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authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-23 13:28:57 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-23 13:28:57 -0700
commit4352b8aee98005853aa63f57d6377282de17a33f (patch)
tree27614d7a9ef05c32d089004e104364ce42324837 /tools/perf/util/strbuf.h
downloadlinux-stable-4352b8aee98005853aa63f57d6377282de17a33f.tar.gz
linux-stable-4352b8aee98005853aa63f57d6377282de17a33f.zip
Merge tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linuxgrafted
Pull I3C updates from Alexandre Belloni: "A new driver this cycle, for the AMD AXI I3C controller. There are also new features such as IBI wakeup support, SETAASA device discovery and ACPI support for the the DAA methods, meaning we can now communicate with the SPD devices on DDR5 modules. New driver: - AMD AXI I3C master controller Subsystem: - I3C Common Command Code (CCC) handling improvements, especially around GET CCCs - SETAASA device discovery support - ACPI support for all existing DAA methods like SETDASA, SETNEWDA as well as I2C devices on I3C bus - IBI-based wakeup support Drivers: - dw: SETAASA support - mipi-i3c-hci: advertise IBI wakeup capability, AMD_PT I3C controller support, PIO queue management support for HCI v1.2 - renesas: improve suspend to RAM support, add runtime PM support" * tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux: (70 commits) i3c: dw: reduce do_daa time if there's no client i3c: mipi-i3c-hci: Add support for AMD_PT I3C controller i3c: mipi-i3c-hci: Add PIO queue management support for HCI v1.2 i3c: mipi-i3c-hci: Fix missing STAT_IBI_STATUS_THLD in PIO mode i3c: dw: rename "pclk" to "apb" to match dt-binding i3c: dw: make struct dw_i3c_cmd smaller i3c: dw: use COMMAND_PORT_TRANSFER_ARG instead of hardcoding i3c: renesas: Don't register devices when ENTDAA times out i3c: master: dw-i3c-master: fix OD timing for first broadcast i3c: mipi-i3c-hci: Advertise IBI wakeup capability i3c: mipi-i3c-hci: Factor out i3c_hci_sysdev() i3c: mipi-i3c-hci-pci: Propagate I3C wakeup requirements to PCI i3c: master: Reject IBI requests from non-IBI-capable devices i3c: master: Add helper to query bus wakeup requirements i3c: master: Report wakeup events for IBIs i3c: master: Support IBI-based wakeup capability i3c: master: Fix potential UAF in i3c_device_match() i3c: master: Fix potential UAF in i3c_device_uevent() i3c: Make dev->desc locking assumptions explicit i3c: master: Fix use-after-free of master->this ...
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diff --git a/tools/perf/util/strbuf.h b/tools/perf/util/strbuf.h
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+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __PERF_STRBUF_H
+#define __PERF_STRBUF_H
+
+/*
+ * Strbuf's can be use in many ways: as a byte array, or to store arbitrary
+ * long, overflow safe strings.
+ *
+ * Strbufs has some invariants that are very important to keep in mind:
+ *
+ * 1. the ->buf member is always malloc-ed, hence strbuf's can be used to
+ * build complex strings/buffers whose final size isn't easily known.
+ *
+ * It is NOT legal to copy the ->buf pointer away.
+ * `strbuf_detach' is the operation that detaches a buffer from its shell
+ * while keeping the shell valid wrt its invariants.
+ *
+ * 2. the ->buf member is a byte array that has at least ->len + 1 bytes
+ * allocated. The extra byte is used to store a '\0', allowing the ->buf
+ * member to be a valid C-string. Every strbuf function ensure this
+ * invariant is preserved.
+ *
+ * Note that it is OK to "play" with the buffer directly if you work it
+ * that way:
+ *
+ * strbuf_grow(sb, SOME_SIZE);
+ * ... Here, the memory array starting at sb->buf, and of length
+ * ... strbuf_avail(sb) is all yours, and you are sure that
+ * ... strbuf_avail(sb) is at least SOME_SIZE.
+ * strbuf_setlen(sb, sb->len + SOME_OTHER_SIZE);
+ *
+ * Of course, SOME_OTHER_SIZE must be smaller or equal to strbuf_avail(sb).
+ *
+ * Doing so is safe, though if it has to be done in many places, adding the
+ * missing API to the strbuf module is the way to go.
+ *
+ * XXX: do _not_ assume that the area that is yours is of size ->alloc - 1
+ * even if it's true in the current implementation. Alloc is somehow a
+ * "private" member that should not be messed with.
+ */
+
+#include <assert.h>
+#include <stdarg.h>
+#include <stddef.h>
+#include <string.h>
+#include <linux/compiler.h>
+#include <sys/types.h>
+
+extern char strbuf_slopbuf[];
+struct strbuf {
+ size_t alloc;
+ size_t len;
+ char *buf;
+};
+
+#define STRBUF_INIT { 0, 0, strbuf_slopbuf }
+
+/*----- strbuf life cycle -----*/
+int strbuf_init(struct strbuf *buf, ssize_t hint);
+void strbuf_release(struct strbuf *buf);
+char *strbuf_detach(struct strbuf *buf, size_t *);
+
+/*----- strbuf size related -----*/
+static inline ssize_t strbuf_avail(const struct strbuf *sb) {
+ return sb->alloc ? sb->alloc - sb->len - 1 : 0;
+}
+
+int strbuf_grow(struct strbuf *buf, size_t);
+
+static inline int strbuf_setlen(struct strbuf *sb, size_t len) {
+ if (!sb->alloc) {
+ int ret = strbuf_grow(sb, 0);
+ if (ret)
+ return ret;
+ }
+ assert(len < sb->alloc);
+ sb->len = len;
+ sb->buf[len] = '\0';
+ return 0;
+}
+
+/*----- add data in your buffer -----*/
+int strbuf_addch(struct strbuf *sb, int c);
+
+int strbuf_add(struct strbuf *buf, const void *, size_t);
+static inline int strbuf_addstr(struct strbuf *sb, const char *s) {
+ return strbuf_add(sb, s, strlen(s));
+}
+
+int strbuf_addf(struct strbuf *sb, const char *fmt, ...) __printf(2, 3);
+
+/* XXX: if read fails, any partial read is undone */
+ssize_t strbuf_read(struct strbuf *, int fd, ssize_t hint);
+
+#endif /* __PERF_STRBUF_H */