Rust support

---
 kernel/kallsyms.c  | 26 ++++++++++++++++++++++----
 scripts/kallsyms.c | 29 ++++++++++++++++++++++++++---
 2 files changed, 48 insertions(+), 7 deletions(-)

kernel/kallsyms.c +22 -4

index 3011bc33a5ba..80702273494a 100644
@@ -69,12 +69,20 @@ static unsigned int kallsyms_expand_symbol(unsigned int off,
 	data = &kallsyms_names[off];
 	len = *data;
 	data++;
+	off++;
+
+	/* If MSB is 1, it is a "big" symbol, so needs an additional byte. */
+	if ((len & 0x80) != 0) {
+		len = (len & 0x7F) | (*data << 7);
+		data++;
+		off++;
+	}
 
 	/*
 	 * Update the offset to return the offset for the next symbol on
 	 * the compressed stream.
 	 */
-	off += len + 1;
+	off += len;
 
 	/*
 	 * For every byte on the compressed symbol data, copy the table

@@ -127,7 +135,7 @@ static char kallsyms_get_symbol_type(unsigned int off)
 static unsigned int get_symbol_offset(unsigned long pos)
 {
 	const u8 *name;
-	int i;
+	int i, len;
 
 	/*
 	 * Use the closest marker we have. We have markers every 256 positions,

@@ -141,8 +149,18 @@ static unsigned int get_symbol_offset(unsigned long pos)
 	 * so we just need to add the len to the current pointer for every
 	 * symbol we wish to skip.
 	 */
-	for (i = 0; i < (pos & 0xFF); i++)
-		name = name + (*name) + 1;
+	for (i = 0; i < (pos & 0xFF); i++) {
+		len = *name;
+
+		/*
+		 * If MSB is 1, it is a "big" symbol, so we need to look into
+		 * the next byte (and skip it, too).
+		 */
+		if ((len & 0x80) != 0)
+			len = ((len & 0x7F) | (name[1] << 7)) + 1;
+
+		name = name + len + 1;
+	}
 
 	return name - kallsyms_names;
 }

scripts/kallsyms.c +26 -3

index 54ad86d13784..79b11bb7f07d 100644
@@ -470,12 +470,35 @@ static void write_src(void)
 		if ((i & 0xFF) == 0)
 			markers[i >> 8] = off;
 
-		printf("\t.byte 0x%02x", table[i]->len);
+		/* There cannot be any symbol of length zero. */
+		if (table[i]->len == 0) {
+			fprintf(stderr, "kallsyms failure: "
+				"unexpected zero symbol length\n");
+			exit(EXIT_FAILURE);
+		}
+
+		/* Only lengths that fit in up-to-two-byte ULEB128 are supported. */
+		if (table[i]->len > 0x3FFF) {
+			fprintf(stderr, "kallsyms failure: "
+				"unexpected huge symbol length\n");
+			exit(EXIT_FAILURE);
+		}
+
+		/* Encode length with ULEB128. */
+		if (table[i]->len <= 0x7F) {
+			/* Most symbols use a single byte for the length. */
+			printf("\t.byte 0x%02x", table[i]->len);
+			off += table[i]->len + 1;
+		} else {
+			/* "Big" symbols use two bytes. */
+			printf("\t.byte 0x%02x, 0x%02x",
+				(table[i]->len & 0x7F) | 0x80,
+				(table[i]->len >> 7) & 0x7F);
+			off += table[i]->len + 2;
+		}
 		for (k = 0; k < table[i]->len; k++)
 			printf(", 0x%02x", table[i]->sym[k]);
 		printf("\n");
-
-		off += table[i]->len + 1;
 	}
 	printf("\n");

Signature · 1 line

2.34.1

Miguel Ojeda

author maintainer

2022-01-17 05:34 UTC #2 lore raw

PATCH v3 2/19 kallsyms: increase maximum kernel symbol length to 512

Rust symbols can become quite long due to namespacing introduced by modules, types, traits, generics, etc. For instance, the following code:

    pub mod my_module {
        pub struct MyType;
        pub struct MyGenericType<T>(T);

        pub trait MyTrait {
            fn my_method() -> u32;
        }

        impl MyTrait for MyGenericType<MyType> {
            fn my_method() -> u32 {
                42
            }
        }
    }

generates a symbol of length 96 when using the upcoming v0 mangling scheme:

_RNvXNtCshGpAVYOtgW1_7example9my_moduleINtB2_13MyGenericTypeNtB2_6MyTypeENtB2_7MyTrait9my_method

At the moment, Rust symbols may reach up to 300 in length. Setting 512 as the maximum seems like a reasonable choice to keep some headroom.

Co-developed-by Alex Gaynor <[email protected]>

Signed-off-by Alex Gaynor <[email protected]>

Co-developed-by Wedson Almeida Filho <[email protected]>

Signed-off-by Wedson Almeida Filho <[email protected]>

Co-developed-by Gary Guo <[email protected]>

Signed-off-by Gary Guo <[email protected]>

Co-developed-by Boqun Feng <[email protected]>

Signed-off-by Boqun Feng <[email protected]>

---
 include/linux/kallsyms.h            | 2 +-
 kernel/livepatch/core.c             | 4 ++--
 scripts/kallsyms.c                  | 2 +-
 tools/include/linux/kallsyms.h      | 2 +-
 tools/lib/perf/include/perf/event.h | 2 +-
 tools/lib/symbol/kallsyms.h         | 2 +-
 6 files changed, 7 insertions(+), 7 deletions(-)

include/linux/kallsyms.h +1 -1

index 4176c7eca7b5..5fb17dd4b6fa 100644
@@ -15,7 +15,7 @@
 
 #include <asm/sections.h>
 
-#define KSYM_NAME_LEN 128
+#define KSYM_NAME_LEN 512
 #define KSYM_SYMBOL_LEN (sizeof("%s+%#lx/%#lx [%s %s]") + \
 			(KSYM_NAME_LEN - 1) + \
 			2*(BITS_PER_LONG*3/10) + (MODULE_NAME_LEN - 1) + \

kernel/livepatch/core.c +2 -2

index 335d988bd811..73874e5edfda 100644
@@ -213,7 +213,7 @@ static int klp_resolve_symbols(Elf64_Shdr *sechdrs, const char *strtab,
 	 * we use the smallest/strictest upper bound possible (56, based on
 	 * the current definition of MODULE_NAME_LEN) to prevent overflows.
 	 */
-	BUILD_BUG_ON(MODULE_NAME_LEN < 56 || KSYM_NAME_LEN != 128);
+	BUILD_BUG_ON(MODULE_NAME_LEN < 56 || KSYM_NAME_LEN != 512);
 
 	relas = (Elf_Rela *) relasec->sh_addr;
 	/* For each rela in this klp relocation section */

@@ -227,7 +227,7 @@ static int klp_resolve_symbols(Elf64_Shdr *sechdrs, const char *strtab,
 
 		/* Format: .klp.sym.sym_objname.sym_name,sympos */
 		cnt = sscanf(strtab + sym->st_name,
-			     ".klp.sym.%55[^.].%127[^,],%lu",
+			     ".klp.sym.%55[^.].%511[^,],%lu",
 			     sym_objname, sym_name, &sympos);
 		if (cnt != 3) {
 			pr_err("symbol %s has an incorrectly formatted name\n",

scripts/kallsyms.c +1 -1

index 79b11bb7f07d..72ba0fe4e43b 100644
@@ -27,7 +27,7 @@
 
 #define ARRAY_SIZE(arr) (sizeof(arr) / sizeof(arr[0]))
 
-#define KSYM_NAME_LEN		128
+#define KSYM_NAME_LEN		512
 
 struct sym_entry {
 	unsigned long long addr;

tools/include/linux/kallsyms.h +1 -1

index efb6c3f5f2a9..5a37ccbec54f 100644
@@ -6,7 +6,7 @@
 #include <stdio.h>
 #include <unistd.h>
 
-#define KSYM_NAME_LEN 128
+#define KSYM_NAME_LEN 512
 
 struct module;

tools/lib/perf/include/perf/event.h +1 -1

index 75ee385fb078..acc4fa065ec7 100644
@@ -95,7 +95,7 @@ struct perf_record_throttle {
 };
 
 #ifndef KSYM_NAME_LEN
-#define KSYM_NAME_LEN 256
+#define KSYM_NAME_LEN 512
 #endif
 
 struct perf_record_ksymbol {

tools/lib/symbol/kallsyms.h +1 -1

index 72ab9870454b..542f9b059c3b 100644
@@ -7,7 +7,7 @@
 #include <linux/types.h>
 
 #ifndef KSYM_NAME_LEN
-#define KSYM_NAME_LEN 256
+#define KSYM_NAME_LEN 512
 #endif
 
 static inline u8 kallsyms2elf_binding(char type)

Signature · 1 line

2.34.1

Miguel Ojeda

author maintainer

2022-01-17 05:34 UTC #3 lore raw

PATCH v3 3/19 kallsyms: use the correct buffer size for symbols

From: Boqun Feng <[email protected]>

The buffered name size should be larger than KSYM_NAME_LEN, otherwise we cannot tell whether the size of a symbol name is too long.

Signed-off-by Boqun Feng <[email protected]>

---
 scripts/kallsyms.c | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

scripts/kallsyms.c +6 -3

index 72ba0fe4e43b..0e37c19d84af 100644
@@ -27,6 +27,9 @@
 
 #define ARRAY_SIZE(arr) (sizeof(arr) / sizeof(arr[0]))
 
+#define _stringify_1(x)	#x
+#define _stringify(x)	_stringify_1(x)
+
 #define KSYM_NAME_LEN		512
 
 struct sym_entry {

@@ -197,15 +200,15 @@ static void check_symbol_range(const char *sym, unsigned long long addr,
 
 static struct sym_entry *read_symbol(FILE *in)
 {
-	char name[500], type;
+	char name[KSYM_NAME_LEN+1], type;
 	unsigned long long addr;
 	unsigned int len;
 	struct sym_entry *sym;
 	int rc;
 
-	rc = fscanf(in, "%llx %c %499s\n", &addr, &type, name);
+	rc = fscanf(in, "%llx %c %" _stringify(KSYM_NAME_LEN) "s\n", &addr, &type, name);
 	if (rc != 3) {
-		if (rc != EOF && fgets(name, 500, in) == NULL)
+		if (rc != EOF && fgets(name, KSYM_NAME_LEN + 1, in) == NULL)
 			fprintf(stderr, "Read error or end of file.\n");
 		return NULL;
 	}

Signature · 1 line

2.34.1

Miguel Ojeda

author maintainer

2022-01-17 05:34 UTC #4 lore raw

PATCH v3 4/19 rust: add C helpers

This source file contains forwarders to C macros and inlined functions.

Co-developed-by Alex Gaynor <[email protected]>

Signed-off-by Alex Gaynor <[email protected]>

Co-developed-by Geoffrey Thomas <[email protected]>

Signed-off-by Geoffrey Thomas <[email protected]>

Co-developed-by Wedson Almeida Filho <[email protected]>

Signed-off-by Wedson Almeida Filho <[email protected]>

Co-developed-by Sven Van Asbroeck <[email protected]>

Signed-off-by Sven Van Asbroeck <[email protected]>

Co-developed-by Gary Guo <[email protected]>

Signed-off-by Gary Guo <[email protected]>

Co-developed-by Boqun Feng <[email protected]>

Signed-off-by Boqun Feng <[email protected]>

Co-developed-by Maciej Falkowski <[email protected]>

Signed-off-by Maciej Falkowski <[email protected]>

---
 rust/helpers.c | 508 +++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 508 insertions(+)
 create mode 100644 rust/helpers.c

