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-rw-r--r--src/server/job.c772
1 files changed, 0 insertions, 772 deletions
diff --git a/src/server/job.c b/src/server/job.c
deleted file mode 100644
index 31f577b..0000000
--- a/src/server/job.c
+++ /dev/null
@@ -1,772 +0,0 @@
-#include "job.h"
-#include "saveload.h"
-#include "helper.h"
-#include "memlog.h"
-#include "rpc.h"
-
-#include <stdint.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <unistd.h>
-#include <string.h>
-#include <fcntl.h>
-#include <sys/ioctl.h>
-#include <linux/fs.h>
-#include <pthread.h>
-#include "sockhelper.h"
-
-#include <glib/gslist.h>
-
-#include <libxml/parser.h>
-#include <libxml/xpath.h>
-#include "xmlutil.h"
-#include "../config.h"
-
-#define DEV_STRLEN 12 // INCLUDING NULLCHAR (increase to 13 if you need more than 100 (0-99) devices)
-#define MAX_NUM_DEVICES_TO_CHECK 100
-
-#ifndef FALSE
-#define FALSE (0)
-#endif
-
-#ifndef TRUE
-#define TRUE (!FALSE)
-#endif
-
-typedef struct
-{
- char available;
- char name[DEV_STRLEN];
-} device_t;
-
-// "/dev/dnbdXX" == 11 bytes per device + nullchar = 12
-static device_t *devices = NULL;
-static int num_devices = 0;
-static char keep_running = TRUE;
-
-// Private functions
-static char *get_free_device();
-static void return_free_device(char *name);
-static void connect_proxy_images();
-static void query_servers();
-static char *create_cache_filename(char *name, int rid, char *buffer, int maxlen);
-static void add_alt_server(dnbd3_image_t *image, dnbd3_host_t *host);
-static void remove_alt_server(dnbd3_trusted_server_t *server);
-static void dnbd3_update_atimes(time_t now);
-
-//
-
-void *dnbd3_job_thread(void *data)
-{
- int i, j;
- // Determine number of available dnbd3 devices, which are needed for proxy mode
- char dev[DEV_STRLEN];
- for (i = 0; i < MAX_NUM_DEVICES_TO_CHECK; ++i)
- {
- snprintf(dev, DEV_STRLEN, "/dev/dnbd%d", i);
- if (access(dev, W_OK | R_OK)) // Need RW access to device to read and do ioctl
- continue;
- ++num_devices;
- }
- if (num_devices > 0)
- {
- devices = calloc(num_devices, sizeof(*devices));
- for (i = 0, j = 0; i < MAX_NUM_DEVICES_TO_CHECK; ++i)
- {
- memset(dev, 0, DEV_STRLEN);
- snprintf(dev, DEV_STRLEN, "/dev/dnbd%d", i);
- if (access(dev, W_OK | R_OK))
- continue;
- if (j >= num_devices) // More available devices during second iteration? :-(
- break;
- memcpy(devices[j].name, dev, DEV_STRLEN);
- devices[j].available = TRUE;
- ++j;
- }
- num_devices = j;
- }
- memlogf("[INFO] %d available dnbd3 devices for proxy mode", num_devices);
- //
- time_t next_delete_invocation = 0;
- //
- // Job/Watchdog mainloop
- while (keep_running)
- {
- const time_t starttime = time(NULL);
- //
- // Update image atime
- dnbd3_update_atimes(starttime);
- // Call image deletion function if last call is more than 5 minutes ago
- if (starttime > next_delete_invocation)
- {
- next_delete_invocation = starttime + 300;
- dnbd3_exec_delete(TRUE);
- }
- // Check for proxied images that have not been set up yet
- connect_proxy_images();
- // TODO: Replicate proxied images (limited bandwidth)
- // Query other servers for new images/status/...
