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* 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux: (230 commits) Revert "tracing: Include module.h in define_trace.h" irq: don't put module.h into irq.h for tracking irqgen modules. bluetooth: macroize two small inlines to avoid module.h ip_vs.h: fix implicit use of module_get/module_put from module.h nf_conntrack.h: fix up fallout from implicit moduleparam.h presence include: replace linux/module.h with "struct module" wherever possible include: convert various register fcns to macros to avoid include chaining crypto.h: remove unused crypto_tfm_alg_modname() inline uwb.h: fix implicit use of asm/page.h for PAGE_SIZE pm_runtime.h: explicitly requires notifier.h linux/dmaengine.h: fix implicit use of bitmap.h and asm/page.h miscdevice.h: fix up implicit use of lists and types stop_machine.h: fix implicit use of smp.h for smp_processor_id of: fix implicit use of errno.h in include/linux/of.h of_platform.h: delete needless include <linux/module.h> acpi: remove module.h include from platform/aclinux.h miscdevice.h: delete unnecessary inclusion of module.h device_cgroup.h: delete needless include <linux/module.h> net: sch_generic remove redundant use of <linux/module.h> net: inet_timewait_sock doesnt need <linux/module.h> ... Fix up trivial conflicts (other header files, and removal of the ab3550 mfd driver) in - drivers/media/dvb/frontends/dibx000_common.c - drivers/media/video/{mt9m111.c,ov6650.c} - drivers/mfd/ab3550-core.c - include/linux/dmaengine.h
818 lines
19 KiB
C
818 lines
19 KiB
C
/*
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* Copyright (C) 2006-2009 Red Hat, Inc.
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*
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* This file is released under the LGPL.
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*/
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#include <linux/bio.h>
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#include <linux/slab.h>
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#include <linux/dm-dirty-log.h>
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#include <linux/device-mapper.h>
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#include <linux/dm-log-userspace.h>
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#include <linux/module.h>
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#include "dm-log-userspace-transfer.h"
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#define DM_LOG_USERSPACE_VSN "1.1.0"
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struct flush_entry {
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int type;
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region_t region;
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struct list_head list;
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};
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/*
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* This limit on the number of mark and clear request is, to a degree,
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* arbitrary. However, there is some basis for the choice in the limits
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* imposed on the size of data payload by dm-log-userspace-transfer.c:
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* dm_consult_userspace().
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*/
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#define MAX_FLUSH_GROUP_COUNT 32
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struct log_c {
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struct dm_target *ti;
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struct dm_dev *log_dev;
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uint32_t region_size;
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region_t region_count;
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uint64_t luid;
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char uuid[DM_UUID_LEN];
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char *usr_argv_str;
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uint32_t usr_argc;
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/*
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* in_sync_hint gets set when doing is_remote_recovering. It
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* represents the first region that needs recovery. IOW, the
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* first zero bit of sync_bits. This can be useful for to limit
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* traffic for calls like is_remote_recovering and get_resync_work,
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* but be take care in its use for anything else.
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*/
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uint64_t in_sync_hint;
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/*
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* Mark and clear requests are held until a flush is issued
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* so that we can group, and thereby limit, the amount of
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* network traffic between kernel and userspace. The 'flush_lock'
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* is used to protect these lists.
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*/
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spinlock_t flush_lock;
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struct list_head mark_list;
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struct list_head clear_list;
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};
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static mempool_t *flush_entry_pool;
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static void *flush_entry_alloc(gfp_t gfp_mask, void *pool_data)
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{
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return kmalloc(sizeof(struct flush_entry), gfp_mask);
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}
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static void flush_entry_free(void *element, void *pool_data)
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{
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kfree(element);
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}
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static int userspace_do_request(struct log_c *lc, const char *uuid,
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int request_type, char *data, size_t data_size,
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char *rdata, size_t *rdata_size)
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{
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int r;
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/*
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* If the server isn't there, -ESRCH is returned,
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* and we must keep trying until the server is
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* restored.
