shared/machine-pool: remove unnecessary check

[elogind.git] / src / shared / machine-pool.c

diff --git a/src/shared/machine-pool.c b/src/shared/machine-pool.c
index 7b17395d212b2bff7a82bd93b41f6c244739154f..e7671a3c5ecfbb46868fd7e8023c1dc111454f63 100644 (file)
--- a/src/shared/machine-pool.c
+++ b/src/shared/machine-pool.c
@@ -47,7 +47,7 @@ static int check_btrfs(void) {
         return F_TYPE_EQUAL(sfs.f_type, BTRFS_SUPER_MAGIC);
 }
 
-static int setup_machine_raw(sd_bus_error *error) {
+static int setup_machine_raw(uint64_t size, sd_bus_error *error) {
         _cleanup_free_ char *tmp = NULL;
         _cleanup_close_ int fd = -1;
         struct statvfs ss;
@@ -91,7 +91,7 @@ static int setup_machine_raw(sd_bus_error *error) {
                 goto fail;
         }
 
-        if (ftruncate(fd, VAR_LIB_MACHINES_SIZE_START) < 0) {
+        if (ftruncate(fd, size) < 0) {
                 r = sd_bus_error_set_errnof(error, errno, "Failed to enlarge /var/lib/machines.raw: %m");
                 goto fail;
         }
@@ -151,8 +151,7 @@ static int setup_machine_raw(sd_bus_error *error) {
         return r;
 
 fail:
-        if (tmp)
-                unlink_noerrno(tmp);
+        unlink_noerrno(tmp);
 
         if (pid > 1)
                 kill_and_sigcont(pid, SIGKILL);
@@ -160,7 +159,7 @@ fail:
         return r;
 }
 
-int setup_machine_directory(sd_bus_error *error) {
+int setup_machine_directory(uint64_t size, sd_bus_error *error) {
         _cleanup_release_lock_file_ LockFile lock_file = LOCK_FILE_INIT;
         struct loop_info64 info = {
                 .lo_flags = LO_FLAGS_AUTOCLEAR,
@@ -169,8 +168,15 @@ int setup_machine_directory(sd_bus_error *error) {
         _cleanup_free_ char* loopdev = NULL;
         char tmpdir[] = "/tmp/import-mount.XXXXXX", *mntdir = NULL;
         bool tmpdir_made = false, mntdir_made = false, mntdir_mounted = false;
+        char buf[FORMAT_BYTES_MAX];
         int r, nr = -1;
 
+        /* btrfs cannot handle file systems < 16M, hence use this as minimum */
+        if (size == (uint64_t) -1)
+                size = VAR_LIB_MACHINES_SIZE_START;
+        else if (size < 16*1024*1024)
+                size = 16*1024*1024;
+
         /* Make sure we only set the directory up once at a time */
         r = make_lock_file("/run/systemd/machines.lock", LOCK_EX, &lock_file);
         if (r < 0)
@@ -193,7 +199,7 @@ int setup_machine_directory(sd_bus_error *error) {
             dir_is_empty("/var/lib/machines") == 0)
                 return sd_bus_error_setf(error, SD_BUS_ERROR_INVALID_ARGS, "/var/lib/machines is not a btrfs file system. Operation is not supported on legacy file systems.");
 
-        fd = setup_machine_raw(error);
+        fd = setup_machine_raw(size, error);
         if (fd < 0)
                 return fd;
 
@@ -268,6 +274,10 @@ int setup_machine_directory(sd_bus_error *error) {
                 goto fail;
         }
 
+        (void) syncfs(fd);
+
+        log_info("Set up /var/lib/machines as btrfs loopback file system of size %s mounted on /var/lib/machines.raw.", format_bytes(buf, sizeof(buf), size));
+
         (void) umount2(mntdir, MNT_DETACH);
         (void) rmdir(mntdir);
         (void) rmdir(tmpdir);
@@ -293,3 +303,73 @@ fail:
 
         return r;
 }
+
+static int sync_path(const char *p) {
+        _cleanup_close_ int fd = -1;
+
+        fd = open(p, O_RDONLY|O_CLOEXEC|O_NOCTTY);
+        if (fd < 0)
+                return -errno;
+
+        if (syncfs(fd) < 0)
+                return -errno;
+
+        return 0;
+}
+
+int grow_machine_directory(void) {
+        char buf[FORMAT_BYTES_MAX];
+        struct statvfs a, b;
+        uint64_t old_size, new_size, max_add;
+        int r;
+
+        /* Ensure the disk space data is accurate */
+        sync_path("/var/lib/machines");
+        sync_path("/var/lib/machines.raw");
+
+        if (statvfs("/var/lib/machines.raw", &a) < 0)
+                return -errno;
+
+        if (statvfs("/var/lib/machines", &b) < 0)
+                return -errno;
+
+        /* Don't grow if not enough disk space is available on the host */
+        if (((uint64_t) a.f_bavail * (uint64_t) a.f_bsize) <= VAR_LIB_MACHINES_FREE_MIN)
+                return 0;
+
+        /* Don't grow if at least 1/3th of the fs is still free */
+        if (b.f_bavail > b.f_blocks / 3)
+                return 0;
+
+        /* Calculate how much we are willing to add at maximum */
+        max_add = ((uint64_t) a.f_bavail * (uint64_t) a.f_bsize) - VAR_LIB_MACHINES_FREE_MIN;
+
+        /* Calculate the old size */
+        old_size = (uint64_t) b.f_blocks * (uint64_t) b.f_bsize;
+
+        /* Calculate the new size as three times the size of what is used right now */
+        new_size = ((uint64_t) b.f_blocks - (uint64_t) b.f_bavail) * (uint64_t) b.f_bsize * 3;
+
+        /* Always, grow at least to the start size */
+        if (new_size < VAR_LIB_MACHINES_SIZE_START)
+                new_size = VAR_LIB_MACHINES_SIZE_START;
+
+        /* If the new size is smaller than the old size, don't grow */
+        if (new_size < old_size)
+                return 0;
+
+        /* Ensure we never add more than the maximum */
+        if (new_size > old_size + max_add)
+                new_size = old_size + max_add;
+
+        r = btrfs_resize_loopback("/var/lib/machines", new_size, true);
+        if (r <= 0)
+                return r;
+
+        r = btrfs_quota_limit("/var/lib/machines", new_size);
+        if (r < 0)
+                return r;
+
+        log_info("Grew /var/lib/machines btrfs loopback file system to %s.", format_bytes(buf, sizeof(buf), new_size));
+        return 1;
+}