drbd: Ensure that an epoch contains only requests of one kind

The assert in drbd_req.c:755 forces us to have only requests of
one kind in an epoch. The two kinds we distinguish here are:
local-only or mirrored.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
This commit is contained in:
Philipp Reisner 2011-01-17 20:27:30 +01:00
parent 2deb8336d0
commit 6a35c45f89
3 changed files with 28 additions and 26 deletions

View File

@ -1261,9 +1261,14 @@ __drbd_set_state(struct drbd_conf *mdev, union drbd_state ns,
if (os.conn < C_CONNECTED && ns.conn >= C_CONNECTED)
drbd_resume_al(mdev);
if (os.conn == C_AHEAD && ns.conn != C_AHEAD)
/* Start a new epoch in case we start to mirror write requests */
if (!drbd_should_do_remote(os) && drbd_should_do_remote(ns))
tl_forget(mdev);
/* Do not add local-only requests to an epoch with mirrored requests */
if (drbd_should_do_remote(os) && !drbd_should_do_remote(ns))
set_bit(CREATE_BARRIER, &mdev->flags);
ascw = kmalloc(sizeof(*ascw), GFP_ATOMIC);
if (ascw) {
ascw->os = os;

View File

@ -762,27 +762,6 @@ static int drbd_may_do_local_read(struct drbd_conf *mdev, sector_t sector, int s
return 0 == drbd_bm_count_bits(mdev, sbnr, ebnr);
}
static bool drbd_should_do_remote(struct drbd_conf *mdev)
{
union drbd_state s = mdev->state;
return s.pdsk == D_UP_TO_DATE ||
(s.pdsk >= D_INCONSISTENT &&
s.conn >= C_WF_BITMAP_T &&
s.conn < C_AHEAD);
/* Before proto 96 that was >= CONNECTED instead of >= C_WF_BITMAP_T.
That is equivalent since before 96 IO was frozen in the C_WF_BITMAP*
states. */
}
static bool drbd_should_send_oos(struct drbd_conf *mdev)
{
union drbd_state s = mdev->state;
return s.conn == C_AHEAD || s.conn == C_WF_BITMAP_S;
/* pdsk = D_INCONSISTENT as a consequence. Protocol 96 check not necessary
since we enter state C_AHEAD only if proto >= 96 */
}
static int drbd_make_request_common(struct drbd_conf *mdev, struct bio *bio, unsigned long start_time)
{
const int rw = bio_rw(bio);
@ -854,8 +833,8 @@ static int drbd_make_request_common(struct drbd_conf *mdev, struct bio *bio, uns
drbd_al_begin_io(mdev, sector);
}
remote = remote && drbd_should_do_remote(mdev);
send_oos = rw == WRITE && drbd_should_send_oos(mdev);
remote = remote && drbd_should_do_remote(mdev->state);
send_oos = rw == WRITE && drbd_should_send_oos(mdev->state);
D_ASSERT(!(remote && send_oos));
if (!(local || remote) && !is_susp(mdev->state)) {
@ -896,8 +875,8 @@ allocate_barrier:
}
if (remote || send_oos) {
remote = drbd_should_do_remote(mdev);
send_oos = rw == WRITE && drbd_should_send_oos(mdev);
remote = drbd_should_do_remote(mdev->state);
send_oos = rw == WRITE && drbd_should_send_oos(mdev->state);
D_ASSERT(!(remote && send_oos));
if (!(remote || send_oos))

View File

@ -360,4 +360,22 @@ static inline int req_mod(struct drbd_request *req,
return rv;
}
static inline bool drbd_should_do_remote(union drbd_state s)
{
return s.pdsk == D_UP_TO_DATE ||
(s.pdsk >= D_INCONSISTENT &&
s.conn >= C_WF_BITMAP_T &&
s.conn < C_AHEAD);
/* Before proto 96 that was >= CONNECTED instead of >= C_WF_BITMAP_T.
That is equivalent since before 96 IO was frozen in the C_WF_BITMAP*
states. */
}
static inline bool drbd_should_send_oos(union drbd_state s)
{
return s.conn == C_AHEAD || s.conn == C_WF_BITMAP_S;
/* pdsk = D_INCONSISTENT as a consequence. Protocol 96 check not necessary
since we enter state C_AHEAD only if proto >= 96 */
}
#endif