diff options
| -rw-r--r-- | lib/cache/lvmcache.c | 115 | ||||
| -rw-r--r-- | lib/cache/lvmcache.h | 9 | ||||
| -rw-r--r-- | lib/format_text/format-text.c | 4 | ||||
| -rw-r--r-- | lib/label/label.c | 10 | ||||
| -rw-r--r-- | lib/locking/locking.c | 4 | ||||
| -rw-r--r-- | tools/toollib.c | 57 |
6 files changed, 170 insertions, 29 deletions
diff --git a/lib/cache/lvmcache.c b/lib/cache/lvmcache.c index 017134d7d..a015b9fef 100644 --- a/lib/cache/lvmcache.c +++ b/lib/cache/lvmcache.c @@ -88,6 +88,9 @@ static int _vgs_locked = 0; static int _found_duplicate_vgnames = 0; static int _outdated_warning = 0; +static const char *_scan_lock_global_file = DEFAULT_RUN_DIR "/scan_lock_global"; +static int _scan_lock_global_file_exists = 0; + int lvmcache_init(struct cmd_context *cmd) { /* @@ -2742,19 +2745,115 @@ bool lvmcache_scan_mismatch(struct cmd_context *cmd, const char *vgname, const c return true; } -static uint64_t _max_metadata_size; +/* + * max_size_bytes and max_size_percent may come from different areas and + * different vgs because of different area sizes. + */ +static uint64_t _max_metadata_size_bytes; +static dm_percent_t _max_metadata_size_percent = DM_PERCENT_INVALID; -void lvmcache_save_metadata_size(uint64_t val) +void lvmcache_save_metadata_size_bytes(uint64_t val) { - if (!_max_metadata_size) - _max_metadata_size = val; - else if (_max_metadata_size < val) - _max_metadata_size = val; + if (!_max_metadata_size_bytes) + _max_metadata_size_bytes = val; + else if (_max_metadata_size_bytes < val) + _max_metadata_size_bytes = val; +} + +uint64_t lvmcache_max_metadata_size_bytes(void) +{ + return _max_metadata_size_bytes; +} + +/* + * TODO: enable/disable scan_lock_global with config setting: + * y: always use it + * n: never use it + * auto (default): use based on /run/lvm/scan_lock_global + */ +void lvmcache_save_metadata_size_percent(uint64_t meta_size, uint64_t mdah_size) +{ + + dm_percent_t pc = dm_make_percent(meta_size, mdah_size); + + if (pc == DM_PERCENT_INVALID || pc == DM_PERCENT_FAILED || + pc == DM_PERCENT_0 || pc == DM_PERCENT_1) + return; + + if (_max_metadata_size_percent == DM_PERCENT_INVALID) { + _max_metadata_size_percent = pc; + return; + } + + if (_max_metadata_size_percent < pc) + _max_metadata_size_percent = pc; +} + +/* + * TODO: make the percent at which scan_lock_global is used + * configurable? + */ +#define SCAN_LOCK_GLOBAL_METADATA_PERCENT (DM_PERCENT_1 * 25) + +void set_scan_lock_global(struct cmd_context *cmd) +{ + FILE *fp; + + if (_max_metadata_size_percent == DM_PERCENT_INVALID) + return; + + if (_max_metadata_size_percent >= SCAN_LOCK_GLOBAL_METADATA_PERCENT) { + if (_scan_lock_global_file_exists) + return; + log_debug("Creating %s.", _scan_lock_global_file); + if (!(fp = fopen(_scan_lock_global_file, "w"))) + return; + if (fclose(fp)) + stack; + } else { + if (_scan_lock_global_file_exists) { + log_debug("Unlinking %s.", _scan_lock_global_file); + if (unlink(_scan_lock_global_file)) + stack; + } + } } -uint64_t lvmcache_max_metadata_size(void) +int do_scan_lock_global(struct cmd_context *cmd, int *gl_ex) { - return _max_metadata_size; + struct stat buf; + + if (cmd->nolocking) + return 0; + + /* global lock is already held */ + if (cmd->lockf_global_ex) + return 0; + + if (!stat(_scan_lock_global_file, &buf)) { + _scan_lock_global_file_exists = 1; + + /* + * Tell