rust/helpers.c new file +508 -0

new file mode 100644
index 000000000000..324ed4dc27d5
@@ -0,0 +1,508 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/bug.h>
+#include <linux/build_bug.h>
+#include <linux/clk.h>
+#include <linux/uaccess.h>
+#include <linux/sched/signal.h>
+#include <linux/gfp.h>
+#include <linux/highmem.h>
+#include <linux/uio.h>
+#include <linux/errname.h>
+#include <linux/mutex.h>
+#include <linux/platform_device.h>
+#include <linux/security.h>
+#include <asm/io.h>
+#include <linux/irq.h>
+#include <linux/irqchip/chained_irq.h>
+#include <linux/irqdomain.h>
+#include <linux/amba/bus.h>
+#include <linux/of_device.h>
+
+__noreturn void rust_helper_BUG(void)
+{
+	BUG();
+}
+
+void rust_helper_clk_disable_unprepare(struct clk *clk)
+{
+	return clk_disable_unprepare(clk);
+}
+EXPORT_SYMBOL_GPL(rust_helper_clk_disable_unprepare);
+
+int rust_helper_clk_prepare_enable(struct clk *clk)
+{
+	return clk_prepare_enable(clk);
+}
+EXPORT_SYMBOL_GPL(rust_helper_clk_prepare_enable);
+
+unsigned long rust_helper_copy_from_user(void *to, const void __user *from, unsigned long n)
+{
+	return copy_from_user(to, from, n);
+}
+
+unsigned long rust_helper_copy_to_user(void __user *to, const void *from, unsigned long n)
+{
+	return copy_to_user(to, from, n);
+}
+
+unsigned long rust_helper_clear_user(void __user *to, unsigned long n)
+{
+	return clear_user(to, n);
+}
+
+void __iomem *rust_helper_ioremap(resource_size_t offset, unsigned long size)
+{
+	return ioremap(offset, size);
+}
+EXPORT_SYMBOL_GPL(rust_helper_ioremap);
+
+u8 rust_helper_readb(const volatile void __iomem *addr)
+{
+	return readb(addr);
+}
+EXPORT_SYMBOL_GPL(rust_helper_readb);
+
+u16 rust_helper_readw(const volatile void __iomem *addr)
+{
+	return readw(addr);
+}
+EXPORT_SYMBOL_GPL(rust_helper_readw);
+
+u32 rust_helper_readl(const volatile void __iomem *addr)
+{
+	return readl(addr);
+}
+EXPORT_SYMBOL_GPL(rust_helper_readl);
+
+#ifdef CONFIG_64BIT
+u64 rust_helper_readq(const volatile void __iomem *addr)
+{
+	return readq(addr);
+}
+EXPORT_SYMBOL_GPL(rust_helper_readq);
+#endif
+
+void rust_helper_writeb(u8 value, volatile void __iomem *addr)
+{
+	writeb(value, addr);
+}
+EXPORT_SYMBOL_GPL(rust_helper_writeb);
+
+void rust_helper_writew(u16 value, volatile void __iomem *addr)
+{
+	writew(value, addr);
+}
+EXPORT_SYMBOL_GPL(rust_helper_writew);
+
+void rust_helper_writel(u32 value, volatile void __iomem *addr)
+{
+	writel(value, addr);
+}
+EXPORT_SYMBOL_GPL(rust_helper_writel);
+
+#ifdef CONFIG_64BIT
+void rust_helper_writeq(u64 value, volatile void __iomem *addr)
+{
+	writeq(value, addr);
+}
+EXPORT_SYMBOL_GPL(rust_helper_writeq);
+#endif
+
+u8 rust_helper_readb_relaxed(const volatile void __iomem *addr)
+{
+	return readb_relaxed(addr);
+}
+EXPORT_SYMBOL_GPL(rust_helper_readb_relaxed);
+
+u16 rust_helper_readw_relaxed(const volatile void __iomem *addr)
+{
+	return readw_relaxed(addr);
+}
+EXPORT_SYMBOL_GPL(rust_helper_readw_relaxed);
+
+u32 rust_helper_readl_relaxed(const volatile void __iomem *addr)
+{
+	return readl_relaxed(addr);
+}
+EXPORT_SYMBOL_GPL(rust_helper_readl_relaxed);
+
+#ifdef CONFIG_64BIT
+u64 rust_helper_readq_relaxed(const volatile void __iomem *addr)
+{
+	return readq_relaxed(addr);
+}
+EXPORT_SYMBOL_GPL(rust_helper_readq_relaxed);
+#endif
+
+void rust_helper_writeb_relaxed(u8 value, volatile void __iomem *addr)
+{
+        writeb_relaxed(value, addr);
+}
+EXPORT_SYMBOL_GPL(rust_helper_writeb_relaxed);
+
+void rust_helper_writew_relaxed(u16 value, volatile void __iomem *addr)
+{
+        writew_relaxed(value, addr);
+}
+EXPORT_SYMBOL_GPL(rust_helper_writew_relaxed);
+
+void rust_helper_writel_relaxed(u32 value, volatile void __iomem *addr)
+{
+        writel_relaxed(value, addr);
+}
+EXPORT_SYMBOL_GPL(rust_helper_writel_relaxed);
+
+#ifdef CONFIG_64BIT
+void rust_helper_writeq_relaxed(u64 value, volatile void __iomem *addr)
+{
+        writeq_relaxed(value, addr);
+}
+EXPORT_SYMBOL_GPL(rust_helper_writeq_relaxed);
+#endif
+void rust_helper___spin_lock_init(spinlock_t *lock, const char *name,
+				  struct lock_class_key *key)
+{
+#ifdef CONFIG_DEBUG_SPINLOCK
+	__spin_lock_init(lock, name, key);
+#else
+	spin_lock_init(lock);
+#endif
+}
+EXPORT_SYMBOL_GPL(rust_helper___spin_lock_init);
+
+void rust_helper_spin_lock(spinlock_t *lock)
+{
+	spin_lock(lock);
+}
+EXPORT_SYMBOL_GPL(rust_helper_spin_lock);
+
+void rust_helper_spin_unlock(spinlock_t *lock)
+{
+	spin_unlock(lock);
+}
+EXPORT_SYMBOL_GPL(rust_helper_spin_unlock);
+
+unsigned long rust_helper_spin_lock_irqsave(spinlock_t *lock)
+{
+	unsigned long flags;
+	spin_lock_irqsave(lock, flags);
+	return flags;
+}
+EXPORT_SYMBOL_GPL(rust_helper_spin_lock_irqsave);
+
+void rust_helper_spin_unlock_irqrestore(spinlock_t *lock, unsigned long flags)
+{
+	spin_unlock_irqrestore(lock, flags);
+}
+EXPORT_SYMBOL_GPL(rust_helper_spin_unlock_irqrestore);
+
+void rust_helper_init_wait(struct wait_queue_entry *wq_entry)
+{
+	init_wait(wq_entry);
+}
+EXPORT_SYMBOL_GPL(rust_helper_init_wait);
+
+int rust_helper_signal_pending(struct task_struct *t)
+{
+	return signal_pending(t);
+}
+EXPORT_SYMBOL_GPL(rust_helper_signal_pending);
+
+struct page *rust_helper_alloc_pages(gfp_t gfp_mask, unsigned int order)
+{
+	return alloc_pages(gfp_mask, order);
+}
+EXPORT_SYMBOL_GPL(rust_helper_alloc_pages);
+
+void *rust_helper_kmap(struct page *page)
+{
+	return kmap(page);
+}
+EXPORT_SYMBOL_GPL(rust_helper_kmap);
+
+void rust_helper_kunmap(struct page *page)
+{
+	return kunmap(page);
+}
+EXPORT_SYMBOL_GPL(rust_helper_kunmap);
+
+int rust_helper_cond_resched(void)
+{
+	return cond_resched();
+}
+EXPORT_SYMBOL_GPL(rust_helper_cond_resched);
+
+size_t rust_helper_copy_from_iter(void *addr, size_t bytes, struct iov_iter *i)
+{
+	return copy_from_iter(addr, bytes, i);
+}
+EXPORT_SYMBOL_GPL(rust_helper_copy_from_iter);
+
+size_t rust_helper_copy_to_iter(const void *addr, size_t bytes, struct iov_iter *i)
+{
+	return copy_to_iter(addr, bytes, i);
+}
+EXPORT_SYMBOL_GPL(rust_helper_copy_to_iter);
+
+bool rust_helper_IS_ERR(__force const void *ptr)
+{
+	return IS_ERR(ptr);
+}
+EXPORT_SYMBOL_GPL(rust_helper_IS_ERR);
+
+long rust_helper_PTR_ERR(__force const void *ptr)
+{
+	return PTR_ERR(ptr);
+}
+EXPORT_SYMBOL_GPL(rust_helper_PTR_ERR);
+
+const char *rust_helper_errname(int err)
+{
+	return errname(err);
+}
+EXPORT_SYMBOL_GPL(rust_helper_errname);
+
+void rust_helper_mutex_lock(struct mutex *lock)
+{
+	mutex_lock(lock);
+}
+EXPORT_SYMBOL_GPL(rust_helper_mutex_lock);
+
+void rust_helper_amba_set_drvdata(struct amba_device *dev, void *data)
+{
+	amba_set_drvdata(dev, data);
+}
+EXPORT_SYMBOL_GPL(rust_helper_amba_set_drvdata);
+
+void *rust_helper_amba_get_drvdata(struct amba_device *dev)
+{
+	return amba_get_drvdata(dev);
+}
+EXPORT_SYMBOL_GPL(rust_helper_amba_get_drvdata);
+
+void *
+rust_helper_platform_get_drvdata(const struct platform_device *pdev)
+{
+	return platform_get_drvdata(pdev);
+}
+EXPORT_SYMBOL_GPL(rust_helper_platform_get_drvdata);
+
+void
+rust_helper_platform_set_drvdata(struct platform_device *pdev,
+				 void *data)
+{
+	return platform_set_drvdata(pdev, data);
+}
+EXPORT_SYMBOL_GPL(rust_helper_platform_set_drvdata);
+
+refcount_t rust_helper_REFCOUNT_INIT(int n)
+{
+	return (refcount_t)REFCOUNT_INIT(n);
+}
+EXPORT_SYMBOL_GPL(rust_helper_REFCOUNT_INIT);
+
+void rust_helper_refcount_inc(refcount_t *r)
+{
+	refcount_inc(r);
+}
+EXPORT_SYMBOL_GPL(rust_helper_refcount_inc);
+
+bool rust_helper_refcount_dec_and_test(refcount_t *r)
+{
+	return refcount_dec_and_test(r);
+}
+EXPORT_SYMBOL_GPL(rust_helper_refcount_dec_and_test);
+
+void rust_helper_rb_link_node(struct rb_node *node, struct rb_node *parent,
+			      struct rb_node **rb_link)
+{
+	rb_link_node(node, parent, rb_link);
+}
+EXPORT_SYMBOL_GPL(rust_helper_rb_link_node);
+
+struct task_struct *rust_helper_get_current(void)
+{
+	return current;
+}
+EXPORT_SYMBOL_GPL(rust_helper_get_current);
+
+void rust_helper_get_task_struct(struct task_struct * t)
+{
+	get_task_struct(t);
+}
+EXPORT_SYMBOL_GPL(rust_helper_get_task_struct);
+
+void rust_helper_put_task_struct(struct task_struct * t)
+{
+	put_task_struct(t);
+}
+EXPORT_SYMBOL_GPL(rust_helper_put_task_struct);
+
+int rust_helper_security_binder_set_context_mgr(const struct cred *mgr)
+{
+	return security_binder_set_context_mgr(mgr);
+}
+EXPORT_SYMBOL_GPL(rust_helper_security_binder_set_context_mgr);
+
+int rust_helper_security_binder_transaction(const struct cred *from,
+					    const struct cred *to)
+{
+	return security_binder_transaction(from, to);
+}
+EXPORT_SYMBOL_GPL(rust_helper_security_binder_transaction);
+
+int rust_helper_security_binder_transfer_binder(const struct cred *from,
+						const struct cred *to)
+{
+	return security_binder_transfer_binder(from, to);
+}
+EXPORT_SYMBOL_GPL(rust_helper_security_binder_transfer_binder);
+
+int rust_helper_security_binder_transfer_file(const struct cred *from,
+					      const struct cred *to,
+					      struct file *file)
+{
+	return security_binder_transfer_file(from, to, file);
+}
+EXPORT_SYMBOL_GPL(rust_helper_security_binder_transfer_file);
+
+void rust_helper_rcu_read_lock(void)
+{
+	rcu_read_lock();
+}
+EXPORT_SYMBOL_GPL(rust_helper_rcu_read_lock);
+
+void rust_helper_rcu_read_unlock(void)
+{
+	rcu_read_unlock();
+}
+EXPORT_SYMBOL_GPL(rust_helper_rcu_read_unlock);
+
+void rust_helper_synchronize_rcu(void)
+{
+	synchronize_rcu();
+}
+EXPORT_SYMBOL_GPL(rust_helper_synchronize_rcu);
+
+void *rust_helper_dev_get_drvdata(struct device *dev)
+{
+	return dev_get_drvdata(dev);
+}
+EXPORT_SYMBOL_GPL(rust_helper_dev_get_drvdata);
+
+const char *rust_helper_dev_name(const struct device *dev)
+{
+	return dev_name(dev);
+}
+EXPORT_SYMBOL_GPL(rust_helper_dev_name);
+
+void rust_helper___seqcount_init(seqcount_t *s, const char *name,
+				 struct lock_class_key *key)
+{
+	__seqcount_init(s, name, key);
+}
+EXPORT_SYMBOL_GPL(rust_helper___seqcount_init);
+
+unsigned rust_helper_read_seqcount_begin(seqcount_t *s)
+{
+	return read_seqcount_begin(s);
+}
+EXPORT_SYMBOL_GPL(rust_helper_read_seqcount_begin);
+
+int rust_helper_read_seqcount_retry(seqcount_t *s, unsigned start)
+{
+	return read_seqcount_retry(s, start);
+}
+EXPORT_SYMBOL_GPL(rust_helper_read_seqcount_retry);
+
+void rust_helper_write_seqcount_begin(seqcount_t *s)
+{
+	do_write_seqcount_begin(s);
+}
+EXPORT_SYMBOL_GPL(rust_helper_write_seqcount_begin);
+
+void rust_helper_write_seqcount_end(seqcount_t *s)
+{
+	do_write_seqcount_end(s);
+}
+EXPORT_SYMBOL_GPL(rust_helper_write_seqcount_end);
+
+void rust_helper_irq_set_handler_locked(struct irq_data *data,
+					irq_flow_handler_t handler)
+{
+	irq_set_handler_locked(data, handler);
+}
+EXPORT_SYMBOL_GPL(rust_helper_irq_set_handler_locked);
+
+void *rust_helper_irq_data_get_irq_chip_data(struct irq_data *d)
+{
+	return irq_data_get_irq_chip_data(d);
+}
+EXPORT_SYMBOL_GPL(rust_helper_irq_data_get_irq_chip_data);
+
+struct irq_chip *rust_helper_irq_desc_get_chip(struct irq_desc *desc)
+{
+	return irq_desc_get_chip(desc);
+}
+EXPORT_SYMBOL_GPL(rust_helper_irq_desc_get_chip);
+
+void *rust_helper_irq_desc_get_handler_data(struct irq_desc *desc)
+{
+	return irq_desc_get_handler_data(desc);
+}
+EXPORT_SYMBOL_GPL(rust_helper_irq_desc_get_handler_data);
+
+void rust_helper_chained_irq_enter(struct irq_chip *chip,
+				   struct irq_desc *desc)
+{
+	chained_irq_enter(chip, desc);
+}
+EXPORT_SYMBOL_GPL(rust_helper_chained_irq_enter);
+
+void rust_helper_chained_irq_exit(struct irq_chip *chip,
+				   struct irq_desc *desc)
+{
+	chained_irq_exit(chip, desc);
+}
+EXPORT_SYMBOL_GPL(rust_helper_chained_irq_exit);
+
+const struct cred *rust_helper_get_cred(const struct cred *cred)
+{
+	return get_cred(cred);
+}
+EXPORT_SYMBOL_GPL(rust_helper_get_cred);
+
+void rust_helper_put_cred(const struct cred *cred) {
+	put_cred(cred);
+}
+EXPORT_SYMBOL_GPL(rust_helper_put_cred);
+
+const struct of_device_id *rust_helper_of_match_device(
+		const struct of_device_id *matches, const struct device *dev)
+{
+	return of_match_device(matches, dev);
+}
+EXPORT_SYMBOL_GPL(rust_helper_of_match_device);
+
+/* We use bindgen's --size_t-is-usize option to bind the C size_t type
+ * as the Rust usize type, so we can use it in contexts where Rust
+ * expects a usize like slice (array) indices. usize is defined to be
+ * the same as C's uintptr_t type (can hold any pointer) but not
+ * necessarily the same as size_t (can hold the size of any single
+ * object). Most modern platforms use the same concrete integer type for
+ * both of them, but in case we find ourselves on a platform where
+ * that's not true, fail early instead of risking ABI or
+ * integer-overflow issues.
+ *
+ * If your platform fails this assertion, it means that you are in
+ * danger of integer-overflow bugs (even if you attempt to remove
+ * --size_t-is-usize). It may be easiest to change the kernel ABI on
+ * your platform such that size_t matches uintptr_t (i.e., to increase
+ * size_t, because uintptr_t has to be at least as big as size_t).
+*/
+static_assert(
+	sizeof(size_t) == sizeof(uintptr_t) &&
+	__alignof__(size_t) == __alignof__(uintptr_t),
+	"Rust code expects C size_t to match Rust usize"
+);

Signature · 1 line

2.34.1

Miguel Ojeda

author maintainer

2022-01-17 05:34 UTC #5 lore raw

PATCH v3 5/19 rust: add `compiler_builtins` crate

Rust provides compiler_builtins as a port of LLVM's compiler-rt. Since we do not need the vast majority of them, we avoid the dependency by providing our own crate.

Co-developed-by Alex Gaynor <[email protected]>

Signed-off-by Alex Gaynor <[email protected]>

Co-developed-by Wedson Almeida Filho <[email protected]>

Signed-off-by Wedson Almeida Filho <[email protected]>

Co-developed-by Sven Van Asbroeck <[email protected]>

Signed-off-by Sven Van Asbroeck <[email protected]>

Co-developed-by Gary Guo <[email protected]>

Signed-off-by Gary Guo <[email protected]>

---
 rust/compiler_builtins.rs | 57 +++++++++++++++++++++++++++++++++++++++
 1 file changed, 57 insertions(+)
 create mode 100644 rust/compiler_builtins.rs

rust/compiler_builtins.rs new file +57 -0

new file mode 100644
index 000000000000..a5a0be72591b
@@ -0,0 +1,57 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! Our own `compiler_builtins`.
+//!
+//! Rust provides [`compiler_builtins`] as a port of LLVM's [`compiler-rt`].
+//! Since we do not need the vast majority of them, we avoid the dependency
+//! by providing this file.
+//!
+//! At the moment, some builtins are required that should not be. For instance,
+//! [`core`] has floating-point functionality which we should not be compiling
+//! in. We will work with upstream [`core`] to provide feature flags to disable
+//! the parts we do not need. For the moment, we define them to [`panic!`] at
+//! runtime for simplicity to catch mistakes, instead of performing surgery
+//! on `core.o`.
+//!
+//! In any case, all these symbols are weakened to ensure we do not override
+//! those that may be provided by the rest of the kernel.
+//!
+//! [`compiler_builtins`]: https://github.com/rust-lang/compiler-builtins
+//! [`compiler-rt`]: https://compiler-rt.llvm.org/
+
+#![feature(compiler_builtins)]
+#![compiler_builtins]
+#![no_builtins]
+#![no_std]
+
+macro_rules! define_panicking_intrinsics(
+    ($reason: tt, { $($ident: ident, )* }) => {
+        $(
+            #[doc(hidden)]
+            #[no_mangle]
+            pub extern "C" fn $ident() {
+                panic!($reason);
+            }
+        )*
+    }
+);
+
+define_panicking_intrinsics!("`i128` should not be used", {
+    __ashrti3,
+    __muloti4,
+    __multi3,
+});
+
+define_panicking_intrinsics!("`u128` should not be used", {
+    __ashlti3,
+    __lshrti3,
+    __udivmodti4,
+    __udivti3,
+    __umodti3,
+});
+
+#[cfg(target_arch = "arm")]
+define_panicking_intrinsics!("`u64` division/modulo should not be used", {
+    __aeabi_uldivmod,
+    __mulodi4,
+});

Signature · 1 line

2.34.1

Miguel Ojeda

author maintainer

2022-01-17 05:34 UTC #6 lore raw

PATCH v3 6/19 rust: add `alloc` crate

This crate is a subset of the Rust standard library alloc, with some additions on top.