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*/
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retry:
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r = dm_consult_userspace(uuid, lc->luid, request_type, data,
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data_size, rdata, rdata_size);
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if (r != -ESRCH)
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return r;
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DMERR(" Userspace log server not found.");
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while (1) {
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set_current_state(TASK_INTERRUPTIBLE);
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schedule_timeout(2*HZ);
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DMWARN("Attempting to contact userspace log server...");
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r = dm_consult_userspace(uuid, lc->luid, DM_ULOG_CTR,
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lc->usr_argv_str,
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strlen(lc->usr_argv_str) + 1,
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NULL, NULL);
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if (!r)
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break;
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}
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DMINFO("Reconnected to userspace log server... DM_ULOG_CTR complete");
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r = dm_consult_userspace(uuid, lc->luid, DM_ULOG_RESUME, NULL,
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0, NULL, NULL);
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if (!r)
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goto retry;
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DMERR("Error trying to resume userspace log: %d", r);
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return -ESRCH;
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}
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static int build_constructor_string(struct dm_target *ti,
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unsigned argc, char **argv,
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char **ctr_str)
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{
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int i, str_size;
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char *str = NULL;
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*ctr_str = NULL;
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for (i = 0, str_size = 0; i < argc; i++)
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str_size += strlen(argv[i]) + 1; /* +1 for space between args */
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str_size += 20; /* Max number of chars in a printed u64 number */
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str = kzalloc(str_size, GFP_KERNEL);
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if (!str) {
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DMWARN("Unable to allocate memory for constructor string");
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return -ENOMEM;
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}
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str_size = sprintf(str, "%llu", (unsigned long long)ti->len);
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for (i = 0; i < argc; i++)
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str_size += sprintf(str + str_size, " %s", argv[i]);
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*ctr_str = str;
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return str_size;
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}
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/*
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* userspace_ctr
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*
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* argv contains:
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* <UUID> <other args>
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* Where 'other args' is the userspace implementation specific log
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* arguments. An example might be:
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* <UUID> clustered-disk <arg count> <log dev> <region_size> [[no]sync]
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*
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* So, this module will strip off the <UUID> for identification purposes
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* when communicating with userspace about a log; but will pass on everything
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* else.
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*/
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static int userspace_ctr(struct dm_dirty_log *log, struct dm_target *ti,
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unsigned argc, char **argv)
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{
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int r = 0;
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int str_size;
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char *ctr_str = NULL;
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struct log_c *lc = NULL;
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uint64_t rdata;
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size_t rdata_size = sizeof(rdata);
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char *devices_rdata = NULL;
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size_t devices_rdata_size = DM_NAME_LEN;
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if (argc < 3) {
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DMWARN("Too few arguments to userspace dirty log");
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return -EINVAL;
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}
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lc = kzalloc(sizeof(*lc), GFP_KERNEL);
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if (!lc) {
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DMWARN("Unable to allocate userspace log context.");
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return -ENOMEM;
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}
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/* The ptr value is sufficient for local unique id */
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lc->luid = (unsigned long)lc;
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lc->ti = ti;
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if (strlen(argv[0]) > (DM_UUID_LEN - 1)) {
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DMWARN("UUID argument too long.");
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kfree(lc);
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return -EINVAL;
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}
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strncpy(lc->uuid, argv[0], DM_UUID_LEN);
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spin_lock_init(&lc->flush_lock);
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INIT_LIST_HEAD(&lc->mark_list);
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INIT_LIST_HEAD(&lc->clear_list);
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str_size = build_constructor_string(ti, argc - 1, argv + 1, &ctr_str);
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if (str_size < 0) {
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kfree(lc);
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return str_size;
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}
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devices_rdata = kzalloc(devices_rdata_size, GFP_KERNEL);
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if (!devices_rdata) {
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DMERR("Failed to allocate memory for device information");
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r = -ENOMEM;
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goto out;
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}
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/*
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* Send table string and get back any opened device.
