Merge tag 'driver-core-5.10-rc1' of...

Merge tag 'driver-core-5.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core updates from Greg KH:
 "Here is the "big" set of driver core patches for 5.10-rc1

  They include a lot of different things, all related to the driver core
  and/or some driver logic:

   - sysfs common write functions to make it easier to audit sysfs
     attributes

   - device connection cleanups and fixes

   - devm helpers for a few functions

   - NOIO allocations for when devices are being removed

   - minor cleanups and fixes

  All have been in linux-next for a while with no reported issues"

* tag 'driver-core-5.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (31 commits)
  regmap: debugfs: use semicolons rather than commas to separate statements
  platform/x86: intel_pmc_core: do not create a static struct device
  drivers core: node: Use a more typical macro definition style for ACCESS_ATTR
  drivers core: Use sysfs_emit for shared_cpu_map_show and shared_cpu_list_show
  mm: and drivers core: Convert hugetlb_report_node_meminfo to sysfs_emit
  drivers core: Miscellaneous changes for sysfs_emit
  drivers core: Reindent a couple uses around sysfs_emit
  drivers core: Remove strcat uses around sysfs_emit and neaten
  drivers core: Use sysfs_emit and sysfs_emit_at for show(device *...) functions
  sysfs: Add sysfs_emit and sysfs_emit_at to format sysfs output
  dyndbg: use keyword, arg varnames for query term pairs
  driver core: force NOIO allocations during unplug
  platform_device: switch to simpler IDA interface
  driver core: platform: Document return type of more functions
  Revert "driver core: Annotate dev_err_probe() with __must_check"
  Revert "test_firmware: Test platform fw loading on non-EFI systems"
  iio: adc: xilinx-xadc: use devm_krealloc()
  hwmon: pmbus: use more devres helpers
  devres: provide devm_krealloc()
  syscore: Use pm_pr_dbg() for syscore_{suspend,resume}()
  ...

Documentation/driver-api/device_connection.rst

-==================
-Device connections
-==================
-
-Introduction
-------------
-
-Devices often have connections to other devices that are outside of the direct
-child/parent relationship. A serial or network communication controller, which
-could be a PCI device, may need to be able to get a reference to its PHY
-component, which could be attached for example to the I2C bus. Some device
-drivers need to be able to control the clocks or the GPIOs for their devices,
-and so on.
-
-Device connections are generic descriptions of any type of connection between
-two separate devices.
-
-Device connections alone do not create a dependency between the two devices.
-They are only descriptions which are not tied to either of the devices directly.
-A dependency between the two devices exists only if one of the two endpoint
-devices requests a reference to the other. The descriptions themselves can be
-defined in firmware (not yet supported) or they can be built-in.
-
-Usage
------
-
-Device connections should exist before device ``->probe`` callback is called for
-either endpoint device in the description. If the connections are defined in
-firmware, this is not a problem. It should be considered if the connection
-descriptions are "built-in", and need to be added separately.
-
-The connection description consists of the names of the two devices with the
-connection, i.e. the endpoints, and unique identifier for the connection which
-is needed if there are multiple connections between the two devices.
-
-After a description exists, the devices in it can request reference to the other
-endpoint device, or they can request the description itself.
-
-API
----
-
-.. kernel-doc:: drivers/base/devcon.c
-   :functions: device_connection_find_match device_connection_find device_connection_add device_connection_remove

Documentation/driver-api/driver-model/devres.rst

@@ -354,6 +354,7 @@ MEM
   devm_kmalloc()
   devm_kmalloc_array()
   devm_kmemdup()
+  devm_krealloc()
   devm_kstrdup()
   devm_kvasprintf()
   devm_kzalloc()

Documentation/driver-api/firmware/fallback-mechanisms.rst

@@ -42,6 +42,7 @@ fallback mechanism:
   supported for request_firmware_into_buf().
 
 * Firmware is not accessible through typical means:
+
         * It cannot be installed into the root filesystem
         * The firmware provides very unique device specific data tailored for
           the unit gathered with local information. An example is calibration

Documentation/driver-api/index.rst

@@ -22,7 +22,6 @@ available subsections can be seen below.
    pm/index
    clk
    device-io
-   device_connection
    dma-buf
    device_link
    component

Documentation/filesystems/sysfs.rst

@@ -241,12 +241,10 @@ Other notes:
   is 4096.
 
 - show() methods should return the number of bytes printed into the
-  buffer. This is the return value of scnprintf().
+  buffer.
 
-- show() must not use snprintf() when formatting the value to be
-  returned to user space. If you can guarantee that an overflow
-  will never happen you can use sprintf() otherwise you must use
-  scnprintf().
+- show() should only use sysfs_emit() or sysfs_emit_at() when formatting
+  the value to be returned to user space.
 
 - store() should return the number of bytes used from the buffer. If the
   entire buffer has been used, just return the count argument.

MAINTAINERS

@@ -5023,6 +5023,12 @@ S:	Maintained
 F:	drivers/base/devcoredump.c
 F:	include/linux/devcoredump.h
+DEVICE DEPENDENCY HELPER SCRIPT
+M:	Saravana Kannan <saravanak@google.com>
+L:	linux-kernel@vger.kernel.org
+S:	Maintained
+F:	scripts/dev-needs.sh
+
 DEVICE DIRECT ACCESS (DAX)
 M:	Dan Williams <dan.j.williams@intel.com>
 M:	Vishal Verma <vishal.l.verma@intel.com>

drivers/base/Makefile

@@ -6,7 +6,7 @@ obj-y			:= component.o core.o bus.o dd.o syscore.o \
 			   cpu.o firmware.o init.o map.o devres.o \
 			   attribute_container.o transport_class.o \
 			   topology.o container.o property.o cacheinfo.o \
-			   devcon.o swnode.o
+			   swnode.o
 obj-$(CONFIG_DEVTMPFS)	+= devtmpfs.o
 obj-y			+= power/
 obj-$(CONFIG_ISA_BUS_API)	+= isa.o

drivers/base/arch_topology.c

@@ -80,7 +80,7 @@ static ssize_t cpu_capacity_show(struct device *dev,
 {
 	struct cpu *cpu = container_of(dev, struct cpu, dev);
 
