From f40ac9cdf6991287f19bdafe9b0752ee40137908 Mon Sep 17 00:00:00 2001 From: Artem Bityutskiy Date: Sun, 13 Jul 2008 21:47:47 +0300 Subject: [PATCH] UBI: implement multiple volumes rename Quite useful ioctl which allows to make atomic system upgrades. The idea belongs to Richard Titmuss Signed-off-by: Artem Bityutskiy --- drivers/mtd/ubi/build.c | 1 + drivers/mtd/ubi/cdev.c | 188 +++++++++++++++++++++++++++++++++++++++- drivers/mtd/ubi/ubi.h | 33 ++++++- drivers/mtd/ubi/vmt.c | 57 ++++++++++-- drivers/mtd/ubi/vtbl.c | 51 +++++++++++ include/mtd/ubi-user.h | 60 ++++++++++++- 6 files changed, 375 insertions(+), 15 deletions(-) diff --git a/drivers/mtd/ubi/build.c b/drivers/mtd/ubi/build.c index 7210e1da1fcb..4418a2369b56 100644 --- a/drivers/mtd/ubi/build.c +++ b/drivers/mtd/ubi/build.c @@ -806,6 +806,7 @@ int ubi_attach_mtd_dev(struct mtd_info *mtd, int ubi_num, int vid_hdr_offset) mutex_init(&ubi->buf_mutex); mutex_init(&ubi->ckvol_mutex); + mutex_init(&ubi->mult_mutex); mutex_init(&ubi->volumes_mutex); spin_lock_init(&ubi->volumes_lock); diff --git a/drivers/mtd/ubi/cdev.c b/drivers/mtd/ubi/cdev.c index 7c19918cc914..bc8199c6a9f5 100644 --- a/drivers/mtd/ubi/cdev.c +++ b/drivers/mtd/ubi/cdev.c @@ -605,6 +605,166 @@ static int verify_rsvol_req(const struct ubi_device *ubi, return 0; } +/** + * rename_volumes - rename UBI volumes. + * @ubi: UBI device description object + * @req: volumes re-name request + * + * This is a helper function for the volume re-name IOCTL which validates the + * the request, opens the volume and calls corresponding volumes management + * function. Returns zero in case of success and a negative error code in case + * of failure. + */ +static int rename_volumes(struct ubi_device *ubi, + struct ubi_rnvol_req *req) +{ + int i, n, err; + struct list_head rename_list; + struct ubi_rename_entry *re, *re1; + + if (req->count < 0 || req->count > UBI_MAX_RNVOL) + return -EINVAL; + + if (req->count == 0) + return 0; + + /* Validate volume IDs and names in the request */ + for (i = 0; i < req->count; i++) { + if (req->ents[i].vol_id < 0 || + req->ents[i].vol_id >= ubi->vtbl_slots) + return -EINVAL; + if (req->ents[i].name_len < 0) + return -EINVAL; + if (req->ents[i].name_len > UBI_VOL_NAME_MAX) + return -ENAMETOOLONG; + req->ents[i].name[req->ents[i].name_len] = '\0'; + n = strlen(req->ents[i].name); + if (n != req->ents[i].name_len) + err = -EINVAL; + } + + /* Make sure volume IDs and names are unique */ + for (i = 0; i < req->count - 1; i++) { + for (n = i + 1; n < req->count; n++) { + if (req->ents[i].vol_id == req->ents[n].vol_id) { + dbg_err("duplicated volume id %d", + req->ents[i].vol_id); + return -EINVAL; + } + if (!strcmp(req->ents[i].name, req->ents[n].name)) { + dbg_err("duplicated volume name \"%s\"", + req->ents[i].name); + return -EINVAL; + } + } + } + + /* Create the re-name list */ + INIT_LIST_HEAD(&rename_list); + for (i = 0; i < req->count; i++) { + int vol_id = req->ents[i].vol_id; + int name_len = req->ents[i].name_len; + const char *name = req->ents[i].name; + + re = kzalloc(sizeof(struct ubi_rename_entry), GFP_KERNEL); + if (!re) { + err = -ENOMEM; + goto out_free; + } + + re->desc = ubi_open_volume(ubi->ubi_num, vol_id, UBI_EXCLUSIVE); + if (IS_ERR(re->desc)) { + err = PTR_ERR(re->desc); + dbg_err("cannot open volume %d, error %d", vol_id, err); + kfree(re); + goto out_free; + } + + /* Skip this re-naming if the name does not really change */ + if (re->desc->vol->name_len == name_len && + !memcmp(re->desc->vol->name, name, name_len)) { + ubi_close_volume(re->desc); + kfree(re); + continue; + } + + re->new_name_len = name_len; + memcpy(re->new_name, name, name_len); + list_add_tail(&re->list, &rename_list); + dbg_msg("will rename volume %d from \"%s\" to \"%s\"", + vol_id, re->desc->vol->name, name); + } + + if (list_empty(&rename_list)) + return 0; + + /* Find out the volumes which have to be removed */ + list_for_each_entry(re, &rename_list, list) { + struct ubi_volume_desc *desc; + int no_remove_needed = 0; + + /* + * Volume @re->vol_id is going to be re-named to + * @re->new_name, while its current name is @name. If a volume + * with name @re->new_name currently exists, it has to be + * removed, unless it is also re-named in the request (@req). + */ + list_for_each_entry(re1, &rename_list, list) { + if (re->new_name_len == re1->desc->vol->name_len && + !memcmp(re->new_name, re1->desc->vol->name, + re1->desc->vol->name_len)) { + no_remove_needed = 1; + break; + } + } + + if (no_remove_needed) + continue; + + /* + * It seems we need to remove volume with name @re->new_name, + * if it exists. + */ + desc = ubi_open_volume_nm(ubi->ubi_num, re->new_name, UBI_EXCLUSIVE); + if (IS_ERR(desc)) { + err = PTR_ERR(desc); + if (err == -ENODEV) + /* Re-naming into a non-existing volume name */ + continue; + + /* The volume exists but busy, or an error occurred */ + dbg_err("cannot open volume \"%s\", error %d", + re->new_name, err); + goto out_free; + } + + re = kzalloc(sizeof(struct ubi_rename_entry), GFP_KERNEL); + if (!re) { + err = -ENOMEM; + ubi_close_volume(desc); + goto out_free; + } + + re->remove = 1; + re->desc = desc; + list_add(&re->list, &rename_list); + dbg_msg("will remove volume %d, name \"%s\"", + re->desc->vol->vol_id, re->desc->vol->name); + } + + mutex_lock(&ubi->volumes_mutex); + err = ubi_rename_volumes(ubi, &rename_list); + mutex_unlock(&ubi->volumes_mutex); + +out_free: + list_for_each_entry_safe(re, re1, &rename_list, list) { + ubi_close_volume(re->desc); + list_del(&re->list); + kfree(re); + } + return err; +} + static int ubi_cdev_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg) { @@ -670,7 +830,7 @@ static int ubi_cdev_ioctl(struct inode *inode, struct file *file, } mutex_lock(&ubi->volumes_mutex); - err = ubi_remove_volume(desc); + err = ubi_remove_volume(desc, 0); mutex_unlock(&ubi->volumes_mutex); /* @@ -717,6 +877,32 @@ static int ubi_cdev_ioctl(struct inode *inode, struct file *file, break; } + /* Re-name volumes command */ + case UBI_IOCRNVOL: + { + struct ubi_rnvol_req *req; + + dbg_msg("re-name volumes"); + req = kmalloc(sizeof(struct ubi_rnvol_req), GFP_KERNEL); + if (!req) { + err = -ENOMEM; + break; + }; + + err = copy_from_user(req, argp, sizeof(struct ubi_rnvol_req)); + if (err) { + err = -EFAULT; + kfree(req); + break; + } + + mutex_lock(&ubi->mult_mutex); + err = rename_volumes(ubi, req); + mutex_unlock(&ubi->mult_mutex); + kfree(req); + break; + } + default: err = -ENOTTY; break; diff --git a/drivers/mtd/ubi/ubi.h b/drivers/mtd/ubi/ubi.h index 1fc32c863b78..274c67916b34 100644 --- a/drivers/mtd/ubi/ubi.h +++ b/drivers/mtd/ubi/ubi.h @@ -131,6 +131,27 @@ struct ubi_ltree_entry { struct rw_semaphore mutex; }; +/** + * struct ubi_rename_entry - volume re-name description data structure. + * @new_name_len: new volume name length + * @new_name: new volume name + * @remove: if not zero, this volume should be removed, not re-named + * @desc: descriptor of the volume + * @list: links re-name entries into a list + * + * This data structure is utilized in the multiple volume re-name