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*/
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r = dm_consult_userspace(lc->uuid, lc->luid, DM_ULOG_CTR,
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ctr_str, str_size,
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devices_rdata, &devices_rdata_size);
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if (r < 0) {
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if (r == -ESRCH)
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DMERR("Userspace log server not found");
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else
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DMERR("Userspace log server failed to create log");
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goto out;
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}
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/* Since the region size does not change, get it now */
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rdata_size = sizeof(rdata);
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r = dm_consult_userspace(lc->uuid, lc->luid, DM_ULOG_GET_REGION_SIZE,
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NULL, 0, (char *)&rdata, &rdata_size);
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if (r) {
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DMERR("Failed to get region size of dirty log");
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goto out;
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}
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lc->region_size = (uint32_t)rdata;
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lc->region_count = dm_sector_div_up(ti->len, lc->region_size);
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if (devices_rdata_size) {
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if (devices_rdata[devices_rdata_size - 1] != '\0') {
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DMERR("DM_ULOG_CTR device return string not properly terminated");
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r = -EINVAL;
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goto out;
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}
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r = dm_get_device(ti, devices_rdata,
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dm_table_get_mode(ti->table), &lc->log_dev);
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if (r)
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DMERR("Failed to register %s with device-mapper",
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devices_rdata);
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}
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out:
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kfree(devices_rdata);
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if (r) {
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kfree(lc);
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kfree(ctr_str);
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} else {
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lc->usr_argv_str = ctr_str;
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lc->usr_argc = argc;
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log->context = lc;
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}
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return r;
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}
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static void userspace_dtr(struct dm_dirty_log *log)
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{
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struct log_c *lc = log->context;
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(void) dm_consult_userspace(lc->uuid, lc->luid, DM_ULOG_DTR,
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NULL, 0,
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NULL, NULL);
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if (lc->log_dev)
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dm_put_device(lc->ti, lc->log_dev);
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kfree(lc->usr_argv_str);
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kfree(lc);
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return;
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}
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static int userspace_presuspend(struct dm_dirty_log *log)
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{
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int r;
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struct log_c *lc = log->context;
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r = dm_consult_userspace(lc->uuid, lc->luid, DM_ULOG_PRESUSPEND,
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NULL, 0,
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NULL, NULL);
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return r;
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}
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static int userspace_postsuspend(struct dm_dirty_log *log)
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{
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int r;
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struct log_c *lc = log->context;
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r = dm_consult_userspace(lc->uuid, lc->luid, DM_ULOG_POSTSUSPEND,
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NULL, 0,
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NULL, NULL);
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return r;
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}
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static int userspace_resume(struct dm_dirty_log *log)
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{
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int r;
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struct log_c *lc = log->context;
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lc->in_sync_hint = 0;
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r = dm_consult_userspace(lc->uuid, lc->luid, DM_ULOG_RESUME,
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NULL, 0,
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NULL, NULL);
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return r;
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}
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static uint32_t userspace_get_region_size(struct dm_dirty_log *log)
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{
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struct log_c *lc = log->context;
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return lc->region_size;
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}
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/*
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* userspace_is_clean
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*
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* Check whether a region is clean. If there is any sort of
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* failure when consulting the server, we return not clean.
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*
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* Returns: 1 if clean, 0 otherwise
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*/
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static int userspace_is_clean(struct dm_dirty_log *log, region_t region)
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{
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int r;
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uint64_t region64 = (uint64_t)region;
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int64_t is_clean;
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size_t rdata_size;
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struct log_c *lc = log->context;
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rdata_size = sizeof(is_clean);
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r = userspace_do_request(lc, lc->uuid, DM_ULOG_IS_CLEAN,
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(char *)®ion64, sizeof(region64),
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(char *)&is_clean, &rdata_size);
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return (r) ? 0 : (int)is_clean;
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}
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/*
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* userspace_in_sync
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*
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* Check if the region is in-sync. If there is any sort
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* of failure when consulting the server, we assume that
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* the region is not in sync.