-	return sprintf(buf, "%lu\n", topology_get_cpu_scale(cpu->dev.id));
+	return sysfs_emit(buf, "%lu\n", topology_get_cpu_scale(cpu->dev.id));
 }
 
 static void update_topology_flags_workfn(struct work_struct *work);

drivers/base/bus.c

@@ -229,7 +229,7 @@ static DRIVER_ATTR_IGNORE_LOCKDEP(bind, S_IWUSR, NULL, bind_store);
 
 static ssize_t drivers_autoprobe_show(struct bus_type *bus, char *buf)
 {
-	return sprintf(buf, "%d\n", bus->p->drivers_autoprobe);
+	return sysfs_emit(buf, "%d\n", bus->p->drivers_autoprobe);
 }
 
 static ssize_t drivers_autoprobe_store(struct bus_type *bus,

drivers/base/cacheinfo.c

@@ -362,7 +362,7 @@ static ssize_t file_name##_show(struct device *dev,		\
 		struct device_attribute *attr, char *buf)	\
 {								\
 	struct cacheinfo *this_leaf = dev_get_drvdata(dev);	\
-	return sprintf(buf, "%u\n", this_leaf->object);		\
+	return sysfs_emit(buf, "%u\n", this_leaf->object);	\
 }
 
 show_one(id, id);
@@ -377,44 +377,48 @@ static ssize_t size_show(struct device *dev,
 {
 	struct cacheinfo *this_leaf = dev_get_drvdata(dev);
 
-	return sprintf(buf, "%uK\n", this_leaf->size >> 10);
+	return sysfs_emit(buf, "%uK\n", this_leaf->size >> 10);
 }
 
-static ssize_t shared_cpumap_show_func(struct device *dev, bool list, char *buf)
+static ssize_t shared_cpu_map_show(struct device *dev,
+				   struct device_attribute *attr, char *buf)
 {
 	struct cacheinfo *this_leaf = dev_get_drvdata(dev);
 	const struct cpumask *mask = &this_leaf->shared_cpu_map;
 
-	return cpumap_print_to_pagebuf(list, buf, mask);
-}
-
-static ssize_t shared_cpu_map_show(struct device *dev,
-				   struct device_attribute *attr, char *buf)
-{
-	return shared_cpumap_show_func(dev, false, buf);
+	return sysfs_emit(buf, "%*pb\n", nr_cpu_ids, mask);
 }
 
 static ssize_t shared_cpu_list_show(struct device *dev,
 				    struct device_attribute *attr, char *buf)
 {
-	return shared_cpumap_show_func(dev, true, buf);
+	struct cacheinfo *this_leaf = dev_get_drvdata(dev);
+	const struct cpumask *mask = &this_leaf->shared_cpu_map;
+
+	return sysfs_emit(buf, "%*pbl\n", nr_cpu_ids, mask);
 }
 
 static ssize_t type_show(struct device *dev,
 			 struct device_attribute *attr, char *buf)
 {
 	struct cacheinfo *this_leaf = dev_get_drvdata(dev);
+	const char *output;
 
 	switch (this_leaf->type) {
 	case CACHE_TYPE_DATA:
-		return sprintf(buf, "Data\n");
+		output = "Data";
+		break;
 	case CACHE_TYPE_INST:
-		return sprintf(buf, "Instruction\n");
+		output = "Instruction";
+		break;
 	case CACHE_TYPE_UNIFIED:
-		return sprintf(buf, "Unified\n");
+		output = "Unified";
+		break;
 	default:
 		return -EINVAL;
 	}
+
+	return sysfs_emit(buf, "%s\n", output);
 }
 
 static ssize_t allocation_policy_show(struct device *dev,
@@ -422,15 +426,18 @@ static ssize_t allocation_policy_show(struct device *dev,
 {
 	struct cacheinfo *this_leaf = dev_get_drvdata(dev);
 	unsigned int ci_attr = this_leaf->attributes;
-	int n = 0;
+	const char *output;
 
 	if ((ci_attr & CACHE_READ_ALLOCATE) && (ci_attr & CACHE_WRITE_ALLOCATE))
-		n = sprintf(buf, "ReadWriteAllocate\n");
+		output = "ReadWriteAllocate";
 	else if (ci_attr & CACHE_READ_ALLOCATE)
-		n = sprintf(buf, "ReadAllocate\n");
+		output = "ReadAllocate";
 	else if (ci_attr & CACHE_WRITE_ALLOCATE)
-		n = sprintf(buf, "WriteAllocate\n");
-	return n;
+		output = "WriteAllocate";
+	else
+		return 0;
+
+	return sysfs_emit(buf, "%s\n", output);
 }
 
 static ssize_t write_policy_show(struct device *dev,
@@ -441,9 +448,9 @@ static ssize_t write_policy_show(struct device *dev,
 	int n = 0;
 
 	if (ci_attr & CACHE_WRITE_THROUGH)
-		n = sprintf(buf, "WriteThrough\n");
+		n = sysfs_emit(buf, "WriteThrough\n");
 	else if (ci_attr & CACHE_WRITE_BACK)
-		n = sprintf(buf, "WriteBack\n");
+		n = sysfs_emit(buf, "WriteBack\n");
 	return n;
 }
 

drivers/base/class.c

@@ -478,7 +478,7 @@ ssize_t show_class_attr_string(struct class *class,
 	struct class_attribute_string *cs;
 
 	cs = container_of(attr, struct class_attribute_string, attr);
-	return snprintf(buf, PAGE_SIZE, "%s\n", cs->str);
+	return sysfs_emit(buf, "%s\n", cs->str);
 }
 
 EXPORT_SYMBOL_GPL(show_class_attr_string);

drivers/base/core.c

@@ -26,6 +26,7 @@
 #include <linux/pm_runtime.h>
 #include <linux/netdevice.h>
 #include <linux/sched/signal.h>
+#include <linux/sched/mm.h>
 #include <linux/sysfs.h>
 
 #include "base.h"
@@ -239,27 +240,35 @@ void device_pm_move_to_tail(struct device *dev)
 #define to_devlink(dev)	container_of((dev), struct device_link, link_dev)
 
 static ssize_t status_show(struct device *dev,
-			  struct device_attribute *attr, char *buf)
+			   struct device_attribute *attr, char *buf)
 {
-	char *status;
+	const char *output;
 
 	switch (to_devlink(dev)->status) {
 	case DL_STATE_NONE:
-		status = "not tracked"; break;
+		output = "not tracked";
+		break;
 	case DL_STATE_DORMANT:
-		status = "dormant"; break;
+		output = "dormant";
+		break;
 	case DL_STATE_AVAILABLE:
-		status = "available"; break;
+		output = "available";
+		break;
 	case DL_STATE_CONSUMER_PROBE:
-		status = "consumer probing"; break;
+		output = "consumer probing";
+		break;
 	case DL_STATE_ACTIVE:
-		status = "active"; break;
+		output = "active";
+		break;
 	case DL_STATE_SUPPLIER_UNBIND:
-		status = "supplier unbinding"; break;
+		output = "supplier unbinding";
+		break;
 	default:
-		status = "unknown"; break;
+		output = "unknown";
+		break;
 	}
-	return sprintf(buf, "%s\n", status);
+
+	return sysfs_emit(buf, "%s\n", output);
 }
 static DEVICE_ATTR_RO(status);
 