- query_servers();
- // TODO: Switch server of dnbd device based on more sophisticated inputs than just rtt
- // Calc sleep timeout for next iteration
- sleep(30 - (time(NULL) - starttime)); // Sleep 30 seconds, but account for the time it took to execute the loop
- }
- //
- free(devices);
- devices = NULL;
- pthread_exit(NULL);
- return NULL;
-}
-
-void dnbd3_job_shutdown()
-{
- keep_running = FALSE;
-}
-
-static void connect_proxy_images()
-{
- int s, n;
- dnbd3_server_entry_t servers[NUMBER_SERVERS];
- char imagename[1000];
- int rid;
- dnbd3_ioctl_t msg;
- memset(&msg, 0, sizeof(dnbd3_ioctl_t));
- msg.len = (uint16_t)sizeof(dnbd3_ioctl_t);
- msg.read_ahead_kb = DEFAULT_READ_AHEAD_KB;
- msg.is_server = TRUE;
- for (n = 0 ;; ++n) // Iterate over all images
- {
- pthread_spin_lock(&_spinlock);
- dnbd3_image_t *image = g_slist_nth_data(_dnbd3_images, n);
- if (image == NULL)
- { // End of list reached
- pthread_spin_unlock(&_spinlock);
- break;
- }
- if (image->working && image->cache_map && image->file)
- { // Image is relayed and already connected, check if cache is complete
- int complete = TRUE, j;
- const int map_len_bytes = IMGSIZE_TO_MAPBYTES(image->filesize);
- for (j = 0; j < map_len_bytes - 1; ++j)
- {
- if (image->cache_map[j] != 0xFF)
- {
- complete = FALSE;
- break;
- }
- }
- if (complete) // Every block except the last one is complete
- { // Last one might need extra treatment if it's not a full byte
- const int blocks_in_last_byte = (image->filesize >> 12) & 7;
- uint8_t last_byte = 0;
- if (blocks_in_last_byte == 0)
- last_byte = 0xFF;
- else
- for (j = 0; j < blocks_in_last_byte; ++j)
- last_byte |= (1 << j);
- complete = ((image->cache_map[map_len_bytes - 1] & last_byte) == last_byte);
- }
- if (!complete) // Image is not complete, finished handling it
- {
- pthread_spin_unlock(&_spinlock);
- continue;
- }
- // Image is 100% cached, disconnect dnbd3 device
- memlogf("[INFO] Disconnecting %s because local copy of %s is complete.", image->file, image->config_group);
- int dh = open(image->file, O_RDONLY);
- if (dh < 0)
- memlogf("[ERROR] Could not open() device '%s'", image->file);
- else
- {
- if (ioctl(dh, IOCTL_CLOSE, (void*)0) != 0)
- memlogf("[ERROR] Could not IOCTL_CLOSE device '%s'", image->file);
- else
- return_free_device(image->file);
- close(dh);
- }
- free(image->file);
- image->file = NULL;
- pthread_spin_unlock(&_spinlock);
- continue;
- }
- if (image->working || image->file || image->low_name == NULL)
- { // Image is a local one, nothing to do
- pthread_spin_unlock(&_spinlock);
- continue;
- }
- // Image is relayed and not connected yet
- char *devname = get_free_device();
- if (devname == NULL)
- { // All devices busy, can't connect
- pthread_spin_unlock(&_spinlock);
- continue;
- }
- // Remember image information as the image pointer isn't
- // guaranteed to stay valid after unlocking
- snprintf(imagename, 1000, "%s", image->low_name);
- rid = image->rid;
- memcpy(servers, image->servers, sizeof(servers[0]) * NUMBER_SERVERS);
- pthread_spin_unlock(&_spinlock);
- int dh = open(devname, O_RDWR);
- if (dh < 0) // Open device so we can issue ioctls to it
- {
- pthread_spin_lock(&_spinlock);
- return_free_device(devname); // Failed :-(
- pthread_spin_unlock(&_spinlock);
- continue;
- }
- for (s = 0; s < NUMBER_SERVERS; ++s)
- { // Try to connect to any of the alt servers known for that image
- if (servers[s].host.type == 0)
- continue;
- // connect device
- printf("[DEBUG] Connecting device....\n");
- msg.host = servers[s].host;
- msg.imgname = imagename;
- msg.imgnamelen = strlen(imagename);
- msg.rid = rid;
- if (ioctl(dh, IOCTL_OPEN, &msg) < 0)
- continue;
- printf("[DEBUG] Connected! Adding alt servers...\n");
- // connected. we manually add all known alt servers to this
- // device, so even if the initial server doesn't consider some
- // of those as trusted servers, they are still used for failover/load balancing
- for (++s; s < NUMBER_SERVERS; ++s)
- {
- if (servers[s].host.type == 0)
- continue;
- msg.host = servers[s].host;
- if (ioctl(dh, IOCTL_ADD_SRV, &msg) < 0)
- memlogf("[WARNING] Could not add alt server to proxy device");
- else
- printf("[DEBUG] Added an alt server\n");
- }
- printf("[DEBUG] Done, handling file size...\n");
- // LOCK + UPDATE
- int isworking = FALSE, alloc_cache = FALSE;
- pthread_spin_lock(&_spinlock);
- if (g_slist_find(_dnbd3_images, image) == NULL)
- { // Image not in list anymore, was deleted in meantime...