This is needed because upstream support for fallible allocations is a work in progress (i.e. the try_* versions of methods which return a Result instead of panicking).

Having the library in-tree also gives us a bit more freedom to experiment with new interfaces and allows us to iterate quickly.

Eventually, the goal is to have everything the kernel needs in upstream alloc and drop it from the kernel tree.

Co-developed-by Alex Gaynor <[email protected]>

Signed-off-by Alex Gaynor <[email protected]>

Co-developed-by Wedson Almeida Filho <[email protected]>

Signed-off-by Wedson Almeida Filho <[email protected]>

Co-developed-by Gary Guo <[email protected]>

Signed-off-by Gary Guo <[email protected]>

Co-developed-by Matthew Bakhtiari <[email protected]>

Signed-off-by Matthew Bakhtiari <[email protected]>

---
 rust/alloc/README.md              |   32 +
 rust/alloc/alloc.rs               |  427 ++++
 rust/alloc/borrow.rs              |  498 +++++
 rust/alloc/boxed.rs               | 1847 ++++++++++++++++
 rust/alloc/collections/mod.rs     |  156 ++
 rust/alloc/fmt.rs                 |  601 ++++++
 rust/alloc/lib.rs                 |  217 ++
 rust/alloc/macros.rs              |  126 ++
 rust/alloc/raw_vec.rs             |  549 +++++
 rust/alloc/slice.rs               | 1279 +++++++++++
 rust/alloc/str.rs                 |  624 ++++++
 rust/alloc/string.rs              | 2864 ++++++++++++++++++++++++
 rust/alloc/vec/drain.rs           |  159 ++
 rust/alloc/vec/drain_filter.rs    |  145 ++
 rust/alloc/vec/into_iter.rs       |  356 +++
 rust/alloc/vec/is_zero.rs         |  106 +
 rust/alloc/vec/mod.rs             | 3359 +++++++++++++++++++++++++++++
 rust/alloc/vec/partial_eq.rs      |   49 +
 rust/alloc/vec/set_len_on_drop.rs |   30 +
 rust/alloc/vec/spec_extend.rs     |  172 ++
 20 files changed, 13596 insertions(+)
 create mode 100644 rust/alloc/README.md
 create mode 100644 rust/alloc/alloc.rs
 create mode 100644 rust/alloc/borrow.rs
 create mode 100644 rust/alloc/boxed.rs
 create mode 100644 rust/alloc/collections/mod.rs
 create mode 100644 rust/alloc/fmt.rs
 create mode 100644 rust/alloc/lib.rs
 create mode 100644 rust/alloc/macros.rs
 create mode 100644 rust/alloc/raw_vec.rs
 create mode 100644 rust/alloc/slice.rs
 create mode 100644 rust/alloc/str.rs
 create mode 100644 rust/alloc/string.rs
 create mode 100644 rust/alloc/vec/drain.rs
 create mode 100644 rust/alloc/vec/drain_filter.rs
 create mode 100644 rust/alloc/vec/into_iter.rs
 create mode 100644 rust/alloc/vec/is_zero.rs
 create mode 100644 rust/alloc/vec/mod.rs
 create mode 100644 rust/alloc/vec/partial_eq.rs
 create mode 100644 rust/alloc/vec/set_len_on_drop.rs
 create mode 100644 rust/alloc/vec/spec_extend.rs

rust/alloc/README.md new file +32 -0

new file mode 100644
index 000000000000..a1bcc2cef0e6
@@ -0,0 +1,32 @@
+# `alloc`
+
+These source files come from the Rust standard library, hosted in
+the https://github.com/rust-lang/rust repository. For copyright
+details, see https://github.com/rust-lang/rust/blob/master/COPYRIGHT.
+
+Please note that these files should be kept as close as possible to
+upstream. In general, only additions should be performed (e.g. new
+methods). Eventually, changes should make it into upstream so that,
+at some point, this fork can be dropped from the kernel tree.
+
+
+## Rationale
+
+On one hand, kernel folks wanted to keep `alloc` in-tree to have more
+freedom in both workflow and actual features if actually needed
+(e.g. receiver types if we ended up using them), which is reasonable.
+
+On the other hand, Rust folks wanted to keep `alloc` as close as
+upstream as possible and avoid as much divergence as possible, which
+is also reasonable.
+
+We agreed on a middle-ground: we would keep a subset of `alloc`
+in-tree that would be as small and as close as possible to upstream.
+Then, upstream can start adding the functions that we add to `alloc`
+etc., until we reach a point where the kernel already knows exactly
+what it needs in `alloc` and all the new methods are merged into
+upstream, so that we can drop `alloc` from the kernel tree and go back
+to using the upstream one.
+
+By doing this, the kernel can go a bit faster now, and Rust can
+slowly incorporate and discuss the changes as needed.

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Signature · 1 line

2.34.1

Part of the diff is not shown here. View the raw message.

Miguel Ojeda

author maintainer

2022-01-17 05:34 UTC #7 lore raw

PATCH v3 7/19 rust: add `build_error` crate

From: Gary Guo <[email protected]>

The build_error crate provides the build_error function which is then used to provide the build_error! and the build_assert! macros.

build_assert! is intended to be used when static_assert! cannot be used, e.g. when the condition refers to generic parameters or parameters of an inline function.

Co-developed-by Alex Gaynor <[email protected]>

Signed-off-by Alex Gaynor <[email protected]>

Co-developed-by Wedson Almeida Filho <[email protected]>

Signed-off-by Wedson Almeida Filho <[email protected]>

Signed-off-by Gary Guo <[email protected]>

Co-developed-by Miguel Ojeda <[email protected]>

---
 rust/build_error.rs | 29 +++++++++++++++++++++++++++++
 1 file changed, 29 insertions(+)
 create mode 100644 rust/build_error.rs

rust/build_error.rs new file +29 -0

new file mode 100644
index 000000000000..34e589149d3e
@@ -0,0 +1,29 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! Build-time error.
+//!
+//! This crate provides a function `build_error`, which will panic in
+//! compile-time if executed in const context, and will cause a build error
+//! if not executed at compile time and the optimizer does not optimise away the
+//! call.
+//!
+//! It is used by `build_assert!` in the kernel crate, allowing checking of
+//! conditions that could be checked statically, but could not be enforced in
+//! Rust yet (e.g. perform some checks in const functions, but those
+//! functions could still be called in the runtime).
+
+#![no_std]
+
+/// Panics if executed in const context, or triggers a build error if not.
+#[inline(never)]
+#[cold]
+#[no_mangle]
+#[track_caller]
+pub const fn build_error(msg: &'static str) -> ! {
+    panic!("{}", msg);
+}
+
+#[cfg(CONFIG_RUST_BUILD_ASSERT_WARN)]
+#[link_section = ".gnu.warning.build_error"]
+#[used]
+static BUILD_ERROR_WARNING: [u8; 45] = *b"call to build_error present after compilation";

Signature · 1 line

2.34.1

Miguel Ojeda

author maintainer

2022-01-17 05:34 UTC #8 lore raw

PATCH v3 8/19 rust: add `macros` crate

This crate contains all the procedural macros ("proc macros") shared by all the kernel.

Procedural macros allow to create syntax extensions. They run at compile-time and can consume as well as produce Rust syntax.

For instance, the module! macro that is used by Rust modules is implemented here. It allows to easily declare the equivalent information to the MODULE_* macros in C modules, e.g.:

    module! {
        type: RustMinimal,
        name: b"rust_minimal",
        author: b"Rust for Linux Contributors",
        description: b"Rust minimal sample",
        license: b"GPL v2",
    }

Co-developed-by Alex Gaynor <[email protected]>

Signed-off-by Alex Gaynor <[email protected]>

Co-developed-by Finn Behrens <[email protected]>

Co-developed-by Adam Bratschi-Kaye <[email protected]>

Signed-off-by Adam Bratschi-Kaye <[email protected]>

Co-developed-by Wedson Almeida Filho <[email protected]>

Signed-off-by Wedson Almeida Filho <[email protected]>

Co-developed-by Sumera Priyadarsini <[email protected]>

Signed-off-by Sumera Priyadarsini <[email protected]>

Co-developed-by Gary Guo <[email protected]>

Signed-off-by Gary Guo <[email protected]>

Co-developed-by Matthew Bakhtiari <[email protected]>

Signed-off-by Matthew Bakhtiari <[email protected]>

---
 rust/macros/helpers.rs |  79 ++++++
 rust/macros/lib.rs     |  94 +++++++
 rust/macros/module.rs  | 622 +++++++++++++++++++++++++++++++++++++++++
 3 files changed, 795 insertions(+)
 create mode 100644 rust/macros/helpers.rs
 create mode 100644 rust/macros/lib.rs
 create mode 100644 rust/macros/module.rs

rust/macros/helpers.rs new file +79 -0

new file mode 100644
index 000000000000..ad210563e5a6
@@ -0,0 +1,79 @@
+// SPDX-License-Identifier: GPL-2.0
+
+use proc_macro::{token_stream, Group, TokenTree};
+
+pub(crate) fn try_ident(it: &mut token_stream::IntoIter) -> Option<String> {
+    if let Some(TokenTree::Ident(ident)) = it.next() {
+        Some(ident.to_string())
+    } else {
+        None
+    }
+}
+
+pub(crate) fn try_literal(it: &mut token_stream::IntoIter) -> Option<String> {
+    if let Some(TokenTree::Literal(literal)) = it.next() {
+        Some(literal.to_string())
+    } else {
+        None
+    }
+}
+
+pub(crate) fn try_byte_string(it: &mut token_stream::IntoIter) -> Option<String> {
+    try_literal(it).and_then(|byte_string| {
+        if byte_string.starts_with("b\"") && byte_string.ends_with('\"') {
+            Some(byte_string[2..byte_string.len() - 1].to_string())
+        } else {
+            None
+        }
+    })
+}
+
+pub(crate) fn expect_ident(it: &mut token_stream::IntoIter) -> String {
+    try_ident(it).expect("Expected Ident")
+}
+
+pub(crate) fn expect_punct(it: &mut token_stream::IntoIter) -> char {
+    if let TokenTree::Punct(punct) = it.next().expect("Reached end of token stream for Punct") {
+        punct.as_char()
+    } else {
+        panic!("Expected Punct");
+    }
+}
+
+pub(crate) fn expect_literal(it: &mut token_stream::IntoIter) -> String {
+    try_literal(it).expect("Expected Literal")
+}
+
+pub(crate) fn expect_group(it: &mut token_stream::IntoIter) -> Group {
+    if let TokenTree::Group(group) = it.next().expect("Reached end of token stream for Group") {
+        group
+    } else {
+        panic!("Expected Group");
+    }
+}
+
+pub(crate) fn expect_byte_string(it: &mut token_stream::IntoIter) -> String {
+    try_byte_string(it).expect("Expected byte string")
+}
+
+pub(crate) fn expect_end(it: &mut token_stream::IntoIter) {
+    if it.next().is_some() {
+        panic!("Expected end");
+    }
+}
+
+pub(crate) fn get_literal(it: &mut token_stream::IntoIter, expected_name: &str) -> String {
+    assert_eq!(expect_ident(it), expected_name);
+    assert_eq!(expect_punct(it), ':');
+    let literal = expect_literal(it);
+    assert_eq!(expect_punct(it), ',');
+    literal
+}
+
+pub(crate) fn get_byte_string(it: &mut token_stream::IntoIter, expected_name: &str) -> String {
+    assert_eq!(expect_ident(it), expected_name);
+    assert_eq!(expect_punct(it), ':');
+    let byte_string = expect_byte_string(it);
+    assert_eq!(expect_punct(it), ',');
+    byte_string
+}

rust/macros/lib.rs new file +94 -0

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rust/macros/module.rs new file +622 -0

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Signature · 1 line

2.34.1

Miguel Ojeda

author maintainer

2022-01-17 05:35 UTC #9 lore raw

PATCH v3 9/19 rust: add `kernel` crate

From: Wedson Almeida Filho <[email protected]>

The kernel crate currently includes all the abstractions that wrap kernel features written in C.

These abstractions call the C side of the kernel via the generated bindings with the bindgen tool. Modules developed in Rust should never call the bindings themselves.

In the future, as the abstractions grow in number, we may need to split this crate into several, possibly following a similar subdivision in subsystems as the kernel itself and/or moving the code to the actual subsystems.

