@ struct ubi_device { 
	int vtbl_slots;

	int vtbl_size;

	struct ubi_vtbl_record *vtbl;

	struct mutex vtbl_mutex;

	struct mutex volumes_mutex;



	int max_ec;

	int mean_ec;

drivers/mtd/ubi/upd.c

+4 −0
Original line number Diff line number Diff line
@@ -67,7 +67,9 @@ static int set_update_marker(struct ubi_device *ubi, int vol_id) 
	memcpy(&vtbl_rec, &ubi->vtbl[vol_id], sizeof(struct ubi_vtbl_record));

	vtbl_rec.upd_marker = 1;



	mutex_lock(&ubi->volumes_mutex);

	err = ubi_change_vtbl_record(ubi, vol_id, &vtbl_rec);

	mutex_unlock(&ubi->volumes_mutex);

	vol->upd_marker = 1;

	return err;

}
@@ -106,7 +108,9 @@ static int clear_update_marker(struct ubi_device *ubi, int vol_id, long long byt 
			vol->last_eb_bytes = vol->usable_leb_size;

	}



	mutex_lock(&ubi->volumes_mutex);

	err = ubi_change_vtbl_record(ubi, vol_id, &vtbl_rec);

	mutex_unlock(&ubi->volumes_mutex);

	vol->upd_marker = 0;

	return err;

}

drivers/mtd/ubi/vmt.c

+16 −6
Original line number Diff line number Diff line
@@ -201,8 +201,8 @@ int ubi_create_volume(struct ubi_device *ubi, struct ubi_mkvol_req *req) 
	if (!vol)

		return -ENOMEM;



	mutex_lock(&ubi->volumes_mutex);

	spin_lock(&ubi->volumes_lock);



	if (vol_id == UBI_VOL_NUM_AUTO) {

		/* Find unused volume ID */

		dbg_msg("search for vacant volume ID");
@@ -350,6 +350,7 @@ int ubi_create_volume(struct ubi_device *ubi, struct ubi_mkvol_req *req) 
	spin_unlock(&ubi->volumes_lock);



	paranoid_check_volumes(ubi);

	mutex_unlock(&ubi->volumes_mutex);

	return 0;



out_gluebi:
@@ -365,6 +366,7 @@ int ubi_create_volume(struct ubi_device *ubi, struct ubi_mkvol_req *req) 
	ubi->volumes[vol_id] = NULL;

out_unlock:

	spin_unlock(&ubi->volumes_lock);

	mutex_unlock(&ubi->volumes_mutex);

	kfree(vol);

	ubi_err("cannot create volume %d, error %d", vol_id, err);

	return err;
@@ -382,6 +384,7 @@ int ubi_create_volume(struct ubi_device *ubi, struct ubi_mkvol_req *req) 
	ubi->avail_pebs += vol->reserved_pebs;

	ubi->volumes[vol_id] = NULL;

	spin_unlock(&ubi->volumes_lock);

	mutex_unlock(&ubi->volumes_mutex);

	volume_sysfs_close(vol);

	ubi_err("cannot create volume %d, error %d", vol_id, err);

	return err;
@@ -408,18 +411,19 @@ int ubi_remove_volume(struct ubi_volume_desc *desc) 
	if (ubi->ro_mode)

		return -EROFS;



	mutex_lock(&ubi->volumes_mutex);

	err = ubi_destroy_gluebi(vol);

	if (err)

		return err;

		goto out;



	err = ubi_change_vtbl_record(ubi, vol_id, NULL);

	if (err)

		return err;

		goto out;



	for (i = 0; i < vol->reserved_pebs; i++) {

		err = ubi_eba_unmap_leb(ubi, vol, i);

		if (err)

			return err;

			goto out;

	}



	spin_lock(&ubi->volumes_lock);
@@ -449,8 +453,13 @@ int ubi_remove_volume(struct ubi_volume_desc *desc) 
	spin_unlock(&ubi->volumes_lock);



	paranoid_check_volumes(ubi);

	mutex_unlock(&ubi->volumes_mutex);

	module_put(THIS_MODULE);

	return 0;



out:

	mutex_unlock(&ubi->volumes_mutex);

	return err;

}



/**
@@ -496,6 +505,7 @@ int ubi_resize_volume(struct ubi_volume_desc *desc, int reserved_pebs) 
		new_mapping[i] = UBI_LEB_UNMAPPED;



	/* Reserve physical eraseblocks */

	mutex_lock(&ubi->volumes_mutex);

	pebs = reserved_pebs - vol->reserved_pebs;

	if (pebs > 0) {

		spin_lock(&ubi->volumes_lock);
@@ -556,6 +566,7 @@ int ubi_resize_volume(struct ubi_volume_desc *desc, int reserved_pebs) 
	}



	paranoid_check_volumes(ubi);

	mutex_unlock(&ubi->volumes_mutex);

	return 0;



out_acc:
@@ -567,6 +578,7 @@ int ubi_resize_volume(struct ubi_volume_desc *desc, int reserved_pebs) 
	}

out_free:

	kfree(new_mapping);

	mutex_unlock(&ubi->volumes_mutex);

	return err;

}
@@ -829,9 +841,7 @@ static void paranoid_check_volumes(struct ubi_device *ubi) 
{

	int i;



	mutex_lock(&ubi->vtbl_mutex);

	for (i = 0; i < ubi->vtbl_slots; i++)

		paranoid_check_volume(ubi, i);

	mutex_unlock(&ubi->vtbl_mutex);

}

#endif