code. Namely, + * UBI first creates a list of &struct ubi_rename_entry objects from the + * &struct ubi_rnvol_req request object, and then utilizes this list to do all + * the job. + */ +struct ubi_rename_entry { + int new_name_len; + char new_name[UBI_VOL_NAME_MAX + 1]; + int remove; + struct ubi_volume_desc *desc; + struct list_head list; +}; + struct ubi_volume_desc; /** @@ -206,7 +227,7 @@ struct ubi_volume { int alignment; int data_pad; int name_len; - char name[UBI_VOL_NAME_MAX+1]; + char name[UBI_VOL_NAME_MAX + 1]; int upd_ebs; int ch_lnum; @@ -272,7 +293,7 @@ struct ubi_wl_entry; * @vtbl_size: size of the volume table in bytes * @vtbl: in-RAM volume table copy * @volumes_mutex: protects on-flash volume table and serializes volume - * changes, like creation, deletion, update, resize + * changes, like creation, deletion, update, re-size and re-name * * @max_ec: current highest erase counter value * @mean_ec: current mean erase counter value @@ -330,6 +351,8 @@ struct ubi_wl_entry; * @peb_buf1: a buffer of PEB size used for different purposes * @peb_buf2: another buffer of PEB size used for different purposes * @buf_mutex: proptects @peb_buf1 and @peb_buf2 + * @ckvol_mutex: serializes static volume checking when opening + * @mult_mutex: serializes operations on multiple volumes, like re-nameing * @dbg_peb_buf: buffer of PEB size used for debugging * @dbg_buf_mutex: proptects @dbg_peb_buf */ @@ -410,6 +433,7 @@ struct ubi_device { void *peb_buf2; struct mutex buf_mutex; struct mutex ckvol_mutex; + struct mutex mult_mutex; #ifdef CONFIG_MTD_UBI_DEBUG void *dbg_peb_buf; struct mutex dbg_buf_mutex; @@ -426,12 +450,15 @@ extern struct mutex ubi_devices_mutex; /* vtbl.c */ int ubi_change_vtbl_record(struct ubi_device *ubi, int idx, struct ubi_vtbl_record *vtbl_rec); +int ubi_vtbl_rename_volumes(struct ubi_device *ubi, + struct list_head *rename_list); int ubi_read_volume_table(struct ubi_device *ubi, struct ubi_scan_info *si); /* vmt.c */ int ubi_create_volume(struct ubi_device *ubi, struct ubi_mkvol_req *req); -int ubi_remove_volume(struct ubi_volume_desc *desc); +int ubi_remove_volume(struct ubi_volume_desc *desc, int no_vtbl); int ubi_resize_volume(struct ubi_volume_desc *desc, int reserved_pebs); +int ubi_rename_volumes(struct ubi_device *ubi, struct list_head *rename_list); int ubi_add_volume(struct ubi_device *ubi, struct ubi_volume *vol); void ubi_free_volume(struct ubi_device *ubi, struct ubi_volume *vol); diff --git a/drivers/mtd/ubi/vmt.c b/drivers/mtd/ubi/vmt.c index 2cd886a5adac..4be4014c70df 100644 --- a/drivers/mtd/ubi/vmt.c +++ b/drivers/mtd/ubi/vmt.c @@ -402,13 +402,14 @@ int ubi_create_volume(struct ubi_device *ubi, struct ubi_mkvol_req *req) /** * ubi_remove_volume - remove volume. * @desc: volume descriptor + * @no_vtbl: do not change volume table if not zero * * This function removes volume described by @desc. The volume has to be opened * in "exclusive" mode. Returns zero in case of success and a negative error * code in case of failure. The caller has to have the @ubi->volumes_mutex * locked. */ -int ubi_remove_volume(struct ubi_volume_desc *desc) +int ubi_remove_volume(struct ubi_volume_desc *desc, int no_vtbl) { struct ubi_volume *vol = desc->vol; struct ubi_device *ubi = vol->ubi; @@ -437,9 +438,11 @@ int ubi_remove_volume(struct ubi_volume_desc *desc) if (err) goto out_err; - err = ubi_change_vtbl_record(ubi, vol_id, NULL); - if (err) - goto out_err; + if (!no_vtbl) { + err = ubi_change_vtbl_record(ubi, vol_id, NULL); + if (err) + goto out_err; + } for (i = 0; i < vol->reserved_pebs; i++) { err = ubi_eba_unmap_leb(ubi, vol, i); @@ -465,7 +468,8 @@ int ubi_remove_volume(struct ubi_volume_desc *desc) ubi->vol_count -= 1; spin_unlock(&ubi->volumes_lock); - err = paranoid_check_volumes(ubi); + if (!no_vtbl) + err = paranoid_check_volumes(ubi); return err; out_err: @@ -601,6 +605,44 @@ int ubi_resize_volume(struct ubi_volume_desc *desc, int reserved_pebs) return err; } +/** + * ubi_rename_volumes - re-name UBI volumes. + * @ubi: UBI device description object + * @renam_list: list of &struct ubi_rename_entry objects + * + * This function re-names or removes volumes specified in the re-name list. + * Returns zero in case of success and a negative error code in case of + * failure. + */ +int ubi_rename_volumes(struct ubi_device *ubi, struct list_head *rename_list) +{ + int err; + struct ubi_rename_entry *re; + + err = ubi_vtbl_rename_volumes(ubi, rename_list); + if (err) + return err; + + list_for_each_entry(re, rename_list, list) { + if (re->remove) { + err = ubi_remove_volume(re->desc, 1); + if (err) + break; + } else { + struct ubi_volume *vol = re->desc->vol; + + spin_lock(&ubi->volumes_lock); + vol->name_len = re->new_name_len; + memcpy(vol->name, re->new_name, re->new_name_len + 1); + spin_unlock(&ubi->volumes_lock); + } + } + + if (!err) + paranoid_check_volumes(ubi); + return err; +} + /** * ubi_add_volume - add volume. * @ubi: UBI device description object @@ -826,10 +868,9 @@ static int paranoid_check_volume(struct ubi_device *ubi, int vol_id) fail: ubi_err("paranoid check failed for volume %d", vol_id); - if (vol) { + if (vol) ubi_dbg_dump_vol_info(vol); - ubi_dbg_dump_vtbl_record(&ubi->vtbl[vol_id], vol_id); - } + ubi_dbg_dump_vtbl_record(&ubi->vtbl[vol_id], vol_id); spin_unlock(&ubi->volumes_lock); return -EINVAL; } diff --git a/drivers/mtd/ubi/vtbl.c b/drivers/mtd/ubi/vtbl.c index 05fb72fd268f..23c5376234b2 100644 --- a/drivers/mtd/ubi/vtbl.c +++ b/drivers/mtd/ubi/vtbl.c @@ -114,6 +114,57 @@ int ubi_change_vtbl_record(struct ubi_device *ubi, int idx, return 0; } +/** + * ubi_vtbl_rename_volumes - rename UBI volumes in the volume table. + * @ubi: UBI device description object + * @renam_list: list of &struct ubi_rename_entry objects + * + * This function re-names multiple volumes specified in @req in the volume + * table. Returns zero in case of success and a negative error code in case of + * failure. + */ +int ubi_vtbl_rename_volumes(struct ubi_device *ubi, + struct list_head *rename_list) +{ + int i, err; + struct ubi_rename_entry *re; + struct ubi_volume *layout_vol; + + list_for_each_entry(re, rename_list, list) { + uint32_t crc; + struct ubi_volume *vol = re->desc->vol; + struct ubi_vtbl_record *vtbl_rec = &ubi->vtbl[vol->vol_id]; + + if (re->remove) { + memcpy(vtbl_rec, &empty_vtbl_record, + sizeof(struct ubi_vtbl_record)); + continue; + } + + vtbl_rec->name_len = cpu_to_be16(re->new_name_len); + memcpy(vtbl_rec->name, re->new_name, re->new_name_len); + memset(vtbl_rec->name + re->new_name_len, 0, + UBI_VOL_NAME_MAX + 1 - re->new_name_len); + crc = crc32(UBI_CRC32_INIT, vtbl_rec, + UBI_VTBL_RECORD_SIZE_CRC); + vtbl_rec->crc = cpu_to_be32(crc); + } + + layout_vol = ubi->volumes[vol_id2idx(ubi, UBI_LAYOUT_VOLUME_ID)]; + for (i = 0; i < UBI_LAYOUT_VOLUME_EBS; i++) { + err = ubi_eba_unmap_leb(ubi, layout_vol, i); + if (err) + return err; + + err = ubi_eba_write_leb(ubi, layout_vol, i, ubi->vtbl, 0, + ubi->vtbl_size, UBI_LONGTERM); + if (err) + return err; + } + + return 0; +} + /** * vtbl_check - check if volume table is not corrupted and