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authorNiklas Cassel <cassel@kernel.org>2026-09-16 15:00:32 +0200
committerNiklas Cassel <cassel@kernel.org>2026-09-16 16:18:00 +0200
commit8d836581f9b1f57ceaa2b47654754ef1260b410b (patch)
tree1dbd4d0dfb99c2e238356cbe947e5b0be3e3a571 /arch/powerpc/lib/locks.c
downloadlinux-stable-8d836581f9b1f57ceaa2b47654754ef1260b410b.tar.gz
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ata: libata-scsi: fix ata_dsm_trim_pages() kernel-docgrafted
make htmldocs fails with: Documentation/driver-api/libata:604: ./drivers/ata/libata-scsi.c:2301: ERROR: Unexpected indentation. [docutils] The Return: section of ata_dsm_trim_pages() ends its first sentence with a colon and continues with an indented bullet list. reStructuredText requires a blank line before an indented block, so docutils chokes on the list. Simply adding the missing blank line does not work either: Return: is a kernel-doc "special section", which is terminated by the first blank line, so the bullet list would end up in the Description section, detached from the sentence introducing it. Spell the two bounds out as prose instead, so that the Return: section stays self-contained. Documentation-only change. Fixes: e64e6b5dc867 ("ata: libata-scsi: scale DSM TRIM payload by MAX PAGES PER DSM COMMAND") Reported-by: Thomas Huth <thuth@redhat.com> Closes: https://lore.kernel.org/linux-ide/b0a0b8e8-cc4f-4c7b-8bc5-fee0712d405a@redhat.com/ Reviewed-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Thomas Huth <thuth@redhat.com> Link: https://lore.kernel.org/r/20260916130031.29990-2-cassel@kernel.org Signed-off-by: Niklas Cassel <cassel@kernel.org>
Diffstat (limited to 'arch/powerpc/lib/locks.c')
-rw-r--r--arch/powerpc/lib/locks.c65
1 files changed, 65 insertions, 0 deletions
diff --git a/arch/powerpc/lib/locks.c b/arch/powerpc/lib/locks.c
new file mode 100644
index 000000000..04165b7a1
--- /dev/null
+++ b/arch/powerpc/lib/locks.c
@@ -0,0 +1,65 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Spin and read/write lock operations.
+ *
+ * Copyright (C) 2001-2004 Paul Mackerras <paulus@au.ibm.com>, IBM
+ * Copyright (C) 2001 Anton Blanchard <anton@au.ibm.com>, IBM
+ * Copyright (C) 2002 Dave Engebretsen <engebret@us.ibm.com>, IBM
+ * Rework to support virtual processors
+ */
+
+#include <linux/kernel.h>
+#include <linux/spinlock.h>
+#include <linux/export.h>
+#include <linux/smp.h>
+
+/* waiting for a spinlock... */
+#if defined(CONFIG_PPC_SPLPAR)
+#include <asm/hvcall.h>
+#include <asm/smp.h>
+
+void splpar_spin_yield(arch_spinlock_t *lock)
+{
+ unsigned int lock_value, holder_cpu, yield_count;
+
+ lock_value = lock->slock;
+ if (lock_value == 0)
+ return;
+ holder_cpu = lock_value & 0xffff;
+ BUG_ON(holder_cpu >= NR_CPUS);
+
+ yield_count = yield_count_of(holder_cpu);
+ if ((yield_count & 1) == 0)
+ return; /* virtual cpu is currently running */
+ rmb();
+ if (lock->slock != lock_value)
+ return; /* something has changed */
+ yield_to_preempted(holder_cpu, yield_count);
+}
+EXPORT_SYMBOL_GPL(splpar_spin_yield);
+
+/*
+ * Waiting for a read lock or a write lock on a rwlock...
+ * This turns out to be the same for read and write locks, since
+ * we only know the holder if it is write-locked.
+ */
+void splpar_rw_yield(arch_rwlock_t *rw)
+{
+ int lock_value;
+ unsigned int holder_cpu, yield_count;
+
+ lock_value = rw->lock;
+ if (lock_value >= 0)
+ return; /* no write lock at present */
+ holder_cpu = lock_value & 0xffff;
+ BUG_ON(holder_cpu >= NR_CPUS);
+
+ yield_count = yield_count_of(holder_cpu);
+ if ((yield_count & 1) == 0)
+ return; /* virtual cpu is currently running */
+ rmb();
+ if (rw->lock != lock_value)
+ return; /* something has changed */
+ yield_to_preempted(holder_cpu, yield_count);
+}
+#endif