- if (ioctl(dh, IOCTL_CLOSE, &msg) < 0)
- memlogf("[WARNING] Could not close device after use - lost %s", devname);
- else
- return_free_device(devname);
- pthread_spin_unlock(&_spinlock);
- break;
- }
- // Image still exists
- image->file = strdup(devname);
- long long oct = 0;
- int t, ret;
- for (t = 0; t < 10 && dh >= 0; ++t)
- { // For some reason the getsize-ioctl might return 0 right after connecting
- // No idea why this happen. Maybe the IOCTL_OPEN call returns before the
- // connection is fully established, but I have no idea why.
- // So let's retry a couple of times if it fails.
- ret = ioctl(dh, BLKGETSIZE64, &oct);
- if (ret == 0 && oct > 0)
- break;
- close(dh);
- usleep(100 * 1000);
- dh = open(devname, O_RDONLY);
- }
- if (dh < 0 || ret != 0)
- memlogf("[ERROR] SIZE fail on %s (ret=%d, oct=%lld)", devname, ret, oct);
- else if (oct == 0)
- memlogf("[ERROR] Reported disk size is 0.");
- else if (image->filesize != 0 && image->filesize != oct)
- memlogf("[ERROR] Remote and local size of image do not match: %llu != %llu for %s", (unsigned long long)oct, (unsigned long long)image->filesize, image->low_name);
- else
- isworking = TRUE;
- image->filesize = (uint64_t)oct;
- if (image->cache_file != NULL && isworking && image->cache_map == NULL)
- {
- printf("[DEBUG] Image has cache file %s\n", image->cache_file);
- const int mapsize = IMGSIZE_TO_MAPBYTES(image->filesize);
- image->cache_map = calloc(mapsize, 1);
- off_t cachelen = -1;
- int ch = open(image->cache_file, O_RDONLY);
- if (ch >= 0)
- {
- cachelen = lseek(ch, 0, SEEK_END);
- close(ch);
- }
- if (ch < 0 || cachelen != image->filesize)
- alloc_cache = TRUE;
- if (cachelen == image->filesize)
- {
- char mapfile[strlen(image->cache_file) + 5];
- sprintf(mapfile, "%s.map", image->cache_file);
- int cmh = open(mapfile, O_RDONLY);
- if (cmh >= 0)
- {
- if (lseek(cmh, 0, SEEK_END) != mapsize)
- memlogf("[WARNING] Existing cache map has wrong size.");
- else
- {
- lseek(cmh, 0, SEEK_SET);
- read(cmh, image->cache_map, mapsize);
- printf("[DEBUG] Found existing cache file and map for %s\n", image->low_name);
- }
- close(cmh);
- }
- }
- }
- char cfname[1000] = {0};
- off_t fs = image->filesize;
- if (isworking && !(alloc_cache && image->cache_file))
- {
- image->working = TRUE;
- if (!image->cache_file) // This should be removed. proxy with no cache is completely pointless.
