static int control_mount(struct gfs2_sbd *sdp)
{
struct lm_lockstruct *ls = &sdp->sd_lockstruct;
uint32_t start_gen, block_gen, mount_gen, lvb_gen;
int mounted_mode;
int retries = 0;
int error;
memset(&ls->ls_mounted_lksb, 0, sizeof(struct dlm_lksb));
memset(&ls->ls_control_lksb, 0, sizeof(struct dlm_lksb));
memset(&ls->ls_control_lvb, 0, GDLM_LVB_SIZE);
ls->ls_control_lksb.sb_lvbptr = ls->ls_control_lvb;
init_completion(&ls->ls_sync_wait);
set_bit(DFL_BLOCK_LOCKS, &ls->ls_recover_flags);
error = control_lock(sdp, DLM_LOCK_NL, DLM_LKF_VALBLK);
if (error) {
fs_err(sdp, "control_mount control_lock NL error %d\n", error);
return error;
}
error = mounted_lock(sdp, DLM_LOCK_NL, 0);
if (error) {
fs_err(sdp, "control_mount mounted_lock NL error %d\n", error);
control_unlock(sdp);
return error;
}
mounted_mode = DLM_LOCK_NL;
restart:
if (retries++ && signal_pending(current)) {
error = -EINTR;
goto fail;
}
/*
* We always start with both locks in NL. control_lock is
* demoted to NL below so we don't need to do it here.
*/
if (mounted_mode != DLM_LOCK_NL) {
error = mounted_lock(sdp, DLM_LOCK_NL, DLM_LKF_CONVERT);
if (error)
goto fail;
mounted_mode = DLM_LOCK_NL;
}
/*
* Other nodes need to do some work in dlm recovery and gfs2_control
* before the recover_done and control_lock will be ready for us below.
* A delay here is not required but often avoids having to retry.
*/
msleep_interruptible(500);
/*
* Acquire control_lock in EX and mounted_lock in either EX or PR.
* control_lock lvb keeps track of any pending journal recoveries.
* mounted_lock indicates if any other nodes have the fs mounted.
*/
error = control_lock(sdp, DLM_LOCK_EX, DLM_LKF_CONVERT|DLM_LKF_NOQUEUE|DLM_LKF_VALBLK);
if (error == -EAGAIN) {
goto restart;
} else if (error) {
fs_err(sdp, "control_mount control_lock EX error %d\n", error);
goto fail;
}
error = mounted_lock(sdp, DLM_LOCK_EX, DLM_LKF_CONVERT|DLM_LKF_NOQUEUE);
if (!error) {
mounted_mode = DLM_LOCK_EX;
goto locks_done;
} else if (error != -EAGAIN) {
fs_err(sdp, "control_mount mounted_lock EX error %d\n", error);
goto fail;
}
error = mounted_lock(sdp, DLM_LOCK_PR, DLM_LKF_CONVERT|DLM_LKF_NOQUEUE);
if (!error) {
mounted_mode = DLM_LOCK_PR;
goto locks_done;
} else {
/* not even -EAGAIN should happen here */
fs_err(sdp, "control_mount mounted_lock PR error %d\n", error);
goto fail;
}
locks_done:
/*
* If we got both locks above in EX, then we're the first mounter.
* If not, then we need to wait for the control_lock lvb to be
* updated by other mounted nodes to reflect our mount generation.
*
* In simple first mounter cases, first mounter will see zero lvb_gen,
* but in cases where all existing nodes leave/fail before mounting
* nodes finish control_mount, then all nodes will be mounting and
* lvb_gen will be non-zero.