@@ -267,16 +276,16 @@ static ssize_t auto_remove_on_show(struct device *dev,
 				   struct device_attribute *attr, char *buf)
 {
 	struct device_link *link = to_devlink(dev);
-	char *str;
+	const char *output;
 
 	if (link->flags & DL_FLAG_AUTOREMOVE_SUPPLIER)
-		str = "supplier unbind";
+		output = "supplier unbind";
 	else if (link->flags & DL_FLAG_AUTOREMOVE_CONSUMER)
-		str = "consumer unbind";
+		output = "consumer unbind";
 	else
-		str = "never";
+		output = "never";
 
-	return sprintf(buf, "%s\n", str);
+	return sysfs_emit(buf, "%s\n", output);
 }
 static DEVICE_ATTR_RO(auto_remove_on);
 
@@ -285,7 +294,7 @@ static ssize_t runtime_pm_show(struct device *dev,
 {
 	struct device_link *link = to_devlink(dev);
 
-	return sprintf(buf, "%d\n", !!(link->flags & DL_FLAG_PM_RUNTIME));
+	return sysfs_emit(buf, "%d\n", !!(link->flags & DL_FLAG_PM_RUNTIME));
 }
 static DEVICE_ATTR_RO(runtime_pm);
 
@@ -294,7 +303,8 @@ static ssize_t sync_state_only_show(struct device *dev,
 {
 	struct device_link *link = to_devlink(dev);
 
-	return sprintf(buf, "%d\n", !!(link->flags & DL_FLAG_SYNC_STATE_ONLY));
+	return sysfs_emit(buf, "%d\n",
+			  !!(link->flags & DL_FLAG_SYNC_STATE_ONLY));
 }
 static DEVICE_ATTR_RO(sync_state_only);
 
@@ -1059,7 +1069,7 @@ static ssize_t waiting_for_supplier_show(struct device *dev,
 	      && dev->links.need_for_probe;
 	mutex_unlock(&wfs_lock);
 	device_unlock(dev);
-	return sprintf(buf, "%u\n", val);
+	return sysfs_emit(buf, "%u\n", val);
 }
 static DEVICE_ATTR_RO(waiting_for_supplier);
 
@@ -1709,7 +1719,7 @@ ssize_t device_show_ulong(struct device *dev,
 			  char *buf)
 {
 	struct dev_ext_attribute *ea = to_ext_attr(attr);
-	return snprintf(buf, PAGE_SIZE, "%lx\n", *(unsigned long *)(ea->var));
+	return sysfs_emit(buf, "%lx\n", *(unsigned long *)(ea->var));
 }
 EXPORT_SYMBOL_GPL(device_show_ulong);
 
@@ -1739,7 +1749,7 @@ ssize_t device_show_int(struct device *dev,
 {
 	struct dev_ext_attribute *ea = to_ext_attr(attr);
 
-	return snprintf(buf, PAGE_SIZE, "%d\n", *(int *)(ea->var));
+	return sysfs_emit(buf, "%d\n", *(int *)(ea->var));
 }
 EXPORT_SYMBOL_GPL(device_show_int);
 
@@ -1760,7 +1770,7 @@ ssize_t device_show_bool(struct device *dev, struct device_attribute *attr,
 {
 	struct dev_ext_attribute *ea = to_ext_attr(attr);
 
-	return snprintf(buf, PAGE_SIZE, "%d\n", *(bool *)(ea->var));
+	return sysfs_emit(buf, "%d\n", *(bool *)(ea->var));
 }
 EXPORT_SYMBOL_GPL(device_show_bool);
 
@@ -1932,7 +1942,7 @@ static ssize_t uevent_show(struct device *dev, struct device_attribute *attr,
 	struct kset *kset;
 	struct kobj_uevent_env *env = NULL;
 	int i;
-	size_t count = 0;
+	int len = 0;
 	int retval;
 
 	/* search the kset, the device belongs to */
@@ -1962,10 +1972,10 @@ static ssize_t uevent_show(struct device *dev, struct device_attribute *attr,
 
 	/* copy keys to file */
 	for (i = 0; i < env->envp_idx; i++)
-		count += sprintf(&buf[count], "%s\n", env->envp[i]);
+		len += sysfs_emit_at(buf, len, "%s\n", env->envp[i]);
 out:
 	kfree(env);
-	return count;
+	return len;
 }
 
 static ssize_t uevent_store(struct device *dev, struct device_attribute *attr,
@@ -1992,7 +2002,7 @@ static ssize_t online_show(struct device *dev, struct device_attribute *attr,
 	device_lock(dev);
 	val = !dev->offline;
 	device_unlock(dev);
-	return sprintf(buf, "%u\n", val);
+	return sysfs_emit(buf, "%u\n", val);
 }
 
 static ssize_t online_store(struct device *dev, struct device_attribute *attr,
@@ -3062,6 +3072,7 @@ void device_del(struct device *dev)
 	struct device *parent = dev->parent;
 	struct kobject *glue_dir = NULL;
 	struct class_interface *class_intf;
+	unsigned int noio_flag;
 
 	device_lock(dev);
 	kill_device(dev);
@@ -3073,6 +3084,7 @@ void device_del(struct device *dev)
 	/* Notify clients of device removal.  This call must come
 	 * before dpm_sysfs_remove().
 	 */
+	noio_flag = memalloc_noio_save();
 	if (dev->bus)
 		blocking_notifier_call_chain(&dev->bus->p->bus_notifier,
 					     BUS_NOTIFY_DEL_DEVICE, dev);
@@ -3114,6 +3126,7 @@ void device_del(struct device *dev)
 	glue_dir = get_glue_dir(dev);
 	kobject_del(&dev->kobj);
 	cleanup_glue_dir(dev, glue_dir);
+	memalloc_noio_restore(noio_flag);
 	put_device(parent);
 }
 EXPORT_SYMBOL_GPL(device_del);

drivers/base/cpu.c

@@ -139,11 +139,11 @@ EXPORT_SYMBOL_GPL(cpu_subsys);
 #ifdef CONFIG_KEXEC
 #include <linux/kexec.h>
 
