summaryrefslogtreecommitdiff
path: root/lib
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2024-06-28 09:25:21 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2024-06-28 09:25:21 -0700
commitcd63a278acedc375603820abff11a5414af53769 (patch)
treeec81b94aae190924b675541cf8b5b2978384987e /lib
parentcd17613f464e15ad0ca83de7ca79ba72e4e72f75 (diff)
parent64cd7de998f393e73981e2aa4ee13e4e887f01ea (diff)
Merge tag 'bcachefs-2024-06-28' of https://evilpiepirate.org/git/bcachefs
Pull bcachefs fixes from Kent Overstreet: "Simple stuff: - NULL ptr/err ptr deref fixes - fix for getting wedged on shutdown after journal error - fix missing recalc_capacity() call, capacity now changes correctly after a device goes read only however: our capacity calculation still doesn't take into account when we have mixed ro/rw devices and the ro devices have data on them, that's going to be a more involved fix to separate accounting for "capacity used on ro devices" and "capacity used on rw devices" - boring syzbot stuff Slightly more involved: - discard, invalidate workers are now per device this has the effect of simplifying how we take device refs in these paths, and the device ref cleanup fixes a longstanding race between the device removal path and the discard path - fixes for how the debugfs code takes refs on btree_trans objects we have debugfs code that prints in use btree_trans objects. It uses closure_get() on trans->ref, which is mainly for the cycle detector, but the debugfs code was using it on a closure that may have hit 0, which is not allowed; for performance reasons we cannot avoid having not-in-use transactions on the global list. Introduce some new primitives to fix this and make the synchronization here a whole lot saner" * tag 'bcachefs-2024-06-28' of https://evilpiepirate.org/git/bcachefs: bcachefs: Fix kmalloc bug in __snapshot_t_mut bcachefs: Discard, invalidate workers are now per device bcachefs: Fix shift-out-of-bounds in bch2_blacklist_entries_gc bcachefs: slab-use-after-free Read in bch2_sb_errors_from_cpu bcachefs: Add missing bch2_journal_do_writes() call bcachefs: Fix null ptr deref in journal_pins_to_text() bcachefs: Add missing recalc_capacity() call bcachefs: Fix btree_trans list ordering bcachefs: Fix race between trans_put() and btree_transactions_read() closures: closure_get_not_zero(), closure_return_sync() bcachefs: Make btree_deadlock_to_text() clearer bcachefs: fix seqmutex_relock() bcachefs: Fix freeing of error pointers
Diffstat (limited to 'lib')
-rw-r--r--lib/closure.c52
1 files changed, 46 insertions, 6 deletions
diff --git a/lib/closure.c b/lib/closure.c
index 2e1ee9fdec08..c971216d9d77 100644
--- a/lib/closure.c
+++ b/lib/closure.c
@@ -13,7 +13,7 @@
#include <linux/seq_file.h>
#include <linux/sched/debug.h>
-static inline void closure_put_after_sub(struct closure *cl, int flags)
+static inline void closure_put_after_sub_checks(int flags)
{
int r = flags & CLOSURE_REMAINING_MASK;
@@ -22,12 +22,17 @@ static inline void closure_put_after_sub(struct closure *cl, int flags)
flags & CLOSURE_GUARD_MASK, (unsigned) __fls(r)))
r &= ~CLOSURE_GUARD_MASK;
- if (!r) {
- smp_acquire__after_ctrl_dep();
+ WARN(!r && (flags & ~CLOSURE_DESTRUCTOR),
+ "closure ref hit 0 with incorrect flags set: %x (%u)",
+ flags & ~CLOSURE_DESTRUCTOR, (unsigned) __fls(flags));
+}
+
+static inline void closure_put_after_sub(struct closure *cl, int flags)
+{
+ closure_put_after_sub_checks(flags);
- WARN(flags & ~CLOSURE_DESTRUCTOR,
- "closure ref hit 0 with incorrect flags set: %x (%u)",
- flags & ~CLOSURE_DESTRUCTOR, (unsigned) __fls(flags));
+ if (!(flags & CLOSURE_REMAINING_MASK)) {
+ smp_acquire__after_ctrl_dep();
cl->closure_get_happened = false;
@@ -145,6 +150,41 @@ void __sched __closure_sync(struct closure *cl)
}
EXPORT_SYMBOL(__closure_sync);
+/*
+ * closure_return_sync - finish running a closure, synchronously (i.e. waiting
+ * for outstanding get()s to finish) and returning once closure refcount is 0.
+ *
+ * Unlike closure_sync() this doesn't reinit the ref to 1; subsequent
+ * closure_get_not_zero() calls waill fail.
+ */
+void __sched closure_return_sync(struct closure *cl)
+{
+ struct closure_syncer s = { .task = current };
+
+ cl->s = &s;
+ set_closure_fn(cl, closure_sync_fn, NULL);
+
+ unsigned flags = atomic_sub_return_release(1 + CLOSURE_RUNNING - CLOSURE_DESTRUCTOR,
+ &cl->remaining);
+
+ closure_put_after_sub_checks(flags);
+
+ if (unlikely(flags & CLOSURE_REMAINING_MASK)) {
+ while (1) {
+ set_current_state(TASK_UNINTERRUPTIBLE);
+ if (s.done)
+ break;
+ schedule();
+ }
+
+ __set_current_state(TASK_RUNNING);
+ }
+
+ if (cl->parent)
+ closure_put(cl->parent);
+}
+EXPORT_SYMBOL(closure_return_sync);
+
int __sched __closure_sync_timeout(struct closure *cl, unsigned long timeout)
{
struct closure_syncer s = { .task = current };