/* * Copyright (C) 2012 Red Hat, Inc. * * This file is part of LVM2. * * This copyrighted material is made available to anyone wishing to use, * modify, copy, or redistribute it subject to the terms and conditions * of the GNU Lesser General Public License v.2.1. * * You should have received a copy of the GNU Lesser General Public License * along with this program; if not, write to the Free Software Foundation, * Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ #ifndef _LVM_METAD_H #define _LVM_METAD_H #include "config-util.h" struct volume_group; struct cmd_context; struct dm_config_tree; enum activation_change; typedef int (*activation_handler) (struct cmd_context *cmd, const char *vgname, const char *vgid, int partial, int changed, enum activation_change activate); #ifdef LVMETAD_SUPPORT /* * Initialise the communication with lvmetad. Normally called by * lvmcache_init. Sets up a global handle for our process. */ void lvmetad_init(struct cmd_context *); /* * Override the use of lvmetad for retrieving scan results and metadata. */ void lvmetad_set_active(int); /* * Configure the socket that lvmetad_init will use to connect to the daemon. */ void lvmetad_set_socket(const char *); /* * Check whether lvmetad is used. */ int lvmetad_used(void); /* * Check if lvmetad socket is present (either the one set by lvmetad_set_socket * or the default one if not set). For example, this may be used before calling * lvmetad_active() check that does connect to the socket - this would produce * various connection errors if the socket is not present. */ int lvmetad_socket_present(void); /* * Check whether lvmetad is active (where active means both that it is running * and that we have a working connection with it). */ int lvmetad_active(void); /* * Connect to lvmetad unless the connection is already open or lvmetad is * not configured to be used. If we fail to connect, print a warning. */ void lvmetad_connect_or_warn(void); /* * Drop connection to lvmetad. A subsequent lvmetad_init() will re-establish * the connection (possibly at a different socket path). */ void lvmetad_disconnect(void); /* * Set the "lvmetad validity token" (currently only consists of the lvmetad * filter. See lvm.conf. */ void lvmetad_set_token(const struct dm_config_value *filter); /* * Release allocated token. */ void lvmetad_release_token(void); // FIXME What's described here doesn't appear to be implemented yet. /* * Send a new version of VG metadata to lvmetad. This is normally called after * vg_write but before vg_commit. After vg_commit, lvmetad_vg_commit is called * to seal the transaction. The result of lvmetad_vg_update is that the new * metadata is stored tentatively in lvmetad, but it is not used until * lvmetad_vg_commit. The request is validated immediately and lvmetad_vg_commit * only constitutes a pointer update. */ int lvmetad_vg_update(struct volume_group *vg); /* * Inform lvmetad that a VG has been removed. This is not entirely safe, but is * only needed during vgremove, which does not wipe PV labels and therefore * cannot mark the PVs as gone. */ int lvmetad_vg_remove(struct volume_group *vg); /* * Notify lvmetad that a PV has been found. It is not an error if the PV is * already marked as present in lvmetad. If a non-NULL vg pointer is supplied, * it is taken to represent the metadata read from the MDA(s) present on that * PV. It *is* an error if: the VG is already known to lvmetad, the sequence * number on the cached and on the discovered PV match but the metadata content * does not. */ int lvmetad_pv_found(const struct id *pvid, struct device *dev, const struct format_type *fmt, uint64_t label_sector, struct volume_group *vg, activation_handler handler); /* * Inform the daemon that the device no longer exists. */ int lvmetad_pv_gone(dev_t devno, const char *pv_name, activation_handler handler); int lvmetad_pv_gone_by_dev(struct device *dev, activation_handler handler); /* * Request a list of all PVs available to lvmetad. If requested, this will also * read labels off all the PVs to populate lvmcache. */ int lvmetad_pv_list_to_lvmcache(struct cmd_context *cmd); /* * Lookup an individual PV. * If found is not NULL, it is set according to whether or not the PV is found, * otherwise if the PV is not found an error is returned. */ int lvmetad_pv_lookup(struct cmd_context *cmd, struct id pvid, int *found); int lvmetad_pv_lookup_by_dev(struct cmd_context *cmd, struct device *dev, int *found); /* * Request a list of all VGs available to lvmetad and use it to fill in * lvmcache.. */ int lvmetad_vg_list_to_lvmcache(struct cmd_context *cmd); /* * Find a VG by its ID or its name in the lvmetad cache. Gives NULL if the VG is * not found. */ struct volume_group *lvmetad_vg_lookup(struct cmd_context *cmd, const char *vgname, const char *vgid); /* * Scan a single device and update lvmetad with the result(s). */ int lvmetad_pvscan_single(struct cmd_context *cmd, struct device *dev, activation_handler handler); int lvmetad_pvscan_all_devs(struct cmd_context *cmd, activation_handler handler); # else /* LVMETAD_SUPPORT */ # define lvmetad_init(cmd) do { } while (0) # define lvmetad_disconnect() do { } while (0) # define lvmetad_set_active(a) do { } while (0) # define lvmetad_set_socket(a) do { } while (0) # define lvmetad_used() (0) # define lvmetad_socket_present() (0) # define lvmetad_active() (0) # define lvmetad_connect_or_warn() do { } while (0) # define lvmetad_set_token(a) do { } while (0) # define lvmetad_release_token() do { } while (0) # define lvmetad_vg_update(vg) (1) # define lvmetad_vg_remove(vg) (1) # define lvmetad_pv_found(pvid, dev, fmt, label_sector, vg, handler) (1) # define lvmetad_pv_gone(devno, pv_name, handler) (1) # define lvmetad_pv_gone_by_dev(dev, handler) (1) # define lvmetad_pv_list_to_lvmcache(cmd) (1) # define lvmetad_pv_lookup(cmd, pvid, found) (0) # define lvmetad_pv_lookup_by_dev(cmd, dev, found) (0) # define lvmetad_vg_list_to_lvmcache(cmd) (1) # define lvmetad_vg_lookup(cmd, vgname, vgid) (NULL) # define lvmetad_pvscan_single(cmd, dev, handler) (0) # define lvmetad_pvscan_all_devs(cmd, handler) (0) # endif /* LVMETAD_SUPPORT */ #endif