-static ssize_t show_crash_notes(struct device *dev, struct device_attribute *attr,
+static ssize_t crash_notes_show(struct device *dev,
+				struct device_attribute *attr,
 				char *buf)
 {
 	struct cpu *cpu = container_of(dev, struct cpu, dev);
-	ssize_t rc;
 	unsigned long long addr;
 	int cpunum;
 
@@ -156,21 +156,18 @@ static ssize_t show_crash_notes(struct device *dev, struct device_attribute *att
 	 * operation should be safe. No locking required.
 	 */
 	addr = per_cpu_ptr_to_phys(per_cpu_ptr(crash_notes, cpunum));
-	rc = sprintf(buf, "%Lx\n", addr);
-	return rc;
+
+	return sysfs_emit(buf, "%llx\n", addr);
 }
-static DEVICE_ATTR(crash_notes, 0400, show_crash_notes, NULL);
+static DEVICE_ATTR_ADMIN_RO(crash_notes);
 
-static ssize_t show_crash_notes_size(struct device *dev,
+static ssize_t crash_notes_size_show(struct device *dev,
 				     struct device_attribute *attr,
 				     char *buf)
 {
-	ssize_t rc;
-
-	rc = sprintf(buf, "%zu\n", sizeof(note_buf_t));
-	return rc;
+	return sysfs_emit(buf, "%zu\n", sizeof(note_buf_t));
 }
-static DEVICE_ATTR(crash_notes_size, 0400, show_crash_notes_size, NULL);
+static DEVICE_ATTR_ADMIN_RO(crash_notes_size);
 
 static struct attribute *crash_note_cpu_attrs[] = {
 	&dev_attr_crash_notes.attr,
@@ -231,7 +228,7 @@ static struct cpu_attr cpu_attrs[] = {
 static ssize_t print_cpus_kernel_max(struct device *dev,
 				     struct device_attribute *attr, char *buf)
 {
-	return sprintf(buf, "%d\n", NR_CPUS - 1);
+	return sysfs_emit(buf, "%d\n", NR_CPUS - 1);
 }
 static DEVICE_ATTR(kernel_max, 0444, print_cpus_kernel_max, NULL);
 
@@ -241,37 +238,37 @@ unsigned int total_cpus;
 static ssize_t print_cpus_offline(struct device *dev,
 				  struct device_attribute *attr, char *buf)
 {
-	int n = 0, len = PAGE_SIZE-2;
+	int len = 0;
 	cpumask_var_t offline;
 
 	/* display offline cpus < nr_cpu_ids */
 	if (!alloc_cpumask_var(&offline, GFP_KERNEL))
 		return -ENOMEM;
 	cpumask_andnot(offline, cpu_possible_mask, cpu_online_mask);
-	n = scnprintf(buf, len, "%*pbl", cpumask_pr_args(offline));
+	len += sysfs_emit_at(buf, len, "%*pbl", cpumask_pr_args(offline));
 	free_cpumask_var(offline);
 
 	/* display offline cpus >= nr_cpu_ids */
 	if (total_cpus && nr_cpu_ids < total_cpus) {
-		if (n && n < len)
-			buf[n++] = ',';
+		len += sysfs_emit_at(buf, len, ",");
 
 		if (nr_cpu_ids == total_cpus-1)
-			n += scnprintf(&buf[n], len - n, "%u", nr_cpu_ids);
+			len += sysfs_emit_at(buf, len, "%u", nr_cpu_ids);
 		else
-			n += scnprintf(&buf[n], len - n, "%u-%d",
-						      nr_cpu_ids, total_cpus-1);
+			len += sysfs_emit_at(buf, len, "%u-%d",
+					     nr_cpu_ids, total_cpus - 1);
 	}
 
-	n += scnprintf(&buf[n], len - n, "\n");
-	return n;
+	len += sysfs_emit_at(buf, len, "\n");
+
+	return len;
 }
 static DEVICE_ATTR(offline, 0444, print_cpus_offline, NULL);
 
 static ssize_t print_cpus_isolated(struct device *dev,
 				  struct device_attribute *attr, char *buf)
 {
-	int n;
+	int len;
 	cpumask_var_t isolated;
 
 	if (!alloc_cpumask_var(&isolated, GFP_KERNEL))
@@ -279,19 +276,19 @@ static ssize_t print_cpus_isolated(struct device *dev,
 
 	cpumask_andnot(isolated, cpu_possible_mask,
 		       housekeeping_cpumask(HK_FLAG_DOMAIN));
-	n = sprintf(buf, "%*pbl\n", cpumask_pr_args(isolated));
+	len = sysfs_emit(buf, "%*pbl\n", cpumask_pr_args(isolated));
 
 	free_cpumask_var(isolated);
 
-	return n;
+	return len;
 }
 static DEVICE_ATTR(isolated, 0444, print_cpus_isolated, NULL);
 
 #ifdef CONFIG_NO_HZ_FULL
 static ssize_t print_cpus_nohz_full(struct device *dev,
-				  struct device_attribute *attr, char *buf)
+				    struct device_attribute *attr, char *buf)
 {
-	return sprintf(buf, "%*pbl\n", cpumask_pr_args(tick_nohz_full_mask));
+	return sysfs_emit(buf, "%*pbl\n", cpumask_pr_args(tick_nohz_full_mask));
 }
 static DEVICE_ATTR(nohz_full, 0444, print_cpus_nohz_full, NULL);
 #endif
@@ -320,22 +317,23 @@ static ssize_t print_cpu_modalias(struct device *dev,
 				  struct device_attribute *attr,
 				  char *buf)
 {
-	ssize_t n;
+	int len = 0;
 	u32 i;
 