Co-developed-by Alex Gaynor <[email protected]>

Signed-off-by Alex Gaynor <[email protected]>

Co-developed-by Geoffrey Thomas <[email protected]>

Signed-off-by Geoffrey Thomas <[email protected]>

Co-developed-by Finn Behrens <[email protected]>

Co-developed-by Adam Bratschi-Kaye <[email protected]>

Signed-off-by Adam Bratschi-Kaye <[email protected]>

Co-developed-by Michael Ellerman <[email protected]>

Signed-off-by Michael Ellerman <[email protected]>

Co-developed-by Sumera Priyadarsini <[email protected]>

Signed-off-by Sumera Priyadarsini <[email protected]>

Co-developed-by Sven Van Asbroeck <[email protected]>

Signed-off-by Sven Van Asbroeck <[email protected]>

Co-developed-by Gary Guo <[email protected]>

Signed-off-by Gary Guo <[email protected]>

Co-developed-by Boris-Chengbiao Zhou <[email protected]>

Signed-off-by Boris-Chengbiao Zhou <[email protected]>

Co-developed-by Boqun Feng <[email protected]>

Signed-off-by Boqun Feng <[email protected]>

Co-developed-by Fox Chen <[email protected]>

Signed-off-by Fox Chen <[email protected]>

Co-developed-by Dan Robertson <[email protected]>

Signed-off-by Dan Robertson <[email protected]>

Co-developed-by Viktor Garske <[email protected]>

Signed-off-by Viktor Garske <[email protected]>

Co-developed-by Dariusz Sosnowski <[email protected]>

Signed-off-by Dariusz Sosnowski <[email protected]>

Co-developed-by Léo Lanteri Thauvin <[email protected]>

Signed-off-by Léo Lanteri Thauvin <[email protected]>

Co-developed-by Niklas Mohrin <[email protected]>

Signed-off-by Niklas Mohrin <[email protected]>

Co-developed-by Gioh Kim <[email protected]>

Signed-off-by Gioh Kim <[email protected]>

Co-developed-by Daniel Xu <[email protected]>

Signed-off-by Daniel Xu <[email protected]>

Co-developed-by Milan Landaverde <[email protected]>

Signed-off-by Milan Landaverde <[email protected]>

Co-developed-by Morgan Bartlett <[email protected]>

Signed-off-by Morgan Bartlett <[email protected]>

Co-developed-by Hsiang-Cheng Yang <[email protected]>

Signed-off-by Hsiang-Cheng Yang <[email protected]>

Co-developed-by Maciej Falkowski <[email protected]>

Signed-off-by Maciej Falkowski <[email protected]>

Signed-off-by Wedson Almeida Filho <[email protected]>

Co-developed-by Miguel Ojeda <[email protected]>

---
 include/linux/spinlock.h            |  17 +-
 kernel/printk/printk.c              |   5 +-
 rust/kernel/allocator.rs            |  65 +++
 rust/kernel/amba.rs                 | 259 ++++++++++
 rust/kernel/bindings.rs             |  47 ++
 rust/kernel/bindings_helper.h       |  31 ++
 rust/kernel/buffer.rs               |  52 ++
 rust/kernel/build_assert.rs         |  80 +++
 rust/kernel/c_types.rs              | 119 +++++
 rust/kernel/chrdev.rs               | 209 ++++++++
 rust/kernel/clk.rs                  |  75 +++
 rust/kernel/cred.rs                 |  73 +++
 rust/kernel/device.rs               | 549 +++++++++++++++++++++
 rust/kernel/driver.rs               | 440 +++++++++++++++++
 rust/kernel/error.rs                | 542 +++++++++++++++++++++
 rust/kernel/file.rs                 | 147 ++++++
 rust/kernel/file_operations.rs      | 726 ++++++++++++++++++++++++++++
 rust/kernel/gpio.rs                 | 477 ++++++++++++++++++
 rust/kernel/io_buffer.rs            | 153 ++++++
 rust/kernel/io_mem.rs               | 227 +++++++++
 rust/kernel/iov_iter.rs             |  81 ++++
 rust/kernel/irq.rs                  | 409 ++++++++++++++++
 rust/kernel/lib.rs                  | 262 ++++++++++
 rust/kernel/linked_list.rs          | 247 ++++++++++
 rust/kernel/miscdev.rs              | 196 ++++++++
 rust/kernel/module_param.rs         | 497 +++++++++++++++++++
 rust/kernel/of.rs                   |  63 +++
 rust/kernel/pages.rs                | 162 +++++++
 rust/kernel/platform.rs             | 224 +++++++++
 rust/kernel/power.rs                | 118 +++++
 rust/kernel/prelude.rs              |  36 ++
 rust/kernel/print.rs                | 441 +++++++++++++++++
 rust/kernel/random.rs               |  50 ++
 rust/kernel/raw_list.rs             | 361 ++++++++++++++
 rust/kernel/rbtree.rs               | 562 +++++++++++++++++++++
 rust/kernel/revocable.rs            | 163 +++++++
 rust/kernel/security.rs             |  36 ++
 rust/kernel/static_assert.rs        |  39 ++
 rust/kernel/std_vendor.rs           | 150 ++++++
 rust/kernel/str.rs                  | 375 ++++++++++++++
 rust/kernel/sync/arc.rs             | 500 +++++++++++++++++++
 rust/kernel/sync/condvar.rs         | 138 ++++++
 rust/kernel/sync/guard.rs           | 181 +++++++
 rust/kernel/sync/locked_by.rs       | 112 +++++
 rust/kernel/sync/mod.rs             |  92 ++++
 rust/kernel/sync/mutex.rs           | 112 +++++
 rust/kernel/sync/revocable_mutex.rs | 184 +++++++
 rust/kernel/sync/seqlock.rs         | 202 ++++++++
 rust/kernel/sync/spinlock.rs        | 180 +++++++
 rust/kernel/sysctl.rs               | 197 ++++++++
 rust/kernel/task.rs                 | 182 +++++++
 rust/kernel/types.rs                | 486 +++++++++++++++++++
 rust/kernel/user_ptr.rs             | 175 +++++++
 53 files changed, 11499 insertions(+), 7 deletions(-)
 create mode 100644 rust/kernel/allocator.rs
 create mode 100644 rust/kernel/amba.rs
 create mode 100644 rust/kernel/bindings.rs
 create mode 100644 rust/kernel/bindings_helper.h
 create mode 100644 rust/kernel/buffer.rs
 create mode 100644 rust/kernel/build_assert.rs
 create mode 100644 rust/kernel/c_types.rs
 create mode 100644 rust/kernel/chrdev.rs
 create mode 100644 rust/kernel/clk.rs
 create mode 100644 rust/kernel/cred.rs
 create mode 100644 rust/kernel/device.rs
 create mode 100644 rust/kernel/driver.rs
 create mode 100644 rust/kernel/error.rs
 create mode 100644 rust/kernel/file.rs
 create mode 100644 rust/kernel/file_operations.rs
 create mode 100644 rust/kernel/gpio.rs
 create mode 100644 rust/kernel/io_buffer.rs
 create mode 100644 rust/kernel/io_mem.rs
 create mode 100644 rust/kernel/iov_iter.rs
 create mode 100644 rust/kernel/irq.rs
 create mode 100644 rust/kernel/lib.rs
 create mode 100644 rust/kernel/linked_list.rs
 create mode 100644 rust/kernel/miscdev.rs
 create mode 100644 rust/kernel/module_param.rs
 create mode 100644 rust/kernel/of.rs
 create mode 100644 rust/kernel/pages.rs
 create mode 100644 rust/kernel/platform.rs
 create mode 100644 rust/kernel/power.rs
 create mode 100644 rust/kernel/prelude.rs
 create mode 100644 rust/kernel/print.rs
 create mode 100644 rust/kernel/random.rs
 create mode 100644 rust/kernel/raw_list.rs
 create mode 100644 rust/kernel/rbtree.rs
 create mode 100644 rust/kernel/revocable.rs
 create mode 100644 rust/kernel/security.rs
 create mode 100644 rust/kernel/static_assert.rs
 create mode 100644 rust/kernel/std_vendor.rs
 create mode 100644 rust/kernel/str.rs
 create mode 100644 rust/kernel/sync/arc.rs
 create mode 100644 rust/kernel/sync/condvar.rs
 create mode 100644 rust/kernel/sync/guard.rs
 create mode 100644 rust/kernel/sync/locked_by.rs
 create mode 100644 rust/kernel/sync/mod.rs
 create mode 100644 rust/kernel/sync/mutex.rs
 create mode 100644 rust/kernel/sync/revocable_mutex.rs
 create mode 100644 rust/kernel/sync/seqlock.rs
 create mode 100644 rust/kernel/sync/spinlock.rs
 create mode 100644 rust/kernel/sysctl.rs
 create mode 100644 rust/kernel/task.rs
 create mode 100644 rust/kernel/types.rs
 create mode 100644 rust/kernel/user_ptr.rs

include/linux/spinlock.h +11 -6

index b4e5ca23f840..40e467cdee2d 100644
@@ -326,12 +326,17 @@ static __always_inline raw_spinlock_t *spinlock_check(spinlock_t *lock)
 
 #ifdef CONFIG_DEBUG_SPINLOCK
 
-# define spin_lock_init(lock)					\
-do {								\
-	static struct lock_class_key __key;			\
-								\
-	__raw_spin_lock_init(spinlock_check(lock),		\
-			     #lock, &__key, LD_WAIT_CONFIG);	\
+static inline void __spin_lock_init(spinlock_t *lock, const char *name,
+				    struct lock_class_key *key)
+{
+	__raw_spin_lock_init(spinlock_check(lock), name, key, LD_WAIT_CONFIG);
+}
+
+# define spin_lock_init(lock)			\
+do {						\
+	static struct lock_class_key __key;	\
+						\
+	__spin_lock_init(lock, #lock, &__key);	\
 } while (0)
 
 #else

kernel/printk/printk.c +4 -1

index 57b132b658e1..cbc35d586afb 100644
@@ -392,7 +392,10 @@ static struct latched_seq clear_seq = {
 /* the maximum size of a formatted record (i.e. with prefix added per line) */
 #define CONSOLE_LOG_MAX		1024
 
-/* the maximum size allowed to be reserved for a record */
+/*
+ * The maximum size allowed to be reserved for a record.
+ * Keep in sync with rust/kernel/print.rs.
+ */
 #define LOG_LINE_MAX		(CONSOLE_LOG_MAX - PREFIX_MAX)
 
 #define LOG_LEVEL(v)		((v) & 0x07)

rust/kernel/allocator.rs new file +65 -0

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rust/kernel/amba.rs new file +259 -0

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rust/kernel/bindings.rs new file +47 -0

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rust/kernel/bindings_helper.h new file +31 -0

new file mode 100644
index 000000000000..99a7d785ae01
@@ -0,0 +1,31 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#include <linux/cdev.h>
+#include <linux/clk.h>
+#include <linux/errname.h>
+#include <linux/fs.h>
+#include <linux/module.h>
+#include <linux/random.h>
+#include <linux/slab.h>
+#include <linux/sysctl.h>
+#include <linux/uaccess.h>
+#include <linux/uio.h>
+#include <linux/version.h>
+#include <linux/miscdevice.h>
+#include <linux/poll.h>
+#include <linux/mm.h>
+#include <linux/file.h>
+#include <uapi/linux/android/binder.h>
+#include <linux/platform_device.h>
+#include <linux/of_platform.h>
+#include <linux/security.h>
+#include <asm/io.h>
+#include <linux/irq.h>
+#include <linux/interrupt.h>
+#include <linux/irqdomain.h>
+#include <linux/amba/bus.h>
+#include <linux/gpio/driver.h>
+
+// `bindgen` gets confused at certain things
+const gfp_t BINDINGS_GFP_KERNEL = GFP_KERNEL;
+const gfp_t BINDINGS___GFP_ZERO = __GFP_ZERO;

rust/kernel/buffer.rs new file +52 -0

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rust/kernel/chrdev.rs new file +209 -0

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rust/kernel/clk.rs new file +75 -0

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rust/kernel/cred.rs new file +73 -0

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rust/kernel/driver.rs new file +440 -0

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rust/kernel/error.rs new file +542 -0

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rust/kernel/print.rs new file +441 -0

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rust/kernel/rbtree.rs new file +562 -0

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rust/kernel/revocable.rs new file +163 -0

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rust/kernel/security.rs new file +36 -0

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rust/kernel/static_assert.rs new file +39 -0

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Signature · 1 line

2.34.1

Part of the diff is not shown here. View the raw message.

Miguel Ojeda

author maintainer

2022-01-17 05:34 UTC #10 lore raw

PATCH v3 10/19 rust: export generated symbols

All symbols are reexported reusing the EXPORT_SYMBOL_GPL macro from C. The lists of symbols are generated on the fly.

There are three main sets of symbols to distinguish:

- The ones from the core and alloc crates (from the Rust standard library). The code is licensed as Apache/MIT.

- The ones from our abstractions in the kernel crate.

- The helpers (already exported since they are not generated).

We export everything as GPL. This ensures we do not mistakenly expose GPL kernel symbols/features as non-GPL, even indirectly.

Co-developed-by Alex Gaynor <[email protected]>

Signed-off-by Alex Gaynor <[email protected]>

Co-developed-by Wedson Almeida Filho <[email protected]>

Signed-off-by Wedson Almeida Filho <[email protected]>

---
 rust/exports.c | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)
 create mode 100644 rust/exports.c

rust/exports.c new file +16 -0

new file mode 100644
index 000000000000..d7dff1b3b919
@@ -0,0 +1,16 @@
+// SPDX-License-Identifier: GPL-2.0
+//
+// A hack to export Rust symbols for loadable modules without having to redo
+// the entire `include/linux/export.h` logic in Rust.
+//
+// This requires the Rust's new/future `v0` mangling scheme because the default
+// one ("legacy") uses invalid characters for C identifiers (thus we cannot use
+// the `EXPORT_SYMBOL_*` macros).
+
+#include <linux/module.h>
+
+#define EXPORT_SYMBOL_RUST_GPL(sym) extern int sym; EXPORT_SYMBOL_GPL(sym);
+
+#include "exports_core_generated.h"
+#include "exports_alloc_generated.h"
+#include "exports_kernel_generated.h"

Signature · 1 line

2.34.1

Miguel Ojeda

author maintainer

2022-01-17 05:35 UTC #11 lore raw

PATCH v3 11/19 vsprintf: add new `%pA` format specifier

From: Gary Guo <[email protected]>

This patch adds a format specifier %pA to vsprintf which formats a pointer as core::fmt::Arguments. Doing so allows us to directly format to the internal buffer of printf, so we do not have to use a temporary buffer on the stack to pre-assemble the message on the Rust side.

This specifier is intended only to be used from Rust and not for C, so checkpatch.pl is intentionally unchanged to catch any misuse.

Co-developed-by Alex Gaynor <[email protected]>

Signed-off-by Alex Gaynor <[email protected]>

Co-developed-by Wedson Almeida Filho <[email protected]>

Signed-off-by Wedson Almeida Filho <[email protected]>

Signed-off-by Gary Guo <[email protected]>

Co-developed-by Miguel Ojeda <[email protected]>

---
 lib/rust.h     | 14 ++++++++++++++
 lib/vsprintf.c |  7 +++++++
 2 files changed, 21 insertions(+)
 create mode 100644 lib/rust.h

lib/rust.h new file +14 -0

new file mode 100644
index 000000000000..9cf0b102b496
@@ -0,0 +1,14 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _LIB_RUST_H
+#define _LIB_RUST_H
+
+#ifdef CONFIG_RUST
+char *rust_fmt_argument(char* buf, char* end, void *ptr);
+#else
+static inline char *rust_fmt_argument(char* buf, char* end, void *ptr)
+{
+	return NULL;
+}
+#endif
+
+#endif /* _LIB_RUST_H */

lib/vsprintf.c +7 -0

index 58d5e567f836..84a1c9496e6e 100644
@@ -52,6 +52,7 @@
 
 #include <linux/string_helpers.h>
 #include "kstrtox.h"
+#include "rust.h"
 
 static noinline unsigned long long simple_strntoull(const char *startp, size_t max_chars, char **endp, unsigned int base)
 {

@@ -2388,6 +2389,10 @@ early_param("no_hash_pointers", no_hash_pointers_enable);
  *
  * Note: The default behaviour (unadorned %p) is to hash the address,
  * rendering it useful as a unique identifier.
+ *
+ * There is also a '%pA' format specifier, but it is only intended to be used
+ * from Rust code to format core::fmt::Arguments. Do *not* use it from C.
+ * See rust/kernel/print.rs for details.
  */
 static noinline_for_stack
 char *pointer(const char *fmt, char *buf, char *end, void *ptr,

@@ -2460,6 +2465,8 @@ char *pointer(const char *fmt, char *buf, char *end, void *ptr,
 		return device_node_string(buf, end, ptr, spec, fmt + 1);
 	case 'f':
 		return fwnode_string(buf, end, ptr, spec, fmt + 1);
+	case 'A':
+		return rust_fmt_argument(buf, end, ptr);
 	case 'x':
 		return pointer_string(buf, end, ptr, spec);
 	case 'e':

Signature · 1 line

2.34.1

Miguel Ojeda

author maintainer

2022-01-17 05:35 UTC #12 lore raw

PATCH v3 12/19 scripts: add `generate_rust_analyzer.py`

The generate_rust_analyzer.py script generates the configuration file (rust-project.json) for rust-analyzer.

rust-analyzer is a modular compiler frontend for the Rust language. It provides an LSP server which can be used in editors such as VS Code, Emacs or Vim.

