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Message-Id: <20200824103538.31446-4-john.ogness@linutronix.de>
Date: Mon, 24 Aug 2020 12:41:34 +0206
From: John Ogness <john.ogness@...utronix.de>
To: Petr Mladek <pmladek@...e.com>
Cc: Sergey Senozhatsky <sergey.senozhatsky.work@...il.com>,
Sergey Senozhatsky <sergey.senozhatsky@...il.com>,
Steven Rostedt <rostedt@...dmis.org>,
Linus Torvalds <torvalds@...ux-foundation.org>,
Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
Thomas Gleixner <tglx@...utronix.de>,
Peter Zijlstra <peterz@...radead.org>,
Andrea Parri <parri.andrea@...il.com>,
Paul McKenney <paulmck@...nel.org>, kexec@...ts.infradead.org,
linux-kernel@...r.kernel.org
Subject: [PATCH v2 3/7][next] printk: ringbuffer: relocate get_data()
Move the internal get_data() function as-is above prb_reserve() so
that a later change can make use of the static function.
Signed-off-by: John Ogness <john.ogness@...utronix.de>
---
kernel/printk/printk_ringbuffer.c | 116 +++++++++++++++---------------
1 file changed, 58 insertions(+), 58 deletions(-)
diff --git a/kernel/printk/printk_ringbuffer.c b/kernel/printk/printk_ringbuffer.c
index d339ff7647da..86af38c2cf77 100644
--- a/kernel/printk/printk_ringbuffer.c
+++ b/kernel/printk/printk_ringbuffer.c
@@ -1038,6 +1038,64 @@ static unsigned int space_used(struct prb_data_ring *data_ring,
DATA_SIZE(data_ring) - DATA_INDEX(data_ring, blk_lpos->begin));
}
+/*
+ * Given @blk_lpos, return a pointer to the writer data from the data block
+ * and calculate the size of the data part. A NULL pointer is returned if
+ * @blk_lpos specifies values that could never be legal.
+ *
+ * This function (used by readers) performs strict validation on the lpos
+ * values to possibly detect bugs in the writer code. A WARN_ON_ONCE() is
+ * triggered if an internal error is detected.
+ */
+static const char *get_data(struct prb_data_ring *data_ring,
+ struct prb_data_blk_lpos *blk_lpos,
+ unsigned int *data_size)
+{
+ struct prb_data_block *db;
+
+ /* Data-less data block description. */
+ if (LPOS_DATALESS(blk_lpos->begin) && LPOS_DATALESS(blk_lpos->next)) {
+ if (blk_lpos->begin == NO_LPOS && blk_lpos->next == NO_LPOS) {
+ *data_size = 0;
+ return "";
+ }
+ return NULL;
+ }
+
+ /* Regular data block: @begin less than @next and in same wrap. */
+ if (DATA_WRAPS(data_ring, blk_lpos->begin) == DATA_WRAPS(data_ring, blk_lpos->next) &&
+ blk_lpos->begin < blk_lpos->next) {
+ db = to_block(data_ring, blk_lpos->begin);
+ *data_size = blk_lpos->next - blk_lpos->begin;
+
+ /* Wrapping data block: @begin is one wrap behind @next. */
+ } else if (DATA_WRAPS(data_ring, blk_lpos->begin + DATA_SIZE(data_ring)) ==
+ DATA_WRAPS(data_ring, blk_lpos->next)) {
+ db = to_block(data_ring, 0);
+ *data_size = DATA_INDEX(data_ring, blk_lpos->next);
+
+ /* Illegal block description. */
+ } else {
+ WARN_ON_ONCE(1);
+ return NULL;
+ }
+
+ /* A valid data block will always be aligned to the ID size. */
+ if (WARN_ON_ONCE(blk_lpos->begin != ALIGN(blk_lpos->begin, sizeof(db->id))) ||
+ WARN_ON_ONCE(blk_lpos->next != ALIGN(blk_lpos->next, sizeof(db->id)))) {
+ return NULL;
+ }
+
+ /* A valid data block will always have at least an ID. */
+ if (WARN_ON_ONCE(*data_size < sizeof(db->id)))
+ return NULL;
+
+ /* Subtract block ID space from size to reflect data size. */
+ *data_size -= sizeof(db->id);
+
+ return &db->data[0];
+}
+
/**
* prb_reserve() - Reserve space in the ringbuffer.
*
@@ -1192,64 +1250,6 @@ void prb_commit(struct prb_reserved_entry *e)
local_irq_restore(e->irqflags);
}
-/*
- * Given @blk_lpos, return a pointer to the writer data from the data block
- * and calculate the size of the data part. A NULL pointer is returned if
- * @blk_lpos specifies values that could never be legal.
- *
- * This function (used by readers) performs strict validation on the lpos
- * values to possibly detect bugs in the writer code. A WARN_ON_ONCE() is
- * triggered if an internal error is detected.
- */
-static const char *get_data(struct prb_data_ring *data_ring,
- struct prb_data_blk_lpos *blk_lpos,
- unsigned int *data_size)
-{
- struct prb_data_block *db;
-
- /* Data-less data block description. */
- if (LPOS_DATALESS(blk_lpos->begin) && LPOS_DATALESS(blk_lpos->next)) {
- if (blk_lpos->begin == NO_LPOS && blk_lpos->next == NO_LPOS) {
- *data_size = 0;
- return "";
- }
- return NULL;
- }
-
- /* Regular data block: @begin less than @next and in same wrap. */
- if (DATA_WRAPS(data_ring, blk_lpos->begin) == DATA_WRAPS(data_ring, blk_lpos->next) &&
- blk_lpos->begin < blk_lpos->next) {
- db = to_block(data_ring, blk_lpos->begin);
- *data_size = blk_lpos->next - blk_lpos->begin;
-
- /* Wrapping data block: @begin is one wrap behind @next. */
- } else if (DATA_WRAPS(data_ring, blk_lpos->begin + DATA_SIZE(data_ring)) ==
- DATA_WRAPS(data_ring, blk_lpos->next)) {
- db = to_block(data_ring, 0);
- *data_size = DATA_INDEX(data_ring, blk_lpos->next);
-
- /* Illegal block description. */
- } else {
- WARN_ON_ONCE(1);
- return NULL;
- }
-
- /* A valid data block will always be aligned to the ID size. */
- if (WARN_ON_ONCE(blk_lpos->begin != ALIGN(blk_lpos->begin, sizeof(db->id))) ||
- WARN_ON_ONCE(blk_lpos->next != ALIGN(blk_lpos->next, sizeof(db->id)))) {
- return NULL;
- }
-
- /* A valid data block will always have at least an ID. */
- if (WARN_ON_ONCE(*data_size < sizeof(db->id)))
- return NULL;
-
- /* Subtract block ID space from size to reflect data size. */
- *data_size -= sizeof(db->id);
-
- return &db->data[0];
-}
-
/*
* Count the number of lines in provided text. All text has at least 1 line
* (even if @text_size is 0). Each '\n' processed is counted as an additional
--
2.20.1
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