-	n = sprintf(buf, "cpu:type:" CPU_FEATURE_TYPEFMT ":feature:",
-		    CPU_FEATURE_TYPEVAL);
+	len += sysfs_emit_at(buf, len,
+			     "cpu:type:" CPU_FEATURE_TYPEFMT ":feature:",
+			     CPU_FEATURE_TYPEVAL);
 
 	for (i = 0; i < MAX_CPU_FEATURES; i++)
 		if (cpu_have_feature(i)) {
-			if (PAGE_SIZE < n + sizeof(",XXXX\n")) {
+			if (len + sizeof(",XXXX\n") >= PAGE_SIZE) {
 				WARN(1, "CPU features overflow page\n");
 				break;
 			}
-			n += sprintf(&buf[n], ",%04X", i);
+			len += sysfs_emit_at(buf, len, ",%04X", i);
 		}
-	buf[n++] = '\n';
-	return n;
+	len += sysfs_emit_at(buf, len, "\n");
+	return len;
 }
 
 static int cpu_uevent(struct device *dev, struct kobj_uevent_env *env)
@@ -516,56 +514,56 @@ static void __init cpu_dev_register_generic(void)
 ssize_t __weak cpu_show_meltdown(struct device *dev,
 				 struct device_attribute *attr, char *buf)
 {
-	return sprintf(buf, "Not affected\n");
+	return sysfs_emit(buf, "Not affected\n");
 }
 
 ssize_t __weak cpu_show_spectre_v1(struct device *dev,
 				   struct device_attribute *attr, char *buf)
 {
-	return sprintf(buf, "Not affected\n");
+	return sysfs_emit(buf, "Not affected\n");
 }
 
 ssize_t __weak cpu_show_spectre_v2(struct device *dev,
 				   struct device_attribute *attr, char *buf)
 {
-	return sprintf(buf, "Not affected\n");
+	return sysfs_emit(buf, "Not affected\n");
 }
 
 ssize_t __weak cpu_show_spec_store_bypass(struct device *dev,
 					  struct device_attribute *attr, char *buf)
 {
-	return sprintf(buf, "Not affected\n");
+	return sysfs_emit(buf, "Not affected\n");
 }
 
 ssize_t __weak cpu_show_l1tf(struct device *dev,
 			     struct device_attribute *attr, char *buf)
 {
-	return sprintf(buf, "Not affected\n");
+	return sysfs_emit(buf, "Not affected\n");
 }
 
 ssize_t __weak cpu_show_mds(struct device *dev,
 			    struct device_attribute *attr, char *buf)
 {
-	return sprintf(buf, "Not affected\n");
+	return sysfs_emit(buf, "Not affected\n");
 }
 
 ssize_t __weak cpu_show_tsx_async_abort(struct device *dev,
 					struct device_attribute *attr,
 					char *buf)
 {
-	return sprintf(buf, "Not affected\n");
+	return sysfs_emit(buf, "Not affected\n");
 }
 
 ssize_t __weak cpu_show_itlb_multihit(struct device *dev,
-			    struct device_attribute *attr, char *buf)
+				      struct device_attribute *attr, char *buf)
 {
-	return sprintf(buf, "Not affected\n");
+	return sysfs_emit(buf, "Not affected\n");
 }
 
 ssize_t __weak cpu_show_srbds(struct device *dev,
 			      struct device_attribute *attr, char *buf)
 {
-	return sprintf(buf, "Not affected\n");
+	return sysfs_emit(buf, "Not affected\n");
 }
 
 static DEVICE_ATTR(meltdown, 0444, cpu_show_meltdown, NULL);

drivers/base/dd.c

@@ -486,7 +486,8 @@ static ssize_t state_synced_show(struct device *dev,
 	device_lock(dev);
 	val = dev->state_synced;
 	device_unlock(dev);
-	return sprintf(buf, "%u\n", val);
+
+	return sysfs_emit(buf, "%u\n", val);
 }
 static DEVICE_ATTR_RO(state_synced);
 
@@ -658,15 +659,14 @@ static int really_probe(struct device *dev, struct device_driver *drv)
  */
 static int really_probe_debug(struct device *dev, struct device_driver *drv)
 {
-	ktime_t calltime, delta, rettime;
+	ktime_t calltime, rettime;
 	int ret;
 
 	calltime = ktime_get();
 	ret = really_probe(dev, drv);
 	rettime = ktime_get();
-	delta = ktime_sub(rettime, calltime);
 	pr_debug("probe of %s returned %d after %lld usecs\n",
-		 dev_name(dev), ret, (s64) ktime_to_us(delta));
+		 dev_name(dev), ret, ktime_us_delta(rettime, calltime));
 	return ret;
 }
 