the caller to use sh or ex. A command that may write + * vg metadata should use ex, otherwise sh. + * + * lockd_vg_default_sh/LOCKD_VG_SH is set for commands that + * do not modify vg metadata. + * + * FIXME: this variable/flag was previously used only for + * lvmlockd locking logic, but is now more general, so + * it should be renamed. + */ + if (cmd->lockd_vg_default_sh) + *gl_ex = 0; + else + *gl_ex = 1; + + return 1; + + } + + return 0; } int lvmcache_vginfo_has_pvid(struct lvmcache_vginfo *vginfo, char *pvid) diff --git a/lib/cache/lvmcache.h b/lib/cache/lvmcache.h index 76429fc5b..ea9284af1 100644 --- a/lib/cache/lvmcache.h +++ b/lib/cache/lvmcache.h @@ -183,8 +183,9 @@ bool lvmcache_scan_mismatch(struct cmd_context *cmd, const char *vgname, const c int lvmcache_vginfo_has_pvid(struct lvmcache_vginfo *vginfo, char *pvid); -uint64_t lvmcache_max_metadata_size(void); -void lvmcache_save_metadata_size(uint64_t val); +uint64_t lvmcache_max_metadata_size_bytes(void); +void lvmcache_save_metadata_size_bytes(uint64_t val); +void lvmcache_save_metadata_size_percent(uint64_t meta_size, uint64_t mdah_size); int dev_in_device_list(struct device *dev, struct dm_list *head); @@ -226,4 +227,8 @@ void lvmcache_extra_md_component_checks(struct cmd_context *cmd); unsigned int lvmcache_vg_info_count(void); +void set_scan_lock_global(struct cmd_context *cmd); +int do_scan_lock_global(struct cmd_context *cmd, int *gl_ex); + + #endif diff --git a/lib/format_text/format-text.c b/lib/format_text/format-text.c index 64ad4677c..9c4aedce0 100644 --- a/lib/format_text/format-text.c +++ b/lib/format_text/format-text.c @@ -1646,7 +1646,9 @@ int read_metadata_location_summary(const struct format_type *fmt, vgsummary->mda_size = rlocn->size; /* Keep track of largest metadata size we find. */ - lvmcache_save_metadata_size(rlocn->size); + lvmcache_save_metadata_size_bytes(rlocn->size); + /* Keep track of the most full metadata area. */ + lvmcache_save_metadata_size_percent(rlocn->size, mdah->size); lvmcache_lookup_mda(vgsummary); diff --git a/lib/label/label.c b/lib/label/label.c index 7eef1d99a..3f2305e0e 100644 --- a/lib/label/label.c +++ b/lib/label/label.c @@ -1221,7 +1221,7 @@ int label_scan(struct cmd_context *cmd) * If the largest metadata is within 1MB of the bcache size, then start * warning. */ - max_metadata_size_bytes = lvmcache_max_metadata_size(); + max_metadata_size_bytes = lvmcache_max_metadata_size_bytes(); if (max_metadata_size_bytes + (1024 * 1024) > _current_bcache_size_bytes) { /* we want bcache to be 1MB larger than the max metadata seen */ @@ -1236,6 +1236,14 @@ int label_scan(struct cmd_context *cmd) (unsigned long long)want_size_kb); } + /* + * If vg metadata is using a large percentage of a metadata area, then + * create /run/lvm/scan_lock_global to tell future lvm commands to + * begin doing lock_global() prior to scanning to avoid problems due to + * metadata wrapping between label_scan and vg_read. + */ + set_scan_lock_global(cmd); + dm_list_init(&cmd->hints); /* diff --git a/lib/locking/locking.c b/lib/locking/locking.c index 0aceb194a..3236b523a 100644 --- a/lib/locking/locking.c +++ b/lib/locking/locking.c @@ -359,10 +359,8 @@ static int _lockf_global(struct cmd_context *cmd, const char *mode, int convert, if (!strcmp(mode, "ex")) { flags |= LCK_WRITE; - if (cmd->lockf_global_ex) { - log_warn("global