*/
control_lvb_read(ls, &lvb_gen, ls->ls_lvb_bits);
if (lvb_gen == 0xFFFFFFFF) {
/* special value to force mount attempts to fail */
fs_err(sdp, "control_mount control_lock disabled\n");
error = -EINVAL;
goto fail;
}
if (mounted_mode == DLM_LOCK_EX) {
/* first mounter, keep both EX while doing first recovery */
spin_lock(&ls->ls_recover_spin);
clear_bit(DFL_BLOCK_LOCKS, &ls->ls_recover_flags);
set_bit(DFL_MOUNT_DONE, &ls->ls_recover_flags);
set_bit(DFL_FIRST_MOUNT, &ls->ls_recover_flags);
spin_unlock(&ls->ls_recover_spin);
fs_info(sdp, "first mounter control generation %u\n", lvb_gen);
return 0;
}
error = control_lock(sdp, DLM_LOCK_NL, DLM_LKF_CONVERT);
if (error)
goto fail;
/*
* We are not first mounter, now we need to wait for the control_lock
* lvb generation to be >= the generation from our first recover_done
* and all lvb bits to be clear (no pending journal recoveries.)
*/
if (!all_jid_bits_clear(ls->ls_lvb_bits)) {
/* journals need recovery, wait until all are clear */
fs_info(sdp, "control_mount wait for journal recovery\n");
goto restart;
}
spin_lock(&ls->ls_recover_spin);
block_gen = ls->ls_recover_block;
start_gen = ls->ls_recover_start;
mount_gen = ls->ls_recover_mount;
if (lvb_gen < mount_gen) {
/* wait for mounted nodes to update control_lock lvb to our
generation, which might include new recovery bits set */
fs_info(sdp, "control_mount wait1 block %u start %u mount %u "
"lvb %u flags %lx\n", block_gen, start_gen, mount_gen,
lvb_gen, ls->ls_recover_flags);
spin_unlock(&ls->ls_recover_spin);
goto restart;
}
if (lvb_gen != start_gen) {
/* wait for mounted nodes to update control_lock lvb to the
latest recovery generation */
fs_info(sdp, "control_mount wait2 block %u start %u mount %u "
"lvb %u flags %lx\n", block_gen, start_gen, mount_gen,
lvb_gen, ls->ls_recover_flags);
spin_unlock(&ls->ls_recover_spin);
goto restart;
}
if (block_gen == start_gen) {
/* dlm recovery in progress, wait for it to finish */
fs_info(sdp, "control_mount wait3 block %u start %u mount %u "
"lvb %u flags %lx\n", block_gen, start_gen, mount_gen,
lvb_gen, ls->ls_recover_flags);
spin_unlock(&ls->ls_recover_spin);
goto restart;
}
clear_bit(DFL_BLOCK_LOCKS, &ls->ls_recover_flags);
set_bit(DFL_MOUNT_DONE, &ls->ls_recover_flags);
memset(ls->ls_recover_submit, 0, ls->ls_recover_size*sizeof(uint32_t));
memset(ls->ls_recover_result, 0, ls->ls_recover_size*sizeof(uint32_t));
spin_unlock(&ls->ls_recover_spin);
return 0;
fail:
mounted_unlock(sdp);
control_unlock(sdp);
return error;
}
static int control_mount(struct gfs2_sbd *sdp)
{
struct lm_lockstruct *ls = &sdp->sd_lockstruct;
char lvb_bits[GDLM_LVB_SIZE];
uint32_t start_gen, block_gen, mount_gen, lvb_gen;
int mounted_mode;
int retries = 0;
int error;
memset(&ls->ls_mounted_lksb, 0, sizeof(struct dlm_lksb));
memset(&ls->ls_control_lksb, 0, sizeof(struct dlm_lksb));
memset(&ls->ls_control_lvb, 0, GDLM_LVB_SIZE);
ls->ls_control_lksb.sb_lvbptr = ls->ls_control_lvb;
init_completion(&ls->ls_sync_wait);
set_bit(DFL_BLOCK_LOCKS, &ls->ls_recover_flags);
error = control_lock(sdp, DLM_LOCK_NL, DLM_LKF_VALBLK);