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*
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* If 'can_block' is set, return immediately
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*
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* Returns: 1 if in-sync, 0 if not-in-sync, -EWOULDBLOCK
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*/
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static int userspace_in_sync(struct dm_dirty_log *log, region_t region,
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int can_block)
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{
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int r;
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uint64_t region64 = region;
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int64_t in_sync;
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size_t rdata_size;
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struct log_c *lc = log->context;
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/*
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* We can never respond directly - even if in_sync_hint is
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* set. This is because another machine could see a device
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* failure and mark the region out-of-sync. If we don't go
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* to userspace to ask, we might think the region is in-sync
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* and allow a read to pick up data that is stale. (This is
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* very unlikely if a device actually fails; but it is very
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* likely if a connection to one device from one machine fails.)
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*
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* There still might be a problem if the mirror caches the region
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* state as in-sync... but then this call would not be made. So,
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* that is a mirror problem.
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*/
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if (!can_block)
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return -EWOULDBLOCK;
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rdata_size = sizeof(in_sync);
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r = userspace_do_request(lc, lc->uuid, DM_ULOG_IN_SYNC,
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(char *)®ion64, sizeof(region64),
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(char *)&in_sync, &rdata_size);
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return (r) ? 0 : (int)in_sync;
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}
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static int flush_one_by_one(struct log_c *lc, struct list_head *flush_list)
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{
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int r = 0;
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struct flush_entry *fe;
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list_for_each_entry(fe, flush_list, list) {
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r = userspace_do_request(lc, lc->uuid, fe->type,
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(char *)&fe->region,
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sizeof(fe->region),
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NULL, NULL);
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if (r)
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break;
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}
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return r;
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}
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static int flush_by_group(struct log_c *lc, struct list_head *flush_list)
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{
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int r = 0;
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int count;
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uint32_t type = 0;
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struct flush_entry *fe, *tmp_fe;
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LIST_HEAD(tmp_list);
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uint64_t group[MAX_FLUSH_GROUP_COUNT];
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/*
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* Group process the requests
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*/
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while (!list_empty(flush_list)) {
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count = 0;
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list_for_each_entry_safe(fe, tmp_fe, flush_list, list) {
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group[count] = fe->region;
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count++;
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list_move(&fe->list, &tmp_list);
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type = fe->type;
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if (count >= MAX_FLUSH_GROUP_COUNT)
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break;
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}
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r = userspace_do_request(lc, lc->uuid, type,
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(char *)(group),
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count * sizeof(uint64_t),
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NULL, NULL);
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if (r) {
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/* Group send failed. Attempt one-by-one. */
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list_splice_init(&tmp_list, flush_list);
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r = flush_one_by_one(lc, flush_list);
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break;
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}
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}
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/*
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* Must collect flush_entrys that were successfully processed
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* as a group so that they will be free'd by the caller.
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*/
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list_splice_init(&tmp_list, flush_list);
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return r;
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}
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/*
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* userspace_flush
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*
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* This function is ok to block.
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* The flush happens in two stages. First, it sends all
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* clear/mark requests that are on the list. Then it
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* tells the server to commit them. This gives the
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* server a chance to optimise the commit, instead of
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* doing it for every request.
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*
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* Additionally, we could implement another thread that
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* sends the requests up to the server - reducing the
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* load on flush. Then the flush would have less in
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* the list and be responsible for the finishing commit.
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*
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* Returns: 0 on success, < 0 on failure
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*/
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static int userspace_flush(struct dm_dirty_log *log)
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{
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int r = 0;
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unsigned long flags;
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struct log_c *lc = log->context;
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LIST_HEAD(mark_list);
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LIST_HEAD(clear_list);
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struct flush_entry *fe, *tmp_fe;
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spin_lock_irqsave(&lc->flush_lock, flags);
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list_splice_init(&lc->mark_list, &mark_list);
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list_splice_init(&lc->clear_list, &clear_list);
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spin_unlock_irqrestore(&lc->flush_lock, flags);
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if (list_empty(&mark_list) && list_empty(&clear_list))
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return 0;
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r = flush_by_group(lc, &mark_list);
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if (r)
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goto fail;
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r = flush_by_group(lc, &clear_list);
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if (r)
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goto fail;
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r = userspace_do_request(lc, lc->uuid, DM_ULOG_FLUSH,
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NULL, 0, NULL, NULL);
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fail:
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/*
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* We can safely remove these entries, even if failure.