Co-developed-by Alex Gaynor <[email protected]>

Signed-off-by Alex Gaynor <[email protected]>

Co-developed-by Finn Behrens <[email protected]>

Co-developed-by Wedson Almeida Filho <[email protected]>

Signed-off-by Wedson Almeida Filho <[email protected]>

Co-developed-by Gary Guo <[email protected]>

Signed-off-by Gary Guo <[email protected]>

Co-developed-by Boris-Chengbiao Zhou <[email protected]>

Signed-off-by Boris-Chengbiao Zhou <[email protected]>

---
 scripts/generate_rust_analyzer.py | 133 ++++++++++++++++++++++++++++++
 1 file changed, 133 insertions(+)
 create mode 100755 scripts/generate_rust_analyzer.py

scripts/generate_rust_analyzer.py new file +133 -0

new file mode 100755
index 000000000000..024f8b884c1b
@@ -0,0 +1,133 @@
+#!/usr/bin/env python3
+"""generate_rust_analyzer - Generates the `rust-project.json` file for `rust-analyzer`.
+"""
+
+import argparse
+import json
+import logging
+import pathlib
+import sys
+
+def generate_crates(srctree, objtree, sysroot_src):
+    # Generate the configuration list.
+    cfg = []
+    with open(objtree / "include" / "generated" / "rustc_cfg") as fd:
+        for line in fd:
+            line = line.replace("--cfg=", "")
+            line = line.replace("\n", "")
+            cfg.append(line)
+
+    # Now fill the crates list -- dependencies need to come first.
+    #
+    # Avoid O(n^2) iterations by keeping a map of indexes.
+    crates = []
+    crates_indexes = {}
+
+    def append_crate(display_name, root_module, deps, cfg=[], is_workspace_member=True, is_proc_macro=False):
+        crates_indexes[display_name] = len(crates)
+        crates.append({
+            "display_name": display_name,
+            "root_module": str(root_module),
+            "is_workspace_member": is_workspace_member,
+            "is_proc_macro": is_proc_macro,
+            "deps": [{"crate": crates_indexes[dep], "name": dep} for dep in deps],
+            "cfg": cfg,
+            "edition": "2021",
+            "env": {
+                "RUST_MODFILE": "This is only for rust-analyzer"
+            }
+        })
+
+    # First, the ones in `rust/` since they are a bit special.
+    append_crate(
+        "core",
+        sysroot_src / "core" / "src" / "lib.rs",
+        [],
+        is_workspace_member=False,
+    )
+
+    append_crate(
+        "compiler_builtins",
+        srctree / "rust" / "compiler_builtins.rs",
+        [],
+    )
+
+    append_crate(
+        "alloc",
+        srctree / "rust" / "alloc" / "lib.rs",
+        ["core", "compiler_builtins"],
+    )
+
+    append_crate(
+        "macros",
+        srctree / "rust" / "macros" / "lib.rs",
+        [],
+        is_proc_macro=True,
+    )
+    crates[-1]["proc_macro_dylib_path"] = "rust/libmacros.so"
+
+    append_crate(
+        "build_error",
+        srctree / "rust" / "build_error.rs",
+        ["core", "compiler_builtins"],
+    )
+
+    append_crate(
+        "kernel",
+        srctree / "rust" / "kernel" / "lib.rs",
+        ["core", "alloc", "macros", "build_error"],
+        cfg=cfg,
+    )
+    crates[-1]["env"]["OBJTREE"] = str(objtree.resolve(True))
+    crates[-1]["source"] = {
+        "include_dirs": [
+            str(srctree / "rust" / "kernel"),
+            str(objtree / "rust")
+        ],
+        "exclude_dirs": [],
+    }
+
+    # Then, the rest outside of `rust/`.
+    #
+    # We explicitly mention the top-level folders we want to cover.
+    for folder in ("samples", "drivers"):
+        for path in (srctree / folder).rglob("*.rs"):
+            logging.info("Checking %s", path)
+            name = path.name.replace(".rs", "")
+
+            # Skip those that are not crate roots.
+            if f"{name}.o" not in open(path.parent / "Makefile").read():
+                continue
+
+            logging.info("Adding %s", name)
+            append_crate(
+                name,
+                path,
+                ["core", "alloc", "kernel"],
+                cfg=cfg,
+            )
+
+    return crates
+
+def main():
+    parser = argparse.ArgumentParser()
+    parser.add_argument('--verbose', '-v', action='store_true')
+    parser.add_argument("srctree", type=pathlib.Path)
+    parser.add_argument("objtree", type=pathlib.Path)
+    parser.add_argument("sysroot_src", type=pathlib.Path)
+    args = parser.parse_args()
+
+    logging.basicConfig(
+        format="[%(asctime)s] [%(levelname)s] %(message)s",
+        level=logging.INFO if args.verbose else logging.WARNING
+    )
+
+    rust_project = {
+        "crates": generate_crates(args.srctree, args.objtree, args.sysroot_src),
+        "sysroot_src": str(args.sysroot_src),
+    }
+
+    json.dump(rust_project, sys.stdout, sort_keys=True, indent=4)
+
+if __name__ == "__main__":
+    main()

Signature · 1 line

2.34.1

Miguel Ojeda

author maintainer

2022-01-17 05:35 UTC #13 lore raw

PATCH v3 13/19 scripts: decode_stacktrace: demangle Rust symbols

Recent versions of both Binutils (c++filt) and LLVM (llvm-cxxfilt) provide Rust v0 mangling support.

Co-developed-by Alex Gaynor <[email protected]>

Signed-off-by Alex Gaynor <[email protected]>

Co-developed-by Wedson Almeida Filho <[email protected]>

Signed-off-by Wedson Almeida Filho <[email protected]>

---
I would like to use this patch for discussing the demangling topic.

The following discusses the different approaches we could take.

# Leave demangling to userspace

This is the easiest and less invasive approach, the one implemented by this patch.

The decode_stacktrace.sh script is already needed to map the offsets to the source code. Therefore, we could also take the chance to demangle the symbols here.

With this approach, we do not need to introduce any change in the vsprintf machinery and we minimize the risk of breaking user tools.

Note that, if we take this approach, it is likely we want to ask for a minimum version of either of the tools (since there may be users of the script that do not have recent enough toolchains).

# Demangling in kernelspace on-the-fly

That is, at backtrace print time, we demangle the Rust symbols.

The size of the code that would be needed is fairly small; around 5 KiB using the "official" library (written in Rust), e.g.:

    text    data    bss     dec      hex    filename
    7799976 1689820 2129920 11619716 b14d84 vmlinux
    7801111 1693916 2129920 11624947 b161f3 vmlinux + demangling

We can remove a few bits from the official library, e.g. punycode support that we do not need (all our identifiers will be ASCII), but it does not make a substantial difference.

The official library performs the demangling without requiring allocations. However, of course, it will increased our stack usage and complexity, specially considering a stack dump may be requested in not ideal conditions.

Furthermore, this approach (and the ones below) likely require adding a new %p specifier (or a new modifier to existing ones) if we do not want to affect non-backtrace uses of the B/S ones. Also, it is unclear whether we should write the demangled versions in an extra, different line or replace the real symbol -- we could be breaking user tools relying on parsing backtraces (e.g. our own decode_stacktrace.sh). For instance, they could be relying on having real symbols there, or may break due to e.g. spaces.

# Demangling at compile-time

This implies having kallsyms demangle all the Rust symbols.

The size of this data is around the same order of magnitude of the non-demangled ones. However, this is notably more than the demangling code (see previous point), e.g. 120 KiB (uncompressed) in a small kernel.

This approach also brings the same concerns regarding modifying the backtrace printing (see previous point).

# Demangling at compile-time and substituting symbols by hashes

One variation of the previous alternative is avoiding the mangled names inside the kernel, by hashing them. This would avoid having to support "big symbols" and would also reduce the size of the kallsyms tables, while still allowing to link modules.

However, if we do not have the real symbols around, then we do not have the possibility of providing both the mangled and demangled versions in the backtrace, which brings us back to the issues related to breaking userspace tools. There are also other places other than backtraces using "real" symbols that users may be relying on, such as /proc/*/stack.

 scripts/decode_stacktrace.sh | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

scripts/decode_stacktrace.sh +14 -0

index 5fbad61fe490..f3c7b506d440 100755
@@ -8,6 +8,14 @@ usage() {
 	echo "	$0 -r <release> | <vmlinux> [<base path>|auto] [<modules path>]"
 }
 
+# Try to find a Rust demangler
+if type llvm-cxxfilt >/dev/null 2>&1 ; then
+	cppfilt=llvm-cxxfilt
+elif type c++filt >/dev/null 2>&1 ; then
+	cppfilt=c++filt
+	cppfilt_opts=-i
+fi
+
 if [[ $1 == "-r" ]] ; then
 	vmlinux=""
 	basepath="auto"

@@ -169,6 +177,12 @@ parse_symbol() {
 	# In the case of inlines, move everything to same line
 	code=${code//$'\n'/' '}
 
+	# Demangle if the name looks like a Rust symbol and if
+	# we got a Rust demangler
+	if [[ $name =~ ^_R && $cppfilt != "" ]] ; then
+		name=$("$cppfilt" "$cppfilt_opts" "$name")
+	fi
+
 	# Replace old address with pretty line numbers
 	symbol="$segment$name ($code)"
 }

Signature · 1 line

2.34.1

Miguel Ojeda

author maintainer

2022-01-17 05:36 UTC #14 lore raw

PATCH v3 14/19 docs: add Rust documentation

Most of the documentation for Rust is written within the source code itself, as it is idiomatic for Rust projects. This applies to both the shared infrastructure at rust/ as well as any other Rust module (e.g. drivers) written across the kernel.

However, these documents contain general information that does not fit particularly well in the source code, like the Quick Start guide.

It also contains a few binary assets used for the rustdoc target and a few other small changes elsewhere in the documentation folder.

Co-developed-by Alex Gaynor <[email protected]>

Signed-off-by Alex Gaynor <[email protected]>

Co-developed-by Finn Behrens <[email protected]>

Co-developed-by Adam Bratschi-Kaye <[email protected]>

Signed-off-by Adam Bratschi-Kaye <[email protected]>

Co-developed-by Wedson Almeida Filho <[email protected]>

Signed-off-by Wedson Almeida Filho <[email protected]>

Co-developed-by Michael Ellerman <[email protected]>

Signed-off-by Michael Ellerman <[email protected]>

Co-developed-by Sven Van Asbroeck <[email protected]>

Signed-off-by Sven Van Asbroeck <[email protected]>

Co-developed-by Wu XiangCheng <[email protected]>

Signed-off-by Wu XiangCheng <[email protected]>

Co-developed-by Gary Guo <[email protected]>

Signed-off-by Gary Guo <[email protected]>

Co-developed-by Boris-Chengbiao Zhou <[email protected]>

Signed-off-by Boris-Chengbiao Zhou <[email protected]>

Co-developed-by Yuki Okushi <[email protected]>

Signed-off-by Yuki Okushi <[email protected]>

Co-developed-by Wei Liu <[email protected]>

Signed-off-by Wei Liu <[email protected]>

Co-developed-by Daniel Xu <[email protected]>

Signed-off-by Daniel Xu <[email protected]>

---
 Documentation/doc-guide/kernel-doc.rst      |   3 +
 Documentation/index.rst                     |   1 +
 Documentation/kbuild/kbuild.rst             |   4 +
 Documentation/process/changes.rst           |  42 ++++
 Documentation/rust/arch-support.rst         |  35 +++
 Documentation/rust/assets/favicon-16x16.png | Bin 0 -> 798 bytes
 Documentation/rust/assets/favicon-32x32.png | Bin 0 -> 2076 bytes
 Documentation/rust/assets/rust-logo.png     | Bin 0 -> 53976 bytes
 Documentation/rust/coding-guidelines.rst    | 151 +++++++++++++
 Documentation/rust/general-information.rst  |  80 +++++++
 Documentation/rust/index.rst                |  21 ++
 Documentation/rust/quick-start.rst          | 231 ++++++++++++++++++++
 12 files changed, 568 insertions(+)
 create mode 100644 Documentation/rust/arch-support.rst
 create mode 100644 Documentation/rust/assets/favicon-16x16.png
 create mode 100644 Documentation/rust/assets/favicon-32x32.png
 create mode 100644 Documentation/rust/assets/rust-logo.png
 create mode 100644 Documentation/rust/coding-guidelines.rst
 create mode 100644 Documentation/rust/general-information.rst
 create mode 100644 Documentation/rust/index.rst
 create mode 100644 Documentation/rust/quick-start.rst

Documentation/doc-guide/kernel-doc.rst +3 -0

index 79aaa55d6bcf..724e2ffddff1 100644
@@ -11,6 +11,9 @@ when it is embedded in source files.
    reasons. The kernel source contains tens of thousands of kernel-doc
    comments. Please stick to the style described here.
 
+.. note:: kernel-doc does not cover Rust code: please see
+   Documentation/rust/docs.rst instead.
+
 The kernel-doc structure is extracted from the comments, and proper
 `Sphinx C Domain`_ function and type descriptions with anchors are
 generated from them. The descriptions are filtered for special kernel-doc

Documentation/index.rst +1 -0

index 54ce34fd6fbd..1b13c2445e87 100644
@@ -82,6 +82,7 @@ merged much easier.
    maintainer/index
    fault-injection/index
    livepatch/index
+   rust/index
 
 
 Kernel API documentation

Documentation/kbuild/kbuild.rst +4 -0

index 2d1fc03d346e..468a0d216c29 100644
@@ -57,6 +57,10 @@ CFLAGS_MODULE
 -------------
 Additional module specific options to use for $(CC).
 
+KRUSTFLAGS
+----------
+Additional options to the Rust compiler (for built-in and modules).
+
 LDFLAGS_MODULE
 --------------
 Additional options used for $(LD) when linking modules.