if (error) {
fs_err(sdp, "control_mount control_lock NL error %d\n", error);
return error;
}
error = mounted_lock(sdp, DLM_LOCK_NL, 0);
if (error) {
fs_err(sdp, "control_mount mounted_lock NL error %d\n", error);
control_unlock(sdp);
return error;
}
mounted_mode = DLM_LOCK_NL;
restart:
if (retries++ && signal_pending(current)) {
error = -EINTR;
goto fail;
}
if (mounted_mode != DLM_LOCK_NL) {
error = mounted_lock(sdp, DLM_LOCK_NL, DLM_LKF_CONVERT);
if (error)
goto fail;
mounted_mode = DLM_LOCK_NL;
}
msleep_interruptible(500);
error = control_lock(sdp, DLM_LOCK_EX, DLM_LKF_CONVERT|DLM_LKF_NOQUEUE|DLM_LKF_VALBLK);
if (error == -EAGAIN) {
goto restart;
} else if (error) {
fs_err(sdp, "control_mount control_lock EX error %d\n", error);
goto fail;
}
error = mounted_lock(sdp, DLM_LOCK_EX, DLM_LKF_CONVERT|DLM_LKF_NOQUEUE);
if (!error) {
mounted_mode = DLM_LOCK_EX;
goto locks_done;
} else if (error != -EAGAIN) {
fs_err(sdp, "control_mount mounted_lock EX error %d\n", error);
goto fail;
}
error = mounted_lock(sdp, DLM_LOCK_PR, DLM_LKF_CONVERT|DLM_LKF_NOQUEUE);
if (!error) {
mounted_mode = DLM_LOCK_PR;
goto locks_done;
} else {
fs_err(sdp, "control_mount mounted_lock PR error %d\n", error);
goto fail;
}
locks_done:
control_lvb_read(ls, &lvb_gen, lvb_bits);
if (lvb_gen == 0xFFFFFFFF) {
fs_err(sdp, "control_mount control_lock disabled\n");
error = -EINVAL;
goto fail;
}
if (mounted_mode == DLM_LOCK_EX) {
spin_lock(&ls->ls_recover_spin);
clear_bit(DFL_BLOCK_LOCKS, &ls->ls_recover_flags);
set_bit(DFL_MOUNT_DONE, &ls->ls_recover_flags);
set_bit(DFL_FIRST_MOUNT, &ls->ls_recover_flags);
spin_unlock(&ls->ls_recover_spin);
fs_info(sdp, "first mounter control generation %u\n", lvb_gen);
return 0;
}
error = control_lock(sdp, DLM_LOCK_NL, DLM_LKF_CONVERT);
if (error)
goto fail;
if (!all_jid_bits_clear(lvb_bits)) {
fs_info(sdp, "control_mount wait for journal recovery\n");
goto restart;
}
spin_lock(&ls->ls_recover_spin);
block_gen = ls->ls_recover_block;
start_gen = ls->ls_recover_start;
mount_gen = ls->ls_recover_mount;
if (lvb_gen < mount_gen) {
fs_info(sdp, "control_mount wait1 block %u start %u mount %u "
"lvb %u flags %lx\n", block_gen, start_gen, mount_gen,
lvb_gen, ls->ls_recover_flags);
spin_unlock(&ls->ls_recover_spin);
goto restart;
}
if (lvb_gen != start_gen) {
fs_info(sdp, "control_mount wait2 block %u start %u mount %u "
"lvb %u flags %lx\n", block_gen, start_gen, mount_gen,
lvb_gen, ls->ls_recover_flags);
spin_unlock(&ls->ls_recover_spin);
goto restart;
}
if (block_gen == start_gen) {
fs_info(sdp, "control_mount wait3 block %u start %u mount %u "
"lvb %u flags %lx\n", block_gen, start_gen, mount_gen,
lvb_gen, ls->ls_recover_flags);
spin_unlock(&ls->ls_recover_spin);
goto restart;
}
clear_bit(DFL_BLOCK_LOCKS, &ls->ls_recover_flags);
set_bit(DFL_MOUNT_DONE, &ls->ls_recover_flags);
memset(ls->ls_recover_submit, 0, ls->ls_recover_size*sizeof(uint32_t));
memset(ls->ls_recover_result, 0, ls->ls_recover_size*sizeof(uint32_t));
spin_unlock(&ls->ls_recover_spin);
return 0;
fail:
mounted_unlock(sdp);
control_unlock(sdp);
return error;
}