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* Calling code will receive an error and will know that
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* the log facility has failed.
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*/
|
|
list_for_each_entry_safe(fe, tmp_fe, &mark_list, list) {
|
|
list_del(&fe->list);
|
|
mempool_free(fe, flush_entry_pool);
|
|
}
|
|
list_for_each_entry_safe(fe, tmp_fe, &clear_list, list) {
|
|
list_del(&fe->list);
|
|
mempool_free(fe, flush_entry_pool);
|
|
}
|
|
|
|
if (r)
|
|
dm_table_event(lc->ti->table);
|
|
|
|
return r;
|
|
}
|
|
|
|
/*
|
|
* userspace_mark_region
|
|
*
|
|
* This function should avoid blocking unless absolutely required.
|
|
* (Memory allocation is valid for blocking.)
|
|
*/
|
|
static void userspace_mark_region(struct dm_dirty_log *log, region_t region)
|
|
{
|
|
unsigned long flags;
|
|
struct log_c *lc = log->context;
|
|
struct flush_entry *fe;
|
|
|
|
/* Wait for an allocation, but _never_ fail */
|
|
fe = mempool_alloc(flush_entry_pool, GFP_NOIO);
|
|
BUG_ON(!fe);
|
|
|
|
spin_lock_irqsave(&lc->flush_lock, flags);
|
|
fe->type = DM_ULOG_MARK_REGION;
|
|
fe->region = region;
|
|
list_add(&fe->list, &lc->mark_list);
|
|
spin_unlock_irqrestore(&lc->flush_lock, flags);
|
|
|
|
return;
|
|
}
|
|
|
|
/*
|
|
* userspace_clear_region
|
|
*
|
|
* This function must not block.
|
|
* So, the alloc can't block. In the worst case, it is ok to
|
|
* fail. It would simply mean we can't clear the region.
|
|
* Does nothing to current sync context, but does mean
|
|
* the region will be re-sync'ed on a reload of the mirror
|
|
* even though it is in-sync.
|
|
*/
|
|
static void userspace_clear_region(struct dm_dirty_log *log, region_t region)
|
|
{
|
|
unsigned long flags;
|
|
struct log_c *lc = log->context;
|
|
struct flush_entry *fe;
|
|
|
|
/*
|
|
* If we fail to allocate, we skip the clearing of
|
|
* the region. This doesn't hurt us in any way, except
|
|
* to cause the region to be resync'ed when the
|
|
* device is activated next time.
|
|
*/
|
|
fe = mempool_alloc(flush_entry_pool, GFP_ATOMIC);
|
|
if (!fe) {
|
|
DMERR("Failed to allocate memory to clear region.");
|
|
return;
|
|
}
|
|
|
|
spin_lock_irqsave(&lc->flush_lock, flags);
|
|
fe->type = DM_ULOG_CLEAR_REGION;
|
|
fe->region = region;
|
|
list_add(&fe->list, &lc->clear_list);
|
|
spin_unlock_irqrestore(&lc->flush_lock, flags);
|
|
|
|
return;
|
|
}
|
|
|
|
/*
|
|
* userspace_get_resync_work
|
|
*
|
|
* Get a region that needs recovery. It is valid to return
|
|
* an error for this function.
|
|
*
|
|
* Returns: 1 if region filled, 0 if no work, <0 on error
|
|
*/
|
|
static int userspace_get_resync_work(struct dm_dirty_log *log, region_t *region)
|
|
{
|
|
int r;
|
|
size_t rdata_size;
|
|
struct log_c *lc = log->context;
|
|
struct {
|
|
int64_t i; /* 64-bit for mix arch compatibility */
|
|
region_t r;
|
|
} pkg;
|
|
|
|
if (lc->in_sync_hint >= lc->region_count)
|
|
return 0;
|
|
|
|
rdata_size = sizeof(pkg);
|
|
r = userspace_do_request(lc, lc->uuid, DM_ULOG_GET_RESYNC_WORK,
|
|
NULL, 0,
|
|
(char *)&pkg, &rdata_size);
|
|
|
|
*region = pkg.r;
|
|
return (r) ? r : (int)pkg.i;
|
|
}
|
|
|
|
/*
|
|
* userspace_set_region_sync
|
|
*
|
|
* Set the sync status of a given region. This function
|
|
* must not fail.