flock already held ex"); + if (cmd->lockf_global_ex) return 1; - } ret = lock_vol(cmd, VG_GLOBAL, flags, NULL); if (ret) diff --git a/tools/toollib.c b/tools/toollib.c index 338551015..0d47eb29d 100644 --- a/tools/toollib.c +++ b/tools/toollib.c @@ -2140,6 +2140,7 @@ int process_each_vg(struct cmd_context *cmd, struct dm_list vgnameids_to_process; /* vgnameid_list */ int enable_all_vgs = (cmd->cname->flags & ALL_VGS_IS_DEFAULT); int process_all_vgs_on_system = 0; + int gl_ex = 0; int ret_max = ECMD_PROCESSED; int ret; @@ -2173,11 +2174,25 @@ int process_each_vg(struct cmd_context *cmd, process_all_vgs_on_system = 1; /* - * Needed for a current listing of the global VG namespace. + * The global lock will be taken prior to scanning if the + * /run/lvm/scan_lock_global file has been created by a prior command, + * indicating that vg metadata sizes are large enough to possibly wrap + * around the metadata area during label_scan or between label_scan and + * vg_read, which can invalidate the scan results (normally unlocked) + * and prevent a valid vg_read (which uses metadata locations saved by + * label_scan). */ - if (process_all_vgs_on_system && !lock_global(cmd, "sh")) { - ret_max = ECMD_FAILED; - goto_out; + if (do_scan_lock_global(cmd, &gl_ex)) { + if (!lock_global(cmd, gl_ex ? "ex" : "sh")) { + ret_max = ECMD_FAILED; + goto_out; + } + } else if (process_all_vgs_on_system) { + /* Needed for a current listing of the global VG namespace. */ + if (!lock_global(cmd, "sh")) { + ret_max = ECMD_FAILED; + goto_out; + } } /* @@ -3668,6 +3683,7 @@ int process_each_lv(struct cmd_context *cmd, struct dm_list vgnameids_to_process; /* vgnameid_list */ int enable_all_vgs = (cmd->cname->flags & ALL_VGS_IS_DEFAULT); int process_all_vgs_on_system = 0; + int gl_ex = 0; int ret_max = ECMD_PROCESSED; int ret; @@ -3722,12 +3738,17 @@ int process_each_lv(struct cmd_context *cmd, else if (dm_list_empty(&arg_vgnames) && handle->internal_report_for_select) process_all_vgs_on_system = 1; - /* - * Needed for a current listing of the global VG namespace. - */ - if (process_all_vgs_on_system && !lock_global(cmd, "sh")) { - ret_max = ECMD_FAILED; - goto_out; + if (do_scan_lock_global(cmd, &gl_ex)) { + if (!lock_global(cmd, gl_ex ? "ex" : "sh")) { + ret_max = ECMD_FAILED; + goto_out; + } + } else if (process_all_vgs_on_system) { + /* Needed for a current listing of the global VG namespace. */ + if (!lock_global(cmd, "sh")) { + ret_max = ECMD_FAILED; + goto_out; + } } /* @@ -4384,6 +4405,7 @@ int process_each_pv(struct cmd_context *cmd, struct device_id_list *dil; int process_all_pvs; int process_all_devices; + int gl_ex = 0; int ret_max = ECMD_PROCESSED; int ret; @@ -4434,10 +4456,17 @@ int process_each_pv(struct cmd_context *cmd, process_all_devices = process_all_pvs && (cmd->cname->flags & ENABLE_ALL_DEVS) && all_is_set; - /* Needed for a current listing of the global VG namespace. */ - if (!only_this_vgname && !lock_global(cmd, "sh")) { - ret_max = ECMD_FAILED; - goto_out; + if (do_scan_lock_global(cmd, &gl_ex)) { + if (!lock_global(cmd, gl_ex ? "ex" : "sh")) { + ret_max = ECMD_FAILED; + goto_out; + } + } else if (!only_this_vgname) { + /* Needed for a current listing of the global VG namespace. */ + if (!lock_global(cmd, "sh")) { + ret_max = ECMD_FAILED; + goto_out; + } } if (!(read_flags & PROCESS_SKIP_SCAN)) |