drivers/base/devcon.c

-// SPDX-License-Identifier: GPL-2.0
-/**
- * Device connections
- *
- * Copyright (C) 2018 Intel Corporation
- * Author: Heikki Krogerus <heikki.krogerus@linux.intel.com>
- */
-
-#include <linux/device.h>
-#include <linux/property.h>
-
-static DEFINE_MUTEX(devcon_lock);
-static LIST_HEAD(devcon_list);
-
-static void *
-fwnode_graph_devcon_match(struct fwnode_handle *fwnode, const char *con_id,
-			  void *data, devcon_match_fn_t match)
-{
-	struct device_connection con = { .id = con_id };
-	struct fwnode_handle *ep;
-	void *ret;
-
-	fwnode_graph_for_each_endpoint(fwnode, ep) {
-		con.fwnode = fwnode_graph_get_remote_port_parent(ep);
-		if (!fwnode_device_is_available(con.fwnode))
-			continue;
-
-		ret = match(&con, -1, data);
-		fwnode_handle_put(con.fwnode);
-		if (ret) {
-			fwnode_handle_put(ep);
-			return ret;
-		}
-	}
-	return NULL;
-}
-
-static void *
-fwnode_devcon_match(struct fwnode_handle *fwnode, const char *con_id,
-		    void *data, devcon_match_fn_t match)
-{
-	struct device_connection con = { };
-	void *ret;
-	int i;
-
-	for (i = 0; ; i++) {
-		con.fwnode = fwnode_find_reference(fwnode, con_id, i);
-		if (IS_ERR(con.fwnode))
-			break;
-
-		ret = match(&con, -1, data);
-		fwnode_handle_put(con.fwnode);
-		if (ret)
-			return ret;
-	}
-
-	return NULL;
-}
-
-/**
- * fwnode_connection_find_match - Find connection from a device node
- * @fwnode: Device node with the connection
- * @con_id: Identifier for the connection
- * @data: Data for the match function
- * @match: Function to check and convert the connection description
- *
- * Find a connection with unique identifier @con_id between @fwnode and another
- * device node. @match will be used to convert the connection description to
- * data the caller is expecting to be returned.
- */
-void *fwnode_connection_find_match(struct fwnode_handle *fwnode,
-				   const char *con_id, void *data,
-				   devcon_match_fn_t match)
-{
-	void *ret;
-
-	if (!fwnode || !match)
-		return NULL;
-
-	ret = fwnode_graph_devcon_match(fwnode, con_id, data, match);
-	if (ret)
-		return ret;
-
-	return fwnode_devcon_match(fwnode, con_id, data, match);
-}
-EXPORT_SYMBOL_GPL(fwnode_connection_find_match);
-
-/**
- * device_connection_find_match - Find physical connection to a device
- * @dev: Device with the connection
- * @con_id: Identifier for the connection
- * @data: Data for the match function
- * @match: Function to check and convert the connection description
- *
- * Find a connection with unique identifier @con_id between @dev and another
- * device. @match will be used to convert the connection description to data the
- * caller is expecting to be returned.
- */
-void *device_connection_find_match(struct device *dev, const char *con_id,
-				   void *data, devcon_match_fn_t match)
-{
-	struct fwnode_handle *fwnode = dev_fwnode(dev);
-	const char *devname = dev_name(dev);
-	struct device_connection *con;
-	void *ret = NULL;
-	int ep;
-
-	if (!match)
-		return NULL;
-
-	ret = fwnode_connection_find_match(fwnode, con_id, data, match);
-	if (ret)
-		return ret;
-
-	mutex_lock(&devcon_lock);
-
-	list_for_each_entry(con, &devcon_list, list) {
-		ep = match_string(con->endpoint, 2, devname);
-		if (ep < 0)
-			continue;
-
-		if (con_id && strcmp(con->id, con_id))
-			continue;
-
-		ret = match(con, !ep, data);
-		if (ret)
-			break;
-	}
-
-	mutex_unlock(&devcon_lock);
-
-	return ret;
-}
-EXPORT_SYMBOL_GPL(device_connection_find_match);
-
-extern struct bus_type platform_bus_type;
-extern struct bus_type pci_bus_type;
-extern struct bus_type i2c_bus_type;
-extern struct bus_type spi_bus_type;
-
-static struct bus_type *generic_match_buses[] = {
-	&platform_bus_type,
-#ifdef CONFIG_PCI
-	&pci_bus_type,
-#endif
-#ifdef CONFIG_I2C
-	&i2c_bus_type,
-#endif
-#ifdef CONFIG_SPI_MASTER
-	&spi_bus_type,
-#endif
-	NULL,
-};
-
-static void *device_connection_fwnode_match(struct device_connection *con)
-{
-	struct bus_type *bus;
-	struct device *dev;
-
-	for (bus = generic_match_buses[0]; bus; bus++) {
-		dev = bus_find_device_by_fwnode(bus, con->fwnode);
-		if (dev && !strncmp(dev_name(dev), con->id, strlen(con->id)))
-			return dev;
-
-		put_device(dev);
-	}
-	return NULL;
-}
-
-/* This tries to find the device from the most common bus types by name. */
-static void *generic_match(struct device_connection *con, int ep, void *data)
-{
-	struct bus_type *bus;
-	struct device *dev;
-
-	if (con->fwnode)
-		return device_connection_fwnode_match(con);
-
-	for (bus = generic_match_buses[0]; bus; bus++) {
-		dev = bus_find_device_by_name(bus, NULL, con->endpoint[ep]);
-		if (dev)
-			return dev;
-	}
-
-	/*
-	 * We only get called if a connection was found, tell the caller to
-	 * wait for the other device to show up.
-	 */
-	return ERR_PTR(-EPROBE_DEFER);
-}
-
-/**
- * device_connection_find - Find two devices connected together
- * @dev: Device with the connection
- * @con_id: Identifier for the connection
- *
- * Find a connection with unique identifier @con_id between @dev and
- * another device. On success returns handle to the device that is connected
- * to @dev, with the reference count for the found device incremented. Returns
- * NULL if no matching connection was found, or ERR_PTR(-EPROBE_DEFER) when a
- * connection was found but the other device has not been enumerated yet.
- */
-struct device *device_connection_find(struct device *dev, const char *con_id)
-{
-	return device_connection_find_match(dev, con_id, NULL, generic_match);
-}
-EXPORT_SYMBOL_GPL(device_connection_find);
-
-/**
- * device_connection_add - Register a connection description
- * @con: The connection description to be registered
- */
-void device_connection_add(struct device_connection *con)
-{
-	mutex_lock(&devcon_lock);
-	list_add_tail(&con->list, &devcon_list);
-	mutex_unlock(&devcon_lock);
-}
-EXPORT_SYMBOL_GPL(device_connection_add);
-
-/**
- * device_connections_remove - Unregister connection description
- * @con: The connection description to be unregistered
- */
-void device_connection_remove(struct device_connection *con)
-{
-	mutex_lock(&devcon_lock);
-	list_del(&con->list);
-	mutex_unlock(&devcon_lock);
-}
-EXPORT_SYMBOL_GPL(device_connection_remove);

drivers/base/devcoredump.c

@@ -123,7 +123,7 @@ static int devcd_free(struct device *dev, void *data)
 static ssize_t disabled_show(struct class *class, struct class_attribute *attr,
 			     char *buf)
 {
-	return sprintf(buf, "%d\n", devcd_disabled);
+	return sysfs_emit(buf, "%d\n", devcd_disabled);
 }
 
 static ssize_t disabled_store(struct class *class, struct class_attribute *attr,

drivers/base/devres.c

@@ -126,6 +126,14 @@ static void add_dr(struct device *dev, struct devres_node *node)
 	list_add_tail(&node->entry, &dev->devres_head);
 }
 
+static void replace_dr(struct device *dev,
+		       struct devres_node *old, struct devres_node *new)
+{
+	devres_log(dev, old, "REPLACE");
+	BUG_ON(!list_empty(&new->entry));
+	list_replace(&old->entry, &new->entry);
+}
+
 #ifdef CONFIG_DEBUG_DEVRES
 void * __devres_alloc_node(dr_release_t release, size_t size, gfp_t gfp, int nid,
 		      const char *name)
@@ -837,6 +845,103 @@ void *devm_kmalloc(struct device *dev, size_t size, gfp_t gfp)
 }
 EXPORT_SYMBOL_GPL(devm_kmalloc);
 