|
|
*/
|
|
static void userspace_set_region_sync(struct dm_dirty_log *log,
|
|
region_t region, int in_sync)
|
|
{
|
|
int r;
|
|
struct log_c *lc = log->context;
|
|
struct {
|
|
region_t r;
|
|
int64_t i;
|
|
} pkg;
|
|
|
|
pkg.r = region;
|
|
pkg.i = (int64_t)in_sync;
|
|
|
|
r = userspace_do_request(lc, lc->uuid, DM_ULOG_SET_REGION_SYNC,
|
|
(char *)&pkg, sizeof(pkg),
|
|
NULL, NULL);
|
|
|
|
/*
|
|
* It would be nice to be able to report failures.
|
|
* However, it is easy emough to detect and resolve.
|
|
*/
|
|
return;
|
|
}
|
|
|
|
/*
|
|
* userspace_get_sync_count
|
|
*
|
|
* If there is any sort of failure when consulting the server,
|
|
* we assume that the sync count is zero.
|
|
*
|
|
* Returns: sync count on success, 0 on failure
|
|
*/
|
|
static region_t userspace_get_sync_count(struct dm_dirty_log *log)
|
|
{
|
|
int r;
|
|
size_t rdata_size;
|
|
uint64_t sync_count;
|
|
struct log_c *lc = log->context;
|
|
|
|
rdata_size = sizeof(sync_count);
|
|
r = userspace_do_request(lc, lc->uuid, DM_ULOG_GET_SYNC_COUNT,
|
|
NULL, 0,
|
|
(char *)&sync_count, &rdata_size);
|
|
|
|
if (r)
|
|
return 0;
|
|
|
|
if (sync_count >= lc->region_count)
|
|
lc->in_sync_hint = lc->region_count;
|
|
|
|
return (region_t)sync_count;
|
|
}
|
|
|
|
/*
|
|
* userspace_status
|
|
*
|
|
* Returns: amount of space consumed
|
|
*/
|
|
static int userspace_status(struct dm_dirty_log *log, status_type_t status_type,
|
|
char *result, unsigned maxlen)
|
|
{
|
|
int r = 0;
|
|
char *table_args;
|
|
size_t sz = (size_t)maxlen;
|
|
struct log_c *lc = log->context;
|
|
|
|
switch (status_type) {
|
|
case STATUSTYPE_INFO:
|
|
r = userspace_do_request(lc, lc->uuid, DM_ULOG_STATUS_INFO,
|
|
NULL, 0,
|
|
result, &sz);
|
|
|
|
if (r) {
|
|
sz = 0;
|
|
DMEMIT("%s 1 COM_FAILURE", log->type->name);
|
|
}
|
|
break;
|
|
case STATUSTYPE_TABLE:
|
|
sz = 0;
|
|
table_args = strchr(lc->usr_argv_str, ' ');
|
|
BUG_ON(!table_args); /* There will always be a ' ' */
|
|
table_args++;
|
|
|
|
DMEMIT("%s %u %s %s ", log->type->name, lc->usr_argc,
|
|
lc->uuid, table_args);
|
|
break;
|
|
}
|
|
return (r) ? 0 : (int)sz;
|
|
}
|
|
|
|
/*
|
|
* userspace_is_remote_recovering
|
|
*
|
|
* Returns: 1 if region recovering, 0 otherwise
|
|
*/
|
|
static int userspace_is_remote_recovering(struct dm_dirty_log *log,
|
|
region_t region)
|
|
{
|
|
int r;
|
|
uint64_t region64 = region;
|
|
struct log_c *lc = log->context;
|
|
static unsigned long long limit;
|
|
struct {
|
|
int64_t is_recovering;
|
|
uint64_t in_sync_hint;
|
|
} pkg;
|
|
size_t rdata_size = sizeof(pkg);
|
|
|
|
/*
|
|
* Once the mirror has been reported to be in-sync,
|
|
* it will never again ask for recovery work. So,
|
|
* we can safely say there is not a remote machine
|
|
* recovering if the device is in-sync. (in_sync_hint
|
|
* must be reset at resume time.)