- memlogf("[WARNING] Proxy-Mode enabled without cache directory. This will most likely hurt performance.");
- goto continue_with_next_image;
- }
- snprintf(cfname, 1000, "%s", image->cache_file);
- pthread_spin_unlock(&_spinlock);
- if (isworking && *cfname)
- {
- int ch = open(cfname, O_WRONLY | O_CREAT, 0600);
- if (ch >= 0)
- {
- // Pre-allocate disk space
- // TODO: Check if this has a performance impact on the rest of the server (ie. client lag)
- // If so, do this gracefully by incrementing size and sleeping in between.
- printf("[DEBUG] Pre-allocating disk space...\n");
- lseek(ch, fs - 1, SEEK_SET);
- write(ch, &ch, 1);
- close(ch);
- printf("[DEBUG] Allocation complete.\n");
- pthread_spin_lock(&_spinlock);
- if (g_slist_find(_dnbd3_images, image) != NULL)
- {
- image->working = TRUE;
- memlogf("[INFO] Enabled relayed image %s (%lld)", image->low_name, (long long)fs);
- goto continue_with_next_image;
- }
- unlink(cfname);
- memlogf("[WARNING] Image has gone away");
- pthread_spin_unlock(&_spinlock);
- }
- else
- memlogf("[WARNING] Could not pre-allocate %s", cfname);
- }
- break;
- } // <-- end of loop over servers
- // If this point is reached, setting up replication was not successful,
- // so lock and free the filename allocated earlier, and return the device.
- pthread_spin_lock(&_spinlock);
- if (g_slist_find(_dnbd3_images, image) != NULL)
- {
- free(image->file);
- image->file = NULL;
- }
- return_free_device(devname);
-continue_with_next_image:
- pthread_spin_unlock(&_spinlock);
- close(dh);
- }
-}
-
-static void dnbd3_update_atimes(time_t now)
-{
- GSList *iterator;
- pthread_spin_lock(&_spinlock);
- for (iterator = _dnbd3_clients; iterator; iterator = iterator->next)
- {
- dnbd3_client_t *client = iterator->data;
- if (client && client->image && !client->is_server)
- client->image->atime = now;
- }
- pthread_spin_unlock(&_spinlock);
-}
-
-static void query_servers()
-{
- if (_trusted_servers == NULL)
- return;
- int client_sock, num;
- dnbd3_trusted_server_t *server;
- dnbd3_host_t host;
- char xmlbuffer[MAX_RPC_PAYLOAD];
- for (num = 0;; ++num)
- {
- // "Iterate" this way to prevent holding the lock for a long time,
- // although there is a very small chance to skip a server this way...
- pthread_spin_lock(&_spinlock);
- server = g_slist_nth_data(_trusted_servers, num);
- if (server == NULL)
- {
- pthread_spin_unlock(&_spinlock);
- break; // Done
- }
- host = server->host; // Copy host, in case server gets deleted by another thread while processing continues here
- pthread_spin_unlock(&_spinlock);
- // Connect
- host.port = htons(ntohs(host.port) + 1); // RPC port is client port + 1
- client_sock = sock_connect(&host, 800, 600);
- if (client_sock == -1)
- {
- char buf[100];
- if (host_to_string(&host, buf, 100))
- printf("[DEBUG] Could not connect to trusted server %s\n", buf);
- goto communication_error;
- }
- //
- // Send and receive info from server
- // Send message
- dnbd3_rpc_t header;
- header.cmd = htonl(RPC_IMG_LIST);
- header.size = 0;
- send(client_sock, (char *)&header, sizeof(header), 0);
- if (!recv_data(client_sock, &header, sizeof(header)))
- {
- printf("[DEBUG] Could not receive IMG_LIST header from a trusted server...\n");
- goto communication_error;
- }
- header.cmd = ntohl(header.cmd);
- header.size = ntohl(header.size);
- if (header.cmd != RPC_IMG_LIST)
- {
- printf("[DEBUG] Error. Reply from other server was cmd:%d, error:%d\n", (int)header.cmd, (int)-1);
- goto communication_error;
- }
- if (header.size > MAX_RPC_PAYLOAD)
- {
- memlogf("[WARNING] XML payload from other server exceeds MAX_RPC_PAYLOAD (%d > %d)", (int)header.size, (int)MAX_RPC_PAYLOAD);
- goto communication_error;
- }
- if (!recv_data(client_sock, xmlbuffer, header.size))
- {
- printf("[DEBUG] Error reading XML payload from other server.\n");
- goto communication_error;
- }
- close(client_sock);
- //
- // Process data, update server info, add/remove this server as alt server for images, replicate images, etc.