Documentation/process/changes.rst +42 -0

66 lines not on this page · raw message

Documentation/rust/arch-support.rst new file +35 -0

new file mode 100644
index 000000000000..fdcce6452623
@@ -0,0 +1,35 @@
+.. _rust_arch_support:
+
+Arch Support
+============
+
+Currently, the Rust compiler (``rustc``) uses LLVM for code generation,
+which limits the supported architectures that can be targeted. In addition,
+support for building the kernel with LLVM/Clang varies (see :ref:`kbuild_llvm`).
+This support is needed for ``bindgen`` which uses ``libclang``.
+
+Below is a general summary of architectures that currently work. Level of
+support corresponds to ``S`` values in the ``MAINTAINERS`` file.
+
+.. list-table::
+   :widths: 10 10 10
+   :header-rows: 1
+
+   * - Architecture
+     - Level of support
+     - Constraints
+   * - ``arm``
+     - Maintained
+     - ``armv6`` and compatible only, ``RUST_OPT_LEVEL >= 2``
+   * - ``arm64``
+     - Maintained
+     - None
+   * - ``powerpc``
+     - Maintained
+     - ``ppc64le`` only, ``RUST_OPT_LEVEL < 2`` requires ``CONFIG_THREAD_SHIFT=15``
+   * - ``riscv``
+     - Maintained
+     - ``riscv64`` only
+   * - ``x86``
+     - Maintained
+     - ``x86_64`` only

Documentation/rust/assets/favicon-16x16.png new file binary +0 -0

new file mode 100644
index 0000000000000000000000000000000000000000..d93115e8f47a939635b73ad3b3226837f83f7584
GIT binary patch

Documentation/rust/assets/favicon-32x32.png new file binary +0 -0

new file mode 100644
index 0000000000000000000000000000000000000000..655ccbcfc8cddde1e9c7d826a3f44c1e056b1dc8
GIT binary patch

Documentation/rust/assets/rust-logo.png new file binary +0 -0

new file mode 100644
index 0000000000000000000000000000000000000000..081ae80c193ba259ffc5c506ccefc4cedd915c4b
GIT binary patch

Documentation/rust/coding-guidelines.rst new file +151 -0

151 lines not on this page · raw message

Documentation/rust/general-information.rst new file +80 -0

80 lines not on this page · raw message

Documentation/rust/index.rst new file +21 -0

new file mode 100644
index 000000000000..6e20af5b723a
@@ -0,0 +1,21 @@
+Rust
+====
+
+Documentation related to Rust within the kernel. To start using Rust
+in the kernel, please read the
+:ref:`Documentation/rust/quick-start.rst <rust_quick_start>` guide.
+
+.. toctree::
+    :maxdepth: 1
+
+    quick-start
+    general-information
+    coding-guidelines
+    arch-support
+
+.. only::  subproject and html
+
+   Indices
+   =======
+
+   * :ref:`genindex`

Documentation/rust/quick-start.rst new file +231 -0

231 lines not on this page · raw message

Signature · 1 line

2.34.1

Jonathan Corbet

maintainer

2022-01-18 22:33 UTC #15 lore raw

Re: [PATCH v3 14/19] docs: add Rust documentation

Quoted 10 lines · Miguel Ojeda

Most of the documentation for Rust is written within the source code itself, as it is idiomatic for Rust projects. This applies to both the shared infrastructure at rust/ as well as any other Rust module (e.g. drivers) written across the kernel.
However, these documents contain general information that does not fit particularly well in the source code, like the Quick Start guide.
It also contains a few binary assets used for the rustdoc target and a few other small changes elsewhere in the documentation folder.

Glad to see documentation!

That said, I have one little request...

Quoted 8 lines

 Documentation/doc-guide/kernel-doc.rst      |   3 +
 Documentation/index.rst                     |   1 +
 Documentation/kbuild/kbuild.rst             |   4 +
 Documentation/process/changes.rst           |  42 ++++
 Documentation/rust/arch-support.rst         |  35 +++
 Documentation/rust/assets/favicon-16x16.png | Bin 0 -> 798 bytes
 Documentation/rust/assets/favicon-32x32.png | Bin 0 -> 2076 bytes
 Documentation/rust/assets/rust-logo.png     | Bin 0 -> 53976 bytes

We have really tried to keep binary files (like PNG images) out of the documentation tree. If we really need these images, can they be provided in SVG form?

Thanks,

jon

Miguel Ojeda

2022-01-19 13:59 UTC #16 lore raw

Re: [PATCH v3 14/19] docs: add Rust documentation

Quoted 4 lines · Jonathan Corbet

We have really tried to keep binary files (like PNG images) out of the documentation tree. If we really need these images, can they be provided in SVG form?

Yeah, they are not critical -- I can change them to a single SVG, or use Tux, or drop them (although it is a nice way to tell one is not in the Rust standard library docs).

Is there a preferred SVG version of Tux? (I cannot find one in the tree, only the GIF one at Doc/logo.gif). If not, perhaps we could ask permission to integrate one like https://github.com/garrett/Tux.

Cheers,
Miguel

Miguel Ojeda

author maintainer

2022-01-17 05:35 UTC #17 lore raw

PATCH v3 15/19 Kbuild: add Rust support

Having all the new files in place, we now enable Rust support in the build system, including Kconfig entries related to Rust, the Rust configuration printer, the target definition files, the version detection script and a few other bits.

In the future, we will likely want to generate the target files on the fly via a script.

Co-developed-by Alex Gaynor <[email protected]>

Signed-off-by Alex Gaynor <[email protected]>

Co-developed-by Finn Behrens <[email protected]>

Co-developed-by Adam Bratschi-Kaye <[email protected]>

Signed-off-by Adam Bratschi-Kaye <[email protected]>

Co-developed-by Wedson Almeida Filho <[email protected]>

Signed-off-by Wedson Almeida Filho <[email protected]>

Co-developed-by Michael Ellerman <[email protected]>

Signed-off-by Michael Ellerman <[email protected]>

Co-developed-by Sven Van Asbroeck <[email protected]>

Signed-off-by Sven Van Asbroeck <[email protected]>

Co-developed-by Gary Guo <[email protected]>

Signed-off-by Gary Guo <[email protected]>

Co-developed-by Boris-Chengbiao Zhou <[email protected]>

Signed-off-by Boris-Chengbiao Zhou <[email protected]>

Co-developed-by Boqun Feng <[email protected]>

Signed-off-by Boqun Feng <[email protected]>

Co-developed-by Douglas Su <[email protected]>

Signed-off-by Douglas Su <[email protected]>

Co-developed-by Dariusz Sosnowski <[email protected]>

Signed-off-by Dariusz Sosnowski <[email protected]>

Co-developed-by Antonio Terceiro <[email protected]>

Signed-off-by Antonio Terceiro <[email protected]>

Co-developed-by Daniel Xu <[email protected]>

Signed-off-by Daniel Xu <[email protected]>

---
 .gitignore                                   |   5 +
 .rustfmt.toml                                |  12 +
 Makefile                                     | 152 +++++++-
 arch/arm/rust/target.json                    |  27 ++
 arch/arm64/rust/target.json                  |  34 ++
 arch/powerpc/rust/target.json                |  29 ++
 arch/riscv/Makefile                          |   1 +
 arch/riscv/rust/rv32ima.json                 |  36 ++
 arch/riscv/rust/rv32imac.json                |  36 ++
 arch/riscv/rust/rv64ima.json                 |  36 ++
 arch/riscv/rust/rv64imac.json                |  36 ++
 arch/x86/rust/target.json                    |  36 ++
 init/Kconfig                                 |  44 ++-
 lib/Kconfig.debug                            | 144 ++++++++
 rust/.gitignore                              |   7 +
 rust/Makefile                                | 352 +++++++++++++++++++
 rust/bindgen_parameters                      |  13 +
 scripts/Kconfig.include                      |   6 +-
 scripts/Makefile.build                       |  22 ++
 scripts/Makefile.debug                       |  10 +
 scripts/Makefile.lib                         |  12 +
 scripts/Makefile.modfinal                    |   8 +-
 scripts/cc-version.sh                        |  12 +-
 scripts/is_rust_module.sh                    |  19 +
 scripts/kconfig/confdata.c                   |  75 ++++
 scripts/min-tool-version.sh                  |   6 +
 scripts/rust-is-available-bindgen-libclang.h |   2 +
 scripts/rust-is-available.sh                 | 159 +++++++++
 28 files changed, 1310 insertions(+), 21 deletions(-)
 create mode 100644 .rustfmt.toml
 create mode 100644 arch/arm/rust/target.json
 create mode 100644 arch/arm64/rust/target.json
 create mode 100644 arch/powerpc/rust/target.json
 create mode 100644 arch/riscv/rust/rv32ima.json
 create mode 100644 arch/riscv/rust/rv32imac.json
 create mode 100644 arch/riscv/rust/rv64ima.json
 create mode 100644 arch/riscv/rust/rv64imac.json
 create mode 100644 arch/x86/rust/target.json
 create mode 100644 rust/.gitignore
 create mode 100644 rust/Makefile
 create mode 100644 rust/bindgen_parameters
 create mode 100755 scripts/is_rust_module.sh
 create mode 100644 scripts/rust-is-available-bindgen-libclang.h
 create mode 100755 scripts/rust-is-available.sh

.gitignore +5 -0

index 7afd412dadd2..48c68948f476 100644
@@ -37,6 +37,7 @@
 *.o
 *.o.*
 *.patch
+*.rmeta
 *.s
 *.so
 *.so.dbg

@@ -96,6 +97,7 @@ modules.order
 !.gitattributes
 !.gitignore
 !.mailmap
+!.rustfmt.toml
 
 #
 # Generated include files

@@ -161,3 +163,6 @@ x509.genkey
 
 # Documentation toolchain
 sphinx_*/
+
+# Rust analyzer configuration
+/rust-project.json

.rustfmt.toml new file +12 -0

new file mode 100644
index 000000000000..3de5cc497465
@@ -0,0 +1,12 @@
+edition = "2021"
+newline_style = "Unix"
+
+# Unstable options that help catching some mistakes in formatting and that we may want to enable
+# when they become stable.
+#
+# They are kept here since they are useful to run from time to time.
+#format_code_in_doc_comments = true
+#reorder_impl_items = true
+#comment_width = 100
+#wrap_comments = true
+#normalize_comments = true

Makefile +144 -8

280 lines not on this page · raw message

arch/arm/rust/target.json new file +27 -0

new file mode 100644
index 000000000000..3f845b8221dc
@@ -0,0 +1,27 @@
+{
+  "arch": "arm",
+  "crt-static-respected": true,
+  "data-layout": "e-m:e-p:32:32-Fi8-i64:64-v128:64:128-a:0:32-n32-S64",
+  "dynamic-linking": true,
+  "env": "gnu",
+  "executables": true,
+  "features": "+strict-align,+v6",
+  "function-sections": false,
+  "has-elf-tls": true,
+  "has-rpath": true,
+  "linker-is-gnu": true,
+  "llvm-target": "arm-unknown-linux-gnueabi",
+  "max-atomic-width": 64,
+  "os": "linux",
+  "position-independent-executables": true,
+  "pre-link-args": {
+    "gcc": [
+      "-Wl,--as-needed",
+      "-Wl,-z,noexecstack"
+    ]
+  },
+  "relocation-model": "static",
+  "target-family": "unix",
+  "target-mcount": "\u0001__gnu_mcount_nc",
+  "target-pointer-width": "32"
+}

arch/arm64/rust/target.json new file +34 -0

new file mode 100644
index 000000000000..09a264df26c7
@@ -0,0 +1,34 @@
+{
+  "arch": "aarch64",
+  "data-layout": "e-m:e-i8:8:32-i16:16:32-i64:64-i128:128-n32:64-S128",
+  "disable-redzone": true,
+  "emit-debug-gdb-scripts": false,
+  "env": "gnu",
+  "features": "+strict-align,+neon,+fp-armv8",
+  "frame-pointer": "always",
+  "function-sections": false,
+  "linker-flavor": "gcc",
+  "linker-is-gnu": true,
+  "llvm-target": "aarch64-unknown-none",
+  "max-atomic-width": 128,
+  "needs-plt": true,
+  "os": "none",
+  "panic-strategy": "abort",
+  "position-independent-executables": true,
+  "pre-link-args": {
+    "gcc": [
+      "-Wl,--as-needed",
+      "-Wl,-z,noexecstack",
+      "-m64"
+    ]
+  },
+  "relocation-model": "static",
+  "relro-level": "full",
+  "stack-probes": {
+    "kind": "none"
+  },
+  "target-c-int-width": "32",
+  "target-endian": "little",
+  "target-pointer-width": "64",
+  "vendor": ""
+}

arch/powerpc/rust/target.json new file +29 -0

new file mode 100644
index 000000000000..2420c8e6a520
@@ -0,0 +1,29 @@
+{
+  "arch": "powerpc64",
+  "code-model": "large",
+  "cpu": "ppc64le",
+  "data-layout": "e-m:e-i64:64-n32:64",
+  "env": "gnu",
+  "features": "-altivec,-vsx,-hard-float",
+  "function-sections": false,
+  "linker-flavor": "gcc",
+  "linker-is-gnu": true,
+  "llvm-target": "powerpc64le-elf",
+  "max-atomic-width": 64,
+  "os": "none",
+  "panic-strategy": "abort",
+  "position-independent-executables": true,
+  "pre-link-args": {
+    "gcc": [
+      "-Wl,--as-needed",
+      "-Wl,-z,noexecstack",
+      "-m64"
+    ]
+  },
+  "relocation-model": "static",
+  "relro-level": "full",
+  "target-family": "unix",
+  "target-mcount": "_mcount",
+  "target-endian": "little",
+  "target-pointer-width": "64"
+}

arch/riscv/Makefile +1 -0

index 8a107ed18b0d..0487db1e54c6 100644
@@ -52,6 +52,7 @@ riscv-march-$(CONFIG_FPU)		:= $(riscv-march-y)fd
 riscv-march-$(CONFIG_RISCV_ISA_C)	:= $(riscv-march-y)c
 KBUILD_CFLAGS += -march=$(subst fd,,$(riscv-march-y))
 KBUILD_AFLAGS += -march=$(riscv-march-y)
+KBUILD_RUST_TARGET := $(srctree)/arch/riscv/rust/$(subst fd,,$(riscv-march-y)).json
 
 KBUILD_CFLAGS += -mno-save-restore
 KBUILD_CFLAGS += -DCONFIG_PAGE_OFFSET=$(CONFIG_PAGE_OFFSET)

arch/riscv/rust/rv32ima.json new file +36 -0

new file mode 100644
index 000000000000..bcdda88c1604
@@ -0,0 +1,36 @@
+{
+  "arch": "riscv32",
+  "code-model": "medium",
+  "cpu": "generic-rv32",
+  "data-layout": "e-m:e-p:32:32-i64:64-n32-S128",
+  "disable-redzone": true,
+  "emit-debug-gdb-scripts": false,
+  "env": "gnu",
+  "features": "+m,+a",
+  "frame-pointer": "always",
+  "function-sections": false,
+  "linker-flavor": "gcc",
+  "linker-is-gnu": true,
+  "llvm-target": "riscv32",
+  "max-atomic-width": 32,
+  "needs-plt": true,
+  "os": "none",
+  "panic-strategy": "abort",
+  "position-independent-executables": true,
+  "pre-link-args": {
+    "gcc": [
+      "-Wl,--as-needed",
+      "-Wl,-z,noexecstack",
+      "-m32"
+    ]
+  },
+  "relocation-model": "static",
+  "relro-level": "full",
+  "stack-probes": {
+    "kind": "none"
+  },
+  "target-c-int-width": "32",
+  "target-endian": "little",
+  "target-pointer-width": "32",
+  "vendor": ""
+}

arch/riscv/rust/rv32imac.json new file +36 -0

new file mode 100644
index 000000000000..45873c10a5c3
@@ -0,0 +1,36 @@
+{
+  "arch": "riscv32",
+  "code-model": "medium",
+  "cpu": "generic-rv32",
+  "data-layout": "e-m:e-p:32:32-i64:64-n32-S128",
+  "disable-redzone": true,
+  "emit-debug-gdb-scripts": false,
+  "env": "gnu",
+  "features": "+m,+a,+c",
+  "frame-pointer": "always",
+  "function-sections": false,
+  "linker-flavor": "gcc",
+  "linker-is-gnu": true,
+  "llvm-target": "riscv32",
+  "max-atomic-width": 32,
+  "needs-plt": true,
+  "os": "none",
+  "panic-strategy": "abort",
+  "position-independent-executables": true,
+  "pre-link-args": {
+    "gcc": [
+      "-Wl,--as-needed",
+      "-Wl,-z,noexecstack",
+      "-m32"
+    ]
+  },
+  "relocation-model": "static",
+  "relro-level": "full",
+  "stack-probes": {
+    "kind": "none"
+  },
+  "target-c-int-width": "32",
+  "target-endian": "little",
+  "target-pointer-width": "32",
+  "vendor": ""
+}