+/**
+ * devm_krealloc - Resource-managed krealloc()
+ * @dev: Device to re-allocate memory for
+ * @ptr: Pointer to the memory chunk to re-allocate
+ * @new_size: New allocation size
+ * @gfp: Allocation gfp flags
+ *
+ * Managed krealloc(). Resizes the memory chunk allocated with devm_kmalloc().
+ * Behaves similarly to regular krealloc(): if @ptr is NULL or ZERO_SIZE_PTR,
+ * it's the equivalent of devm_kmalloc(). If new_size is zero, it frees the
+ * previously allocated memory and returns ZERO_SIZE_PTR. This function doesn't
+ * change the order in which the release callback for the re-alloc'ed devres
+ * will be called (except when falling back to devm_kmalloc() or when freeing
+ * resources when new_size is zero). The contents of the memory are preserved
+ * up to the lesser of new and old sizes.
+ */
+void *devm_krealloc(struct device *dev, void *ptr, size_t new_size, gfp_t gfp)
+{
+	size_t total_new_size, total_old_size;
+	struct devres *old_dr, *new_dr;
+	unsigned long flags;
+
+	if (unlikely(!new_size)) {
+		devm_kfree(dev, ptr);
+		return ZERO_SIZE_PTR;
+	}
+
+	if (unlikely(ZERO_OR_NULL_PTR(ptr)))
+		return devm_kmalloc(dev, new_size, gfp);
+
+	if (WARN_ON(is_kernel_rodata((unsigned long)ptr)))
+		/*
+		 * We cannot reliably realloc a const string returned by
+		 * devm_kstrdup_const().
+		 */
+		return NULL;
+
+	if (!check_dr_size(new_size, &total_new_size))
+		return NULL;
+
+	total_old_size = ksize(container_of(ptr, struct devres, data));
+	if (total_old_size == 0) {
+		WARN(1, "Pointer doesn't point to dynamically allocated memory.");
+		return NULL;
+	}
+
+	/*
+	 * If new size is smaller or equal to the actual number of bytes
+	 * allocated previously - just return the same pointer.
+	 */
+	if (total_new_size <= total_old_size)
+		return ptr;
+
+	/*
+	 * Otherwise: allocate new, larger chunk. We need to allocate before
+	 * taking the lock as most probably the caller uses GFP_KERNEL.
+	 */
+	new_dr = alloc_dr(devm_kmalloc_release,
+			  total_new_size, gfp, dev_to_node(dev));
+	if (!new_dr)
+		return NULL;
+
+	/*
+	 * The spinlock protects the linked list against concurrent
+	 * modifications but not the resource itself.
+	 */
+	spin_lock_irqsave(&dev->devres_lock, flags);
+
+	old_dr = find_dr(dev, devm_kmalloc_release, devm_kmalloc_match, ptr);
+	if (!old_dr) {
+		spin_unlock_irqrestore(&dev->devres_lock, flags);
+		kfree(new_dr);
+		WARN(1, "Memory chunk not managed or managed by a different device.");
+		return NULL;
+	}
+
+	replace_dr(dev, &old_dr->node, &new_dr->node);
+
+	spin_unlock_irqrestore(&dev->devres_lock, flags);
+
+	/*
+	 * We can copy the memory contents after releasing the lock as we're
+	 * no longer modyfing the list links.
+	 */
+	memcpy(new_dr->data, old_dr->data,
+	       total_old_size - offsetof(struct devres, data));
+	/*
+	 * Same for releasing the old devres - it's now been removed from the
+	 * list. This is also the reason why we must not use devm_kfree() - the
+	 * links are no longer valid.
+	 */
+	kfree(old_dr);
+
+	return new_dr->data;
+}
+EXPORT_SYMBOL_GPL(devm_krealloc);
+
 /**
  * devm_kstrdup - Allocate resource managed space and
  *                copy an existing string into that.

drivers/base/firmware_loader/fallback.c

@@ -124,7 +124,7 @@ void kill_pending_fw_fallback_reqs(bool only_kill_custom)
 static ssize_t timeout_show(struct class *class, struct class_attribute *attr,
 			    char *buf)
 {
-	return sprintf(buf, "%d\n", __firmware_loading_timeout());
+	return sysfs_emit(buf, "%d\n", __firmware_loading_timeout());
 }
 
 /**
@@ -219,7 +219,7 @@ static ssize_t firmware_loading_show(struct device *dev,
 		loading = fw_sysfs_loading(fw_sysfs->fw_priv);
 	mutex_unlock(&fw_lock);
 
-	return sprintf(buf, "%d\n", loading);
+	return sysfs_emit(buf, "%d\n", loading);
 }
 
 /**

drivers/base/memory.c

@@ -119,7 +119,8 @@ static ssize_t phys_index_show(struct device *dev,
 	unsigned long phys_index;
 
 	phys_index = mem->start_section_nr / sections_per_block;
-	return sprintf(buf, "%08lx\n", phys_index);
+
+	return sysfs_emit(buf, "%08lx\n", phys_index);
 }
 
 /*
@@ -129,7 +130,7 @@ static ssize_t phys_index_show(struct device *dev,
 static ssize_t removable_show(struct device *dev, struct device_attribute *attr,
 			      char *buf)
 {
-	return sprintf(buf, "%d\n", (int)IS_ENABLED(CONFIG_MEMORY_HOTREMOVE));
+	return sysfs_emit(buf, "%d\n", (int)IS_ENABLED(CONFIG_MEMORY_HOTREMOVE));
 }
 
 /*
@@ -139,7 +140,7 @@ static ssize_t state_show(struct device *dev, struct device_attribute *attr,
 			  char *buf)
 {
 	struct memory_block *mem = to_memory_block(dev);
-	ssize_t len = 0;
+	const char *output;
 
 	/*
 	 * We can probably put these states in a nice little array
@@ -147,22 +148,20 @@ static ssize_t state_show(struct device *dev, struct device_attribute *attr,
 	 */
 	switch (mem->state) {
 	case MEM_ONLINE:
-		len = sprintf(buf, "online\n");
+		output = "online";
 		break;
 	case MEM_OFFLINE:
-		len = sprintf(buf, "offline\n");
+		output = "offline";
 		break;
 	case MEM_GOING_OFFLINE:
-		len = sprintf(buf, "going-offline\n");
+		output = "going-offline";
 		break;
 	default:
-		len = sprintf(buf, "ERROR-UNKNOWN-%ld\n",
-				mem->state);
 		WARN_ON(1);
-		break;
+		return sysfs_emit(buf, "ERROR-UNKNOWN-%ld\n", mem->state);
 	}
 
-	return len;
+	return sysfs_emit(buf, "%s\n", output);
 }
 
 int memory_notify(unsigned long val, void *v)
@@ -303,21 +302,22 @@ static ssize_t phys_device_show(struct device *dev,
 				struct device_attribute *attr, char *buf)
 {
 	struct memory_block *mem = to_memory_block(dev);
-	return sprintf(buf, "%d\n", mem->phys_device);
+
+	return sysfs_emit(buf, "%d\n", mem->phys_device);
 }
 