- xmlDocPtr doc = xmlReadMemory(xmlbuffer, header.size, "noname.xml", NULL, 0);
-
- if (doc == NULL)
- {
- memlogf("[WARNING] Could not parse XML data received by other server.");
- goto communication_error;
- }
- // Data seems ok
-
- xmlNodePtr cur;
- FOR_EACH_NODE(doc, "/data/images/image", cur)
- {
- if (cur->type != XML_ELEMENT_NODE)
- continue;
- NEW_POINTERLIST;
- char *image = XML_GETPROP(cur, "name");
- char *ridstr = XML_GETPROP(cur, "rid");
- char *sizestr = XML_GETPROP(cur, "size");
- if (!image || !ridstr || !sizestr)
- goto free_current_image;
- const int rid = atoi(ridstr);
- const long long size = atoll(sizestr);
- if (rid <= 0)
- {
- printf("[DEBUG] Ignoring remote image with rid %d\n", rid);
- goto free_current_image;
- }
- char *slash = strrchr(image, '/');
- if (slash == NULL)
- {
- printf("[DEBUG] Ignoring remote image with no '/' in name...\n");
- goto free_current_image;
- }
- else
- {
- *slash++ = '\0';
- if (!is_valid_namespace(image))
- {
- printf("[DEBUG] Ignoring remote image with invalid namespace '%s'\n", image);
- goto free_current_image;
- }
- if (!is_valid_imagename(slash))
- {
- printf("[DEBUG] Ignoring remote image with invalid name '%s'\n", slash);
- goto free_current_image;
- }
- snprintf(xmlbuffer, MAX_RPC_PAYLOAD, "%s/%s", image, slash);
- }
- // Image seems legit, check if there's a local copy
- dnbd3_namespace_t *trust;
- pthread_spin_lock(&_spinlock);
- trust = dnbd3_get_trust_level(&host, image);
- if (trust == NULL)
- { // Namespace of image is not trusted
- pthread_spin_unlock(&_spinlock);
- printf("[DEBUG] No NS match: '%s'\n", xmlbuffer);
- goto free_current_image;
- }
- char *sdel = XML_GETPROP(cur, "softdelete");
- char *hdel = XML_GETPROP(cur, "harddelete");
- const time_t softdelete = sdel ? atol(sdel) : 0;
- const time_t harddelete = hdel ? atol(hdel) : 0;
- dnbd3_image_t *local_image = dnbd3_get_image(xmlbuffer, rid, FALSE);
- if (local_image == NULL && trust->auto_replicate)
- {
- pthread_spin_unlock(&_spinlock);
- const time_t deadline = time(NULL) + 60;
- if ((softdelete != 0 && softdelete < deadline)
- || (harddelete != 0 && harddelete < deadline))
- { // Image is already about to be deleted, ignore it
- printf("[DEBUG] Not replicating old image: '%s'\n", xmlbuffer);
- goto free_current_image;
- }
- // Image is NEW, add it!