arch/riscv/rust/rv64ima.json new file +36 -0

new file mode 100644
index 000000000000..853d758c5461
@@ -0,0 +1,36 @@
+{
+  "arch": "riscv64",
+  "code-model": "medium",
+  "cpu": "generic-rv64",
+  "data-layout": "e-m:e-p:64:64-i64:64-i128:128-n64-S128",
+  "disable-redzone": true,
+  "emit-debug-gdb-scripts": false,
+  "env": "gnu",
+  "features": "+m,+a",
+  "frame-pointer": "always",
+  "function-sections": false,
+  "linker-flavor": "gcc",
+  "linker-is-gnu": true,
+  "llvm-target": "riscv64",
+  "max-atomic-width": 64,
+  "needs-plt": true,
+  "os": "none",
+  "panic-strategy": "abort",
+  "position-independent-executables": true,
+  "pre-link-args": {
+    "gcc": [
+      "-Wl,--as-needed",
+      "-Wl,-z,noexecstack",
+      "-m64"
+    ]
+  },
+  "relocation-model": "static",
+  "relro-level": "full",
+  "stack-probes": {
+    "kind": "none"
+  },
+  "target-c-int-width": "32",
+  "target-endian": "little",
+  "target-pointer-width": "64",
+  "vendor": ""
+}

arch/riscv/rust/rv64imac.json new file +36 -0

new file mode 100644
index 000000000000..ce50ee8e8c93
@@ -0,0 +1,36 @@
+{
+  "arch": "riscv64",
+  "code-model": "medium",
+  "cpu": "generic-rv64",
+  "data-layout": "e-m:e-p:64:64-i64:64-i128:128-n64-S128",
+  "disable-redzone": true,
+  "emit-debug-gdb-scripts": false,
+  "env": "gnu",
+  "features": "+m,+a,+c",
+  "frame-pointer": "always",
+  "function-sections": false,
+  "linker-flavor": "gcc",
+  "linker-is-gnu": true,
+  "llvm-target": "riscv64",
+  "max-atomic-width": 64,
+  "needs-plt": true,
+  "os": "none",
+  "panic-strategy": "abort",
+  "position-independent-executables": true,
+  "pre-link-args": {
+    "gcc": [
+      "-Wl,--as-needed",
+      "-Wl,-z,noexecstack",
+      "-m64"
+    ]
+  },
+  "relocation-model": "static",
+  "relro-level": "full",
+  "stack-probes": {
+    "kind": "none"
+  },
+  "target-c-int-width": "32",
+  "target-endian": "little",
+  "target-pointer-width": "64",
+  "vendor": ""
+}

arch/x86/rust/target.json new file +36 -0

new file mode 100644
index 000000000000..379cf39e8941
@@ -0,0 +1,36 @@
+{
+  "arch": "x86_64",
+  "code-model": "kernel",
+  "cpu": "x86-64",
+  "data-layout": "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128",
+  "disable-redzone": true,
+  "emit-debug-gdb-scripts": false,
+  "env": "gnu",
+  "features": "-mmx,-sse,-sse2,-sse3,-ssse3,-sse4.1,-sse4.2,-3dnow,-3dnowa,-avx,-avx2,+soft-float",
+  "frame-pointer": "always",
+  "function-sections": false,
+  "linker-flavor": "gcc",
+  "linker-is-gnu": true,
+  "llvm-target": "x86_64-elf",
+  "max-atomic-width": 64,
+  "needs-plt": true,
+  "os": "none",
+  "panic-strategy": "abort",
+  "position-independent-executables": true,
+  "pre-link-args": {
+    "gcc": [
+      "-Wl,--as-needed",
+      "-Wl,-z,noexecstack",
+      "-m64"
+    ]
+  },
+  "relocation-model": "static",
+  "relro-level": "full",
+  "stack-probes": {
+    "kind": "none"
+  },
+  "target-c-int-width": "32",
+  "target-endian": "little",
+  "target-pointer-width": "64",
+  "vendor": "unknown"
+}

init/Kconfig +43 -1

62 lines not on this page · raw message

lib/Kconfig.debug +144 -0

150 lines not on this page · raw message

rust/.gitignore new file +7 -0

new file mode 100644
index 000000000000..168cb26a31b9
@@ -0,0 +1,7 @@
+# SPDX-License-Identifier: GPL-2.0
+
+bindings_generated.rs
+bindings_helpers_generated.rs
+exports_*_generated.h
+doc/
+test/

rust/Makefile new file +352 -0

352 lines not on this page · raw message

rust/bindgen_parameters new file +13 -0

new file mode 100644
index 000000000000..c2cc4a88234e
@@ -0,0 +1,13 @@
+# SPDX-License-Identifier: GPL-2.0
+
+--opaque-type xregs_state
+--opaque-type desc_struct
+--opaque-type arch_lbr_state
+--opaque-type local_apic
+
+# If SMP is disabled, `arch_spinlock_t` is defined as a ZST which triggers a Rust
+# warning. We don't need to peek into it anyway.
+--opaque-type spinlock
+
+# `seccomp`'s comment gets understood as a doctest
+--no-doc-comments

scripts/Kconfig.include +3 -3

index 0496efd6e117..83e850321eb6 100644
@@ -36,12 +36,12 @@ ld-option = $(success,$(LD) -v $(1))
 as-instr = $(success,printf "%b\n" "$(1)" | $(CC) $(CLANG_FLAGS) -c -x assembler -o /dev/null -)
 
 # check if $(CC) and $(LD) exist
-$(error-if,$(failure,command -v $(CC)),compiler '$(CC)' not found)
+$(error-if,$(failure,command -v $(CC)),C compiler '$(CC)' not found)
 $(error-if,$(failure,command -v $(LD)),linker '$(LD)' not found)
 
-# Get the compiler name, version, and error out if it is not supported.
+# Get the C compiler name, version, and error out if it is not supported.
 cc-info := $(shell,$(srctree)/scripts/cc-version.sh $(CC))
-$(error-if,$(success,test -z "$(cc-info)"),Sorry$(comma) this compiler is not supported.)
+$(error-if,$(success,test -z "$(cc-info)"),Sorry$(comma) this C compiler is not supported.)
 cc-name := $(shell,set -- $(cc-info) && echo $1)
 cc-version := $(shell,set -- $(cc-info) && echo $2)

scripts/Makefile.build +22 -0

index 78656b527fe5..7adac231fafd 100644
@@ -26,6 +26,7 @@ EXTRA_CPPFLAGS :=
 EXTRA_LDFLAGS  :=
 asflags-y  :=
 ccflags-y  :=
+rustflags-y :=
 cppflags-y :=
 ldflags-y  :=

@@ -323,6 +324,27 @@ quiet_cmd_cc_lst_c = MKLST   $@
 $(obj)/%.lst: $(src)/%.c FORCE
 	$(call if_changed_dep,cc_lst_c)
 
+# Compile Rust sources (.rs)
+# ---------------------------------------------------------------------------
+
+# Need to use absolute path here and have symbolic links resolved;
+# otherwise rustdoc and rustc compute different hashes for the target.
+rust_cross_flags := --target=$(realpath $(KBUILD_RUST_TARGET))
+
+quiet_cmd_rustc_o_rs = $(RUSTC_OR_CLIPPY_QUIET) $(quiet_modtag) $@
+      cmd_rustc_o_rs = \
+	RUST_MODFILE=$(modfile) \
+	$(RUSTC_OR_CLIPPY) $(rust_flags) $(rust_cross_flags) \
+		-Zallow-features=allocator_api,bench_black_box,concat_idents,generic_associated_types,global_asm \
+		--extern alloc --extern kernel \
+		--crate-type rlib --out-dir $(obj) -L $(objtree)/rust/ \
+		--crate-name $(patsubst %.o,%,$(notdir $@)) $<; \
+	mv $(obj)/$(subst .o,,$(notdir $@)).d $(depfile); \
+	sed -i '/^\#/d' $(depfile)
+
+$(obj)/%.o: $(src)/%.rs FORCE
+	$(call if_changed_dep,rustc_o_rs)
+
 # Compile assembler sources (.S)
 # ---------------------------------------------------------------------------

scripts/Makefile.debug +10 -0

index 9f39b0130551..fe87389d52c0 100644
@@ -1,4 +1,5 @@
 DEBUG_CFLAGS	:=
+DEBUG_RUSTFLAGS	:=
 
 ifdef CONFIG_DEBUG_INFO_SPLIT
 DEBUG_CFLAGS	+= -gsplit-dwarf

@@ -10,6 +11,12 @@ ifndef CONFIG_AS_IS_LLVM
 KBUILD_AFLAGS	+= -Wa,-gdwarf-2
 endif
 
+ifdef CONFIG_DEBUG_INFO_REDUCED
+DEBUG_RUSTFLAGS += -Cdebuginfo=1
+else
+DEBUG_RUSTFLAGS += -Cdebuginfo=2
+endif
+
 ifndef CONFIG_DEBUG_INFO_DWARF_TOOLCHAIN_DEFAULT
 dwarf-version-$(CONFIG_DEBUG_INFO_DWARF4) := 4
 dwarf-version-$(CONFIG_DEBUG_INFO_DWARF5) := 5

@@ -31,3 +38,6 @@ endif
 
 KBUILD_CFLAGS += $(DEBUG_CFLAGS)
 export DEBUG_CFLAGS
+
+KBUILD_RUSTFLAGS += $(DEBUG_RUSTFLAGS)
+export DEBUG_RUSTFLAGS

scripts/Makefile.lib +12 -0

index d1f865b8c0cb..ce6142238835 100644
@@ -8,6 +8,7 @@ ldflags-y  += $(EXTRA_LDFLAGS)
 # flags that take effect in current and sub directories
 KBUILD_AFLAGS += $(subdir-asflags-y)
 KBUILD_CFLAGS += $(subdir-ccflags-y)
+KBUILD_RUSTFLAGS += $(subdir-rustflags-y)
 
 # Figure out what we need to build from the various variables
 # ===========================================================================

@@ -133,6 +134,10 @@ _c_flags       = $(filter-out $(CFLAGS_REMOVE_$(target-stem).o), \
                      $(filter-out $(ccflags-remove-y), \
                          $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) $(ccflags-y)) \
                      $(CFLAGS_$(target-stem).o))
+_rust_flags    = $(filter-out $(RUSTFLAGS_REMOVE_$(target-stem).o), \
+                     $(filter-out $(rustflags-remove-y), \
+                         $(KBUILD_RUSTFLAGS) $(rustflags-y)) \
+                     $(RUSTFLAGS_$(target-stem).o))
 _a_flags       = $(filter-out $(AFLAGS_REMOVE_$(target-stem).o), \
                      $(filter-out $(asflags-remove-y), \
                          $(KBUILD_CPPFLAGS) $(KBUILD_AFLAGS) $(asflags-y)) \

@@ -202,6 +207,11 @@ modkern_cflags =                                          \
 		$(KBUILD_CFLAGS_MODULE) $(CFLAGS_MODULE), \
 		$(KBUILD_CFLAGS_KERNEL) $(CFLAGS_KERNEL) $(modfile_flags))
 
+modkern_rustflags =                                              \
+	$(if $(part-of-module),                                   \
+		$(KBUILD_RUSTFLAGS_MODULE) $(RUSTFLAGS_MODULE), \
+		$(KBUILD_RUSTFLAGS_KERNEL) $(RUSTFLAGS_KERNEL))
+
 modkern_aflags = $(if $(part-of-module),				\
 			$(KBUILD_AFLAGS_MODULE) $(AFLAGS_MODULE),	\
 			$(KBUILD_AFLAGS_KERNEL) $(AFLAGS_KERNEL))

@@ -211,6 +221,8 @@ c_flags        = -Wp,-MMD,$(depfile) $(NOSTDINC_FLAGS) $(LINUXINCLUDE)     \
 		 $(_c_flags) $(modkern_cflags)                           \
 		 $(basename_flags) $(modname_flags)
 
+rust_flags     = $(_rust_flags) $(modkern_rustflags) @$(objtree)/include/generated/rustc_cfg
+
 a_flags        = -Wp,-MMD,$(depfile) $(NOSTDINC_FLAGS) $(LINUXINCLUDE)     \
 		 $(_a_flags) $(modkern_aflags)

scripts/Makefile.modfinal +5 -3

index 7f39599e9fae..0518b6d3e620 100644
@@ -39,11 +39,13 @@ quiet_cmd_ld_ko_o = LD [M]  $@
 
 quiet_cmd_btf_ko = BTF [M] $@
       cmd_btf_ko = 							\
-	if [ -f vmlinux ]; then						\
+	if [ ! -f vmlinux ]; then					\
+		printf "Skipping BTF generation for %s due to unavailability of vmlinux\n" $@ 1>&2; \
+	elif $(srctree)/scripts/is_rust_module.sh $@; then 		\
+		printf "Skipping BTF generation for %s because it's a Rust module\n" $@ 1>&2; \
+	else								\
 		LLVM_OBJCOPY="$(OBJCOPY)" $(PAHOLE) -J $(PAHOLE_FLAGS) --btf_base vmlinux $@; \
 		$(RESOLVE_BTFIDS) -b vmlinux $@; 			\
-	else								\
-		printf "Skipping BTF generation for %s due to unavailability of vmlinux\n" $@ 1>&2; \
 	fi;
 
 # Same as newer-prereqs, but allows to exclude specified extra dependencies

scripts/cc-version.sh +6 -6

index f1952c522466..2401c86fcf53 100755
@@ -1,13 +1,13 @@
 #!/bin/sh
 # SPDX-License-Identifier: GPL-2.0
 #
-# Print the compiler name and its version in a 5 or 6-digit form.
+# Print the C compiler name and its version in a 5 or 6-digit form.
 # Also, perform the minimum version check.
 
 set -e
 
-# Print the compiler name and some version components.
-get_compiler_info()
+# Print the C compiler name and some version components.
+get_c_compiler_info()
 {
 	cat <<- EOF | "$@" -E -P -x c - 2>/dev/null
 	#if defined(__clang__)

@@ -32,7 +32,7 @@ get_canonical_version()
 
 # $@ instead of $1 because multiple words might be given, e.g. CC="ccache gcc".
 orig_args="$@"
-set -- $(get_compiler_info "$@")
+set -- $(get_c_compiler_info "$@")
 
 name=$1

@@ -52,7 +52,7 @@ ICC)
 	min_version=$($min_tool_version icc)
 	;;
 *)
-	echo "$orig_args: unknown compiler" >&2
+	echo "$orig_args: unknown C compiler" >&2
 	exit 1
 	;;
 esac

@@ -62,7 +62,7 @@ min_cversion=$(get_canonical_version $min_version)
 
 if [ "$cversion" -lt "$min_cversion" ]; then
 	echo >&2 "***"
-	echo >&2 "*** Compiler is too old."
+	echo >&2 "*** C compiler is too old."
 	echo >&2 "***   Your $name version:    $version"
 	echo >&2 "***   Minimum $name version: $min_version"
 	echo >&2 "***"

scripts/is_rust_module.sh new file +19 -0

new file mode 100755
index 000000000000..ff24d9c16f09
@@ -0,0 +1,19 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+#
+# is_rust_module.sh MOD.ko
+#
+# Returns 0 if MOD.ko is a rust module, 1 otherwise.
+
+set -e
+module="$*"
+
+while IFS= read -r line
+do
+  # Any symbol beginning with "_R" is a v0 mangled rust symbol
+  if [[ $line =~ ^[0-9a-fA-F]+[[:space:]]+[uUtTrR][[:space:]]+_R[^[:space:]]+$ ]]; then
+    exit 0
+  fi
+done < <(nm "$module")
+
+exit 1

scripts/kconfig/confdata.c +75 -0

99 lines not on this page · raw message

scripts/min-tool-version.sh +6 -0

index 4edc708baa63..05c95710d7e3 100755
@@ -31,6 +31,12 @@ llvm)
 		echo 10.0.1
 	fi
 	;;
+rustc)
+	echo 1.58.0
+	;;
+bindgen)
+	echo 0.56.0
+	;;
 *)
 	echo "$1: unknown tool" >&2
 	exit 1

scripts/rust-is-available-bindgen-libclang.h new file +2 -0

new file mode 100644
index 000000000000..0ef6db10d674
@@ -0,0 +1,2 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#pragma message("clang version " __clang_version__)

scripts/rust-is-available.sh new file +159 -0

159 lines not on this page · raw message

Signature · 1 line

2.34.1

Miguel Ojeda

author maintainer

2022-01-17 05:35 UTC #18 lore raw

PATCH v3 16/19 samples: add Rust examples

A set of Rust modules that showcase how Rust modules look like and how to use the abstracted kernel features.