|
|
*/
|
|
if (region < lc->in_sync_hint)
|
|
return 0;
|
|
else if (jiffies < limit)
|
|
return 1;
|
|
|
|
limit = jiffies + (HZ / 4);
|
|
r = userspace_do_request(lc, lc->uuid, DM_ULOG_IS_REMOTE_RECOVERING,
|
|
(char *)®ion64, sizeof(region64),
|
|
(char *)&pkg, &rdata_size);
|
|
if (r)
|
|
return 1;
|
|
|
|
lc->in_sync_hint = pkg.in_sync_hint;
|
|
|
|
return (int)pkg.is_recovering;
|
|
}
|
|
|
|
static struct dm_dirty_log_type _userspace_type = {
|
|
.name = "userspace",
|
|
.module = THIS_MODULE,
|
|
.ctr = userspace_ctr,
|
|
.dtr = userspace_dtr,
|
|
.presuspend = userspace_presuspend,
|
|
.postsuspend = userspace_postsuspend,
|
|
.resume = userspace_resume,
|
|
.get_region_size = userspace_get_region_size,
|
|
.is_clean = userspace_is_clean,
|
|
.in_sync = userspace_in_sync,
|
|
.flush = userspace_flush,
|
|
.mark_region = userspace_mark_region,
|
|
.clear_region = userspace_clear_region,
|
|
.get_resync_work = userspace_get_resync_work,
|
|
.set_region_sync = userspace_set_region_sync,
|
|
.get_sync_count = userspace_get_sync_count,
|
|
.status = userspace_status,
|
|
.is_remote_recovering = userspace_is_remote_recovering,
|
|
};
|
|
|
|
static int __init userspace_dirty_log_init(void)
|
|
{
|
|
int r = 0;
|
|
|
|
flush_entry_pool = mempool_create(100, flush_entry_alloc,
|
|
flush_entry_free, NULL);
|
|
|
|
if (!flush_entry_pool) {
|
|
DMWARN("Unable to create flush_entry_pool: No memory.");
|
|
return -ENOMEM;
|
|
}
|
|
|
|
r = dm_ulog_tfr_init();
|
|
if (r) {
|
|
DMWARN("Unable to initialize userspace log communications");
|
|
mempool_destroy(flush_entry_pool);
|
|
return r;
|
|
}
|
|
|
|
r = dm_dirty_log_type_register(&_userspace_type);
|
|
if (r) {
|
|
DMWARN("Couldn't register userspace dirty log type");
|
|
dm_ulog_tfr_exit();
|
|
mempool_destroy(flush_entry_pool);
|
|
return r;
|
|
}
|
|
|
|
DMINFO("version " DM_LOG_USERSPACE_VSN " loaded");
|
|
return 0;
|
|
}
|
|
|
|
static void __exit userspace_dirty_log_exit(void)
|
|
{
|
|
dm_dirty_log_type_unregister(&_userspace_type);
|
|
dm_ulog_tfr_exit();
|
|
mempool_destroy(flush_entry_pool);
|
|
|
|
DMINFO("version " DM_LOG_USERSPACE_VSN " unloaded");
|
|
return;
|
|
}
|
|
|
|
module_init(userspace_dirty_log_init);
|
|
module_exit(userspace_dirty_log_exit);
|
|
|
|
MODULE_DESCRIPTION(DM_NAME " userspace dirty log link");
|
|
MODULE_AUTHOR("Jonathan Brassow <dm-devel@redhat.com>");
|
|
MODULE_LICENSE("GPL");
|