- dnbd3_image_t newimage;
- char cachefile[90];
- memset(&newimage, 0, sizeof(newimage));
- newimage.config_group = xmlbuffer;
- newimage.rid = rid;
- newimage.filesize = size;
- newimage.delete_hard = harddelete;
- newimage.delete_soft = softdelete;
- if (_cache_dir)
- {
- newimage.cache_file = create_cache_filename(xmlbuffer, rid, cachefile, 90);
- printf("[DEBUG] Cache file is %s\n", newimage.cache_file);
- }
- dnbd3_add_image(&newimage);
- pthread_spin_lock(&_spinlock);
- local_image = dnbd3_get_image(xmlbuffer, rid, FALSE);
- if (local_image)
- add_alt_server(local_image, &host);
- pthread_spin_unlock(&_spinlock);
- }
- else if (local_image != NULL)
- {
- // Image is already KNOWN, add alt server if appropriate
- const time_t deadline = time(NULL) + 60;
- if (softdelete == 0 || softdelete > deadline)
- {
- if (local_image->filesize == 0) // Size is unknown, just assume the trusted server got it right
- local_image->filesize = size;
- if (size != local_image->filesize)
- printf("[DEBUG] Ignoring remote image '%s' because it has a different size from the local version! (remote: %llu, local: %llu)\n", local_image->config_group, size, (unsigned long long)local_image->filesize);
- else
- add_alt_server(local_image, &host);
- }
- if (local_image->cache_file && trust->auto_replicate) {
- local_image->delete_hard = harddelete;
- local_image->delete_soft = softdelete;
- }
- pthread_spin_unlock(&_spinlock);
- }
- else
- {
- printf("[DEBUG] No NS match: '%s'\n", xmlbuffer);
- pthread_spin_unlock(&_spinlock);
- }
- // Cleanup
-free_current_image:
- FREE_POINTERLIST;
- } END_FOR_EACH;
-
-
- // ...
- xmlFreeDoc(doc);
- //
- continue;
-communication_error:
- if (client_sock != -1)
- close(client_sock);
- pthread_spin_lock(&_spinlock);
- if (g_slist_find(_trusted_servers, server))
- {
- if (server->unreachable < 10 && ++server->unreachable == 5)
- remove_alt_server(server);
- }
- pthread_spin_unlock(&_spinlock);
- }
-}
-
-static char *create_cache_filename(char *name, int rid, char *buffer, int maxlen)
-{
- if (_cache_dir == NULL)
- return NULL;
- size_t cdl = strlen(_cache_dir);
- if (maxlen < 15 + cdl)
- return NULL;
- if (strlen(name) + 16 + cdl < maxlen)
- snprintf(buffer, maxlen, "%s/%s_rid_%d.cache", _cache_dir, name, rid);
- else
- {
- char *slash = strrchr(name, '/');
- if (slash == NULL)
- {
- snprintf(buffer, maxlen - 17, "%s/%s", _cache_dir, name);
- snprintf(buffer + maxlen - 17, 17, "_rid_%d.cache", rid);
- }
- else
- {
- snprintf(buffer, maxlen, "%s/%s", _cache_dir, name);
- snprintf(buffer + cdl, maxlen - cdl, "%s_rid_%d.cache", slash, rid);
- }
- }
- char *ptr = buffer + cdl + 1;
- while (*ptr)
- {
- if (*ptr == '/' || *ptr < 32 || *ptr == ' ' || *ptr == '\\' || *ptr == '*' || *ptr == '?')
- *ptr = '_';
- ++ptr;
- }
- FILE *fh;
- while ((fh = fopen(buffer, "rb")))
- { // Alter file name as long as a file by that name already exists (el cheapo edition)
- fclose(fh);
- char *c = buffer + rand() % strlen(buffer);
- *c = rand() % 26 + 'A';
- }
- return buffer;
-}
-
-/**
- * !! Call this while holding the lock !!