These samples also double as tests in the CI.

The semaphore sample comes with a C version for comparison.

Co-developed-by Alex Gaynor <[email protected]>

Signed-off-by Alex Gaynor <[email protected]>

Co-developed-by Finn Behrens <[email protected]>

Co-developed-by Wedson Almeida Filho <[email protected]>

Signed-off-by Wedson Almeida Filho <[email protected]>

Co-developed-by Greg Kroah-Hartman <[email protected]>

Signed-off-by Greg Kroah-Hartman <[email protected]>

Co-developed-by Sven Van Asbroeck <[email protected]>

Signed-off-by Sven Van Asbroeck <[email protected]>

Co-developed-by Gary Guo <[email protected]>

Signed-off-by Gary Guo <[email protected]>

Co-developed-by Boris-Chengbiao Zhou <[email protected]>

Signed-off-by Boris-Chengbiao Zhou <[email protected]>

Co-developed-by Ayaan Zaidi <[email protected]>

Signed-off-by Ayaan Zaidi <[email protected]>

Co-developed-by Milan Landaverde <[email protected]>

Signed-off-by Milan Landaverde <[email protected]>

---
 samples/Kconfig                        |   2 +
 samples/Makefile                       |   1 +
 samples/rust/Kconfig                   | 123 ++++++++++++++
 samples/rust/Makefile                  |  13 ++
 samples/rust/rust_chrdev.rs            |  53 +++++++
 samples/rust/rust_minimal.rs           |  38 +++++
 samples/rust/rust_miscdev.rs           | 147 +++++++++++++++++
 samples/rust/rust_module_parameters.rs |  72 +++++++++
 samples/rust/rust_platform.rs          |  25 +++
 samples/rust/rust_print.rs             |  57 +++++++
 samples/rust/rust_random.rs            |  64 ++++++++
 samples/rust/rust_semaphore.rs         | 175 ++++++++++++++++++++
 samples/rust/rust_semaphore_c.c        | 212 +++++++++++++++++++++++++
 samples/rust/rust_stack_probing.rs     |  40 +++++
 samples/rust/rust_sync.rs              |  81 ++++++++++
 15 files changed, 1103 insertions(+)
 create mode 100644 samples/rust/Kconfig
 create mode 100644 samples/rust/Makefile
 create mode 100644 samples/rust/rust_chrdev.rs
 create mode 100644 samples/rust/rust_minimal.rs
 create mode 100644 samples/rust/rust_miscdev.rs
 create mode 100644 samples/rust/rust_module_parameters.rs
 create mode 100644 samples/rust/rust_platform.rs
 create mode 100644 samples/rust/rust_print.rs
 create mode 100644 samples/rust/rust_random.rs
 create mode 100644 samples/rust/rust_semaphore.rs
 create mode 100644 samples/rust/rust_semaphore_c.c
 create mode 100644 samples/rust/rust_stack_probing.rs
 create mode 100644 samples/rust/rust_sync.rs

samples/Kconfig +2 -0

index 43d2e9aa557f..a3a5166837b1 100644
@@ -241,6 +241,8 @@ config SAMPLE_WATCH_QUEUE
 	  Build example userspace program to use the new mount_notify(),
 	  sb_notify() syscalls and the KEYCTL_WATCH_KEY keyctl() function.
 
+source "samples/rust/Kconfig"
+
 endif # SAMPLES
 
 config HAVE_SAMPLE_FTRACE_DIRECT

samples/Makefile +1 -0

index 4bcd6b93bffa..d66f49a9f080 100644
@@ -32,3 +32,4 @@ obj-$(CONFIG_SAMPLE_INTEL_MEI)		+= mei/
 subdir-$(CONFIG_SAMPLE_WATCHDOG)	+= watchdog
 subdir-$(CONFIG_SAMPLE_WATCH_QUEUE)	+= watch_queue
 obj-$(CONFIG_DEBUG_KMEMLEAK_TEST)	+= kmemleak/
+obj-$(CONFIG_SAMPLES_RUST)		+= rust/

samples/rust/Kconfig new file +123 -0

123 lines not on this page · raw message

samples/rust/Makefile new file +13 -0

new file mode 100644
index 000000000000..96ffeb7d334a
@@ -0,0 +1,13 @@
+# SPDX-License-Identifier: GPL-2.0
+
+obj-$(CONFIG_SAMPLE_RUST_MINIMAL)		+= rust_minimal.o
+obj-$(CONFIG_SAMPLE_RUST_PRINT)			+= rust_print.o
+obj-$(CONFIG_SAMPLE_RUST_MODULE_PARAMETERS)	+= rust_module_parameters.o
+obj-$(CONFIG_SAMPLE_RUST_SYNC)			+= rust_sync.o
+obj-$(CONFIG_SAMPLE_RUST_CHRDEV)		+= rust_chrdev.o
+obj-$(CONFIG_SAMPLE_RUST_MISCDEV)		+= rust_miscdev.o
+obj-$(CONFIG_SAMPLE_RUST_STACK_PROBING)		+= rust_stack_probing.o
+obj-$(CONFIG_SAMPLE_RUST_SEMAPHORE)		+= rust_semaphore.o
+obj-$(CONFIG_SAMPLE_RUST_SEMAPHORE_C)		+= rust_semaphore_c.o
+obj-$(CONFIG_SAMPLE_RUST_RANDOM)		+= rust_random.o
+obj-$(CONFIG_SAMPLE_RUST_PLATFORM)		+= rust_platform.o

samples/rust/rust_chrdev.rs new file +53 -0

53 lines not on this page · raw message

samples/rust/rust_minimal.rs new file +38 -0

new file mode 100644
index 000000000000..3276dbe8ae94
@@ -0,0 +1,38 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! Rust minimal sample
+
+#![no_std]
+#![feature(allocator_api, global_asm)]
+
+use kernel::prelude::*;
+
+module! {
+    type: RustMinimal,
+    name: b"rust_minimal",
+    author: b"Rust for Linux Contributors",
+    description: b"Rust minimal sample",
+    license: b"GPL v2",
+}
+
+struct RustMinimal {
+    message: String,
+}
+
+impl KernelModule for RustMinimal {
+    fn init(_name: &'static CStr, _module: &'static ThisModule) -> Result<Self> {
+        pr_info!("Rust minimal sample (init)\n");
+        pr_info!("Am I built-in? {}\n", !cfg!(MODULE));
+
+        Ok(RustMinimal {
+            message: "on the heap!".try_to_owned()?,
+        })
+    }
+}
+
+impl Drop for RustMinimal {
+    fn drop(&mut self) {
+        pr_info!("My message is {}\n", self.message);
+        pr_info!("Rust minimal sample (exit)\n");
+    }
+}

samples/rust/rust_miscdev.rs new file +147 -0

147 lines not on this page · raw message

samples/rust/rust_module_parameters.rs new file +72 -0

72 lines not on this page · raw message

samples/rust/rust_platform.rs new file +25 -0

new file mode 100644
index 000000000000..43ff1694a278
@@ -0,0 +1,25 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! Rust platform device driver sample.
+
+#![no_std]
+#![feature(allocator_api, global_asm)]
+
+use kernel::{module_platform_driver, of, platform, prelude::*};
+
+module_platform_driver! {
+    type: Driver,
+    name: b"rust_platform",
+    license: b"GPL v2",
+}
+
+struct Driver;
+impl platform::Driver for Driver {
+    kernel::define_of_id_table! {(), [
+        (of::DeviceId::Compatible(b"rust,sample"), None),
+    ]}
+
+    fn probe(_dev: &mut platform::Device, _id_info: Option<&Self::IdInfo>) -> Result {
+        Ok(())
+    }
+}

samples/rust/rust_print.rs new file +57 -0

57 lines not on this page · raw message

samples/rust/rust_random.rs new file +64 -0

64 lines not on this page · raw message

samples/rust/rust_semaphore.rs new file +175 -0

175 lines not on this page · raw message

samples/rust/rust_semaphore_c.c new file +212 -0

212 lines not on this page · raw message

samples/rust/rust_stack_probing.rs new file +40 -0

new file mode 100644
index 000000000000..4f44fade96aa
@@ -0,0 +1,40 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! Rust stack probing sample
+
+#![no_std]
+#![feature(allocator_api, global_asm)]
+#![feature(bench_black_box)]
+
+use kernel::prelude::*;
+
+module! {
+    type: RustStackProbing,
+    name: b"rust_stack_probing",
+    author: b"Rust for Linux Contributors",
+    description: b"Rust stack probing sample",
+    license: b"GPL v2",
+}
+
+struct RustStackProbing;
+
+impl KernelModule for RustStackProbing {
+    fn init(_name: &'static CStr, _module: &'static ThisModule) -> Result<Self> {
+        pr_info!("Rust stack probing sample (init)\n");
+
+        // Including this large variable on the stack will trigger
+        // stack probing on the supported archs.
+        // This will verify that stack probing does not lead to
+        // any errors if we need to link `__rust_probestack`.
+        let x: [u64; 514] = core::hint::black_box([5; 514]);
+        pr_info!("Large array has length: {}\n", x.len());
+
+        Ok(RustStackProbing)
+    }
+}
+
+impl Drop for RustStackProbing {
+    fn drop(&mut self) {
+        pr_info!("Rust stack probing sample (exit)\n");
+    }
+}

samples/rust/rust_sync.rs new file +81 -0

81 lines not on this page · raw message

Signature · 1 line

2.34.1

Miguel Ojeda

author maintainer

2022-01-17 05:37 UTC #19 lore raw

PATCH v3 17/19 MAINTAINERS: Rust

Miguel, Alex and Wedson will be maintaining the Rust support.

Co-developed-by Alex Gaynor <[email protected]>

Signed-off-by Alex Gaynor <[email protected]>

Co-developed-by Wedson Almeida Filho <[email protected]>

Signed-off-by Wedson Almeida Filho <[email protected]>

---
 MAINTAINERS | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

MAINTAINERS +16 -0

index dd36acc87ce6..5f3816c713fc 100644
@@ -16578,6 +16578,22 @@ L:	[email protected]
 S:	Maintained
 F:	drivers/infiniband/ulp/rtrs/
 
+RUST
+M:	Miguel Ojeda <[email protected]>
+M:	Alex Gaynor <[email protected]>
+M:	Wedson Almeida Filho <[email protected]>
+L:	[email protected]
+S:	Supported
+W:	https://github.com/Rust-for-Linux/linux
+B:	https://github.com/Rust-for-Linux/linux/issues
+T:	git https://github.com/Rust-for-Linux/linux.git rust-next
+F:	rust/
+F:	samples/rust/
+F:	Documentation/rust/
+F:	lib/rust.h
+F:	scripts/*rust*
+K:	\b(?i:rust)\b
+
 RXRPC SOCKETS (AF_RXRPC)
 M:	David Howells <[email protected]>
 M:	Marc Dionne <[email protected]>

Signature · 1 line

2.34.1

Miguel Ojeda

author maintainer

2022-01-17 05:37 UTC #20 lore raw

RFC PATCH v3 18/19 drivers: gpio: PrimeCell PL061 in Rust

From: Wedson Almeida Filho <[email protected]>

A port to Rust of the PrimeCell PL061 GPIO driver.

This module is a work in progress and will be sent for review later on, as well as separately from the Rust support.

However, it is included to show how an actual working module written in Rust may look like.

Signed-off-by Wedson Almeida Filho <[email protected]>

---
 drivers/gpio/Kconfig            |   8 +
 drivers/gpio/Makefile           |   1 +
 drivers/gpio/gpio_pl061_rust.rs | 362 ++++++++++++++++++++++++++++++++
 3 files changed, 371 insertions(+)
 create mode 100644 drivers/gpio/gpio_pl061_rust.rs

drivers/gpio/Kconfig +8 -0

index 60d9374c72c0..8bc208ece49d 100644
@@ -471,6 +471,14 @@ config GPIO_PL061
 	help
 	  Say yes here to support the PrimeCell PL061 GPIO device.
 
+config GPIO_PL061_RUST
+	tristate "PrimeCell PL061 GPIO support written in Rust"
+	depends on ARM_AMBA && RUST
+	select IRQ_DOMAIN
+	select GPIOLIB_IRQCHIP
+	help
+	  Say yes here to support the PrimeCell PL061 GPIO device
+
 config GPIO_PMIC_EIC_SPRD
 	tristate "Spreadtrum PMIC EIC support"
 	depends on MFD_SC27XX_PMIC || COMPILE_TEST

drivers/gpio/Makefile +1 -0

index 71ee9fc2ff83..5021316a5037 100644
@@ -118,6 +118,7 @@ obj-$(CONFIG_GPIO_PCIE_IDIO_24)		+= gpio-pcie-idio-24.o
 obj-$(CONFIG_GPIO_PCI_IDIO_16)		+= gpio-pci-idio-16.o
 obj-$(CONFIG_GPIO_PISOSR)		+= gpio-pisosr.o
 obj-$(CONFIG_GPIO_PL061)		+= gpio-pl061.o
+obj-$(CONFIG_GPIO_PL061_RUST)		+= gpio_pl061_rust.o
 obj-$(CONFIG_GPIO_PMIC_EIC_SPRD)	+= gpio-pmic-eic-sprd.o
 obj-$(CONFIG_GPIO_PXA)			+= gpio-pxa.o
 obj-$(CONFIG_GPIO_RASPBERRYPI_EXP)	+= gpio-raspberrypi-exp.o

drivers/gpio/gpio_pl061_rust.rs new file +362 -0

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Signature · 1 line

2.34.1

Miguel Ojeda

author maintainer

2022-01-17 05:37 UTC #21 lore raw

RFC PATCH v3 19/19 drivers: android: Binder IPC in Rust

From: Wedson Almeida Filho <[email protected]>

A port to Rust of the Android Binder IPC mechanism.

This module is a work in progress and will be sent for review later on, as well as separately from the Rust support.

However, it is included to show how an actual working module written in Rust may look like.

Co-developed-by Alex Gaynor <[email protected]>

Signed-off-by Alex Gaynor <[email protected]>

Co-developed-by Finn Behrens <[email protected]>

Co-developed-by Sven Van Asbroeck <[email protected]>

Signed-off-by Sven Van Asbroeck <[email protected]>

Co-developed-by Gary Guo <[email protected]>

Signed-off-by Gary Guo <[email protected]>

Co-developed-by Wayne Campbell <[email protected]>

Signed-off-by Wayne Campbell <[email protected]>

Signed-off-by Wedson Almeida Filho <[email protected]>

Co-developed-by Miguel Ojeda <[email protected]>