contains sensible * data. diff --git a/include/mtd/ubi-user.h b/include/mtd/ubi-user.h index a7421f130cc0..e8e57c3dfcdb 100644 --- a/include/mtd/ubi-user.h +++ b/include/mtd/ubi-user.h @@ -58,6 +58,13 @@ * device should be used. A &struct ubi_rsvol_req object has to be properly * filled and a pointer to it has to be passed to the IOCTL. * + * UBI volumes re-name + * ~~~~~~~~~~~~~~~~~~~ + * + * To re-name several volumes atomically at one go, the %UBI_IOCRNVOL command + * of the UBI character device should be used. A &struct ubi_rnvol_req object + * has to be properly filled and a pointer to it has to be passed to the IOCTL. + * * UBI volume update * ~~~~~~~~~~~~~~~~~ * @@ -104,6 +111,8 @@ #define UBI_IOCRMVOL _IOW(UBI_IOC_MAGIC, 1, int32_t) /* Re-size an UBI volume */ #define UBI_IOCRSVOL _IOW(UBI_IOC_MAGIC, 2, struct ubi_rsvol_req) +/* Re-name volumes */ +#define UBI_IOCRNVOL _IOW(UBI_IOC_MAGIC, 3, struct ubi_rnvol_req) /* IOCTL commands of the UBI control character device */ @@ -128,6 +137,9 @@ /* Maximum MTD device name length supported by UBI */ #define MAX_UBI_MTD_NAME_LEN 127 +/* Maximum amount of UBI volumes that can be re-named at one go */ +#define UBI_MAX_RNVOL 32 + /* * UBI data type hint constants. * @@ -189,7 +201,7 @@ struct ubi_attach_req { int32_t ubi_num; int32_t mtd_num; int32_t vid_hdr_offset; - uint8_t padding[12]; + int8_t padding[12]; }; /** @@ -250,6 +262,48 @@ struct ubi_rsvol_req { int32_t vol_id; } __attribute__ ((packed)); +/** + * struct ubi_rnvol_req - volumes re-name request. + * @count: count of volumes to re-name + * @padding1: reserved for future, not used, has to be zeroed + * @vol_id: ID of the volume to re-name + * @name_len: name length + * @padding2: reserved for future, not used, has to be zeroed + * @name: new volume name + * + * UBI allows to re-name up to %32 volumes at one go. The count of volumes to + * re-name is specified in the @count field. The ID of the volumes to re-name + * and the new names are specified in the @vol_id and @name fields. + * + * The UBI volume re-name operation is atomic, which means that should power cut + * happen, the volumes will have either old name or new name. So the possible + * use-cases of this command is atomic upgrade. Indeed, to upgrade, say, volumes + * A and B one may create temporary volumes %A1 and %B1 with the new contents, + * then atomically re-name A1->A and B1->B, in which case old %A and %B will + * be removed. + * + * If it is not desirable to remove old A and B, the re-name request has to + * contain 4 entries: A1->A, A->A1, B1->B, B->B1, in which case old A1 and B1 + * become A and B, and old A and B will become A1 and B1. + * + * It is also OK to request: A1->A, A1->X, B1->B, B->Y, in which case old A1 + * and B1 become A and B, and old A and B become X and Y. + * + * In other words, in case of re-naming into an existing volume name, the + * existing volume is removed, unless it is re-named as well at the same + * re-name request. + */ +struct ubi_rnvol_req { + int32_t count; + int8_t padding1[12]; + struct { + int32_t vol_id; + int16_t name_len; + int8_t padding2[2]; + char name[UBI_MAX_VOLUME_NAME + 1]; + } ents[UBI_MAX_RNVOL]; +} __attribute__ ((packed)); + /** * struct ubi_leb_change_req - a data structure used in atomic logical * eraseblock change requests. @@ -261,8 +315,8 @@ struct ubi_rsvol_req { struct ubi_leb_change_req { int32_t lnum; int32_t bytes; - uint8_t dtype; - uint8_t padding[7]; + int8_t dtype; + int8_t padding[7]; } __attribute__ ((packed)); #endif /* __UBI_USER_H__ */