- */
-static void add_alt_server(dnbd3_image_t *image, dnbd3_host_t *host)
-{
- int i;
- for (i = 0; i < NUMBER_SERVERS; ++i)
- {
- if (is_same_server(host, &image->servers[i].host))
- { // Alt server already known for this image
- if (image->servers[i].failures)
- { // It was disabled, re-enable and send info to clients
- image->servers[i].failures = 0;
- break;
- }
- else // Alt-Server already known and active, do nothing
- return;
- }
- }
- // Add to list if it wasn't in there
- if (i >= NUMBER_SERVERS)
- for (i = 0; i < NUMBER_SERVERS; ++i)
- {
- if (image->servers[i].host.type == 0)
- {
- image->servers[i].host = *host;
- image->servers[i].failures = 0;
- break;
- }
- }
- if (i >= NUMBER_SERVERS) // To many known alt servers already
- return;
- // Broadcast to connected clients. Note that 'i' now points to the new server
- printf("[DEBUG] Adding alt server to %s\n", image->low_name);
- GSList *itc;
- dnbd3_reply_t header;
- header.cmd = CMD_GET_SERVERS;
- header.magic = dnbd3_packet_magic;
- header.size = sizeof(dnbd3_server_entry_t);
- fixup_reply(header);
- for (itc = _dnbd3_clients; itc; itc = itc->next)
- {
- dnbd3_client_t *const client = itc->data;
- if (client->image == image)
- {
- // Don't send message directly as the lock is being held; instead, enqueue it
- NEW_BINSTRING(message, sizeof(header) + sizeof(image->servers[i]));
- memcpy(message->data, &header, sizeof(header));
- memcpy(message->data + sizeof(header), &image->servers[i], sizeof(image->servers[i]));
- client->sendqueue = g_slist_append(client->sendqueue, message);
- }
- }
-}
-
-/**
- * !! Call this while holding the lock !!
- */
-static void remove_alt_server(dnbd3_trusted_server_t *server)
-{
- GSList *iti, *itc;
- int i;
- dnbd3_reply_t header;
- header.cmd = CMD_GET_SERVERS;
- header.magic = dnbd3_packet_magic;
- header.size = sizeof(dnbd3_server_entry_t);
- fixup_reply(header);
- // Iterate over all images
- for (iti = _dnbd3_images; iti; iti = iti->next)
- {
- dnbd3_image_t *const image = iti->data;
- // Check if any alt_server for that image is the server to be removed
- for (i = 0; i < NUMBER_SERVERS; ++i)
- {
- if (is_same_server(&server->host, &image->servers[i].host))
- {
- // Remove server from that image and tell every connected client about it
- image->servers[i].failures = 1;
- for (itc = _dnbd3_clients; itc; itc = itc->next)
- {
- dnbd3_client_t *const client = itc->data;
- if (client->image == image)
- {
- // Don't send message directly as the lock is being held; instead, enqueue it
- NEW_BINSTRING(message, sizeof(header) + sizeof(image->servers[i]));
- memcpy(message->data, &header, sizeof(header));
- memcpy(message->data + sizeof(header), &image->servers[i], sizeof(image->servers[i]));
- client->sendqueue = g_slist_append(client->sendqueue, message);
- }
- }
- image->servers[i].host.type = 0;
- }
- }
- }
-}
-
-/**
- * Get full name of an available dnbd3 device, eg. /dev/dnbd4
- * Returned buffer is owned by this module, do not modify or free!
- * Returns NULL if all devices are in use
- */
-static char *get_free_device()
-{
- if (devices == NULL)
- return NULL;
- int i, c;
- char buffer[100];
- for (i = 0; i < num_devices; ++i)
- {
- if (!devices[i].available)
- continue;
- devices[i].available = FALSE;
- // Check sysfs if device is maybe already connected
- snprintf(buffer, 100, "/sys/devices/virtual/block/%s/net/cur_server_addr", devices[i].name + 5);
- FILE *f = fopen(buffer, "r");
- if (f == NULL)
- {
- printf("[DEBUG] Could not open %s - device marked as used.\n", buffer);
- continue;
- }
- c = fgetc(f);
- fclose(f);
- if (c > 0)
- {
- // Could read something, so the device is connected
- printf("[DEBUG] Free device %s is actually in use - marked as such.\n", devices[i].name);
- continue;
- }
- return devices[i].name;
- }
- memlogf("[WARNING] No more free dnbd3 devices - proxy mode probably affected.");
- return NULL;
-}
-
-static void return_free_device(char *name)
-{
- if (devices == NULL)
- return;
- int i;
- for (i = 0; i < num_devices; ++i)
- {
- if (devices[i].available || strcmp(devices[i].name, name) != 0)
- continue;
- devices[i].available = TRUE;
- break;
- }
-}
generated by cgit v1.2.3-55-g7522 (git 2.39.0) at 2024-05-29 05:41:25 +0200