 #ifdef CONFIG_MEMORY_HOTREMOVE
-static void print_allowed_zone(char *buf, int nid, unsigned long start_pfn,
-		unsigned long nr_pages, int online_type,
-		struct zone *default_zone)
+static int print_allowed_zone(char *buf, int len, int nid,
+			      unsigned long start_pfn, unsigned long nr_pages,
+			      int online_type, struct zone *default_zone)
 {
 	struct zone *zone;
 
 	zone = zone_for_pfn_range(online_type, nid, start_pfn, nr_pages);
-	if (zone != default_zone) {
-		strcat(buf, " ");
-		strcat(buf, zone->name);
-	}
+	if (zone == default_zone)
+		return 0;
+
+	return sysfs_emit_at(buf, len, " %s", zone->name);
 }
 
 static ssize_t valid_zones_show(struct device *dev,
@@ -327,6 +327,7 @@ static ssize_t valid_zones_show(struct device *dev,
 	unsigned long start_pfn = section_nr_to_pfn(mem->start_section_nr);
 	unsigned long nr_pages = PAGES_PER_SECTION * sections_per_block;
 	struct zone *default_zone;
+	int len = 0;
 	int nid;
 
 	/*
@@ -341,24 +342,23 @@ static ssize_t valid_zones_show(struct device *dev,
 		default_zone = test_pages_in_a_zone(start_pfn,
 						    start_pfn + nr_pages);
 		if (!default_zone)
-			return sprintf(buf, "none\n");
-		strcat(buf, default_zone->name);
+			return sysfs_emit(buf, "%s\n", "none");
+		len += sysfs_emit_at(buf, len, "%s", default_zone->name);
 		goto out;
 	}
 
 	nid = mem->nid;
 	default_zone = zone_for_pfn_range(MMOP_ONLINE, nid, start_pfn,
 					  nr_pages);
-	strcat(buf, default_zone->name);
 
-	print_allowed_zone(buf, nid, start_pfn, nr_pages, MMOP_ONLINE_KERNEL,
-			default_zone);
-	print_allowed_zone(buf, nid, start_pfn, nr_pages, MMOP_ONLINE_MOVABLE,
-			default_zone);
+	len += sysfs_emit_at(buf, len, "%s", default_zone->name);
+	len += print_allowed_zone(buf, len, nid, start_pfn, nr_pages,
+				  MMOP_ONLINE_KERNEL, default_zone);
+	len += print_allowed_zone(buf, len, nid, start_pfn, nr_pages,
+				  MMOP_ONLINE_MOVABLE, default_zone);
 out:
-	strcat(buf, "\n");
-
-	return strlen(buf);
+	len += sysfs_emit_at(buf, len, "\n");
+	return len;
 }
 static DEVICE_ATTR_RO(valid_zones);
 #endif
@@ -374,7 +374,7 @@ static DEVICE_ATTR_RO(removable);
 static ssize_t block_size_bytes_show(struct device *dev,
 				     struct device_attribute *attr, char *buf)
 {
-	return sprintf(buf, "%lx\n", memory_block_size_bytes());
+	return sysfs_emit(buf, "%lx\n", memory_block_size_bytes());
 }
 
 static DEVICE_ATTR_RO(block_size_bytes);
@@ -386,8 +386,8 @@ static DEVICE_ATTR_RO(block_size_bytes);
 static ssize_t auto_online_blocks_show(struct device *dev,
 				       struct device_attribute *attr, char *buf)
 {
-	return sprintf(buf, "%s\n",
-		       online_type_to_str[memhp_default_online_type]);
+	return sysfs_emit(buf, "%s\n",
+			  online_type_to_str[memhp_default_online_type]);
 }
 
 static ssize_t auto_online_blocks_store(struct device *dev,

drivers/base/node.c

@@ -46,19 +46,23 @@ static ssize_t node_read_cpumap(struct device *dev, bool list, char *buf)
 	return n;
 }
 
-static inline ssize_t node_read_cpumask(struct device *dev,
-				struct device_attribute *attr, char *buf)
+static inline ssize_t cpumap_show(struct device *dev,
+				  struct device_attribute *attr,
+				  char *buf)
 {
 	return node_read_cpumap(dev, false, buf);
 }
-static inline ssize_t node_read_cpulist(struct device *dev,
-				struct device_attribute *attr, char *buf)
+
+static DEVICE_ATTR_RO(cpumap);
+
+static inline ssize_t cpulist_show(struct device *dev,
+				   struct device_attribute *attr,
+				   char *buf)
 {
 	return node_read_cpumap(dev, true, buf);
 }
 
-static DEVICE_ATTR(cpumap,  S_IRUGO, node_read_cpumask, NULL);
-static DEVICE_ATTR(cpulist, S_IRUGO, node_read_cpulist, NULL);
+static DEVICE_ATTR_RO(cpulist);
 
 /**
  * struct node_access_nodes - Access class device to hold user visible
@@ -153,19 +157,20 @@ static struct node_access_nodes *node_init_node_access(struct node *node,
 }
 
 #ifdef CONFIG_HMEM_REPORTING
-#define ACCESS_ATTR(name) 						   \
-static ssize_t name##_show(struct device *dev,				   \
-			   struct device_attribute *attr,		   \
-			   char *buf)					   \
-{									   \
-	return sprintf(buf, "%u\n", to_access_nodes(dev)->hmem_attrs.name); \
-}									   \
-static DEVICE_ATTR_RO(name);
-
-ACCESS_ATTR(read_bandwidth)
-ACCESS_ATTR(read_latency)
-ACCESS_ATTR(write_bandwidth)
-ACCESS_ATTR(write_latency)
+#define ACCESS_ATTR(name)						\
+static ssize_t name##_show(struct device *dev,				\
+			   struct device_attribute *attr,		\
+			   char *buf)					\
+{									\
+	return sysfs_emit(buf, "%u\n",					\
+			  to_access_nodes(dev)->hmem_attrs.name);	\
+}									\
+static DEVICE_ATTR_RO(name)
+
+ACCESS_ATTR(read_bandwidth);
+ACCESS_ATTR(read_latency);
+ACCESS_ATTR(write_bandwidth);
+ACCESS_ATTR(write_latency);
 
 static struct attribute *access_attrs[] = {
 	&dev_attr_read_bandwidth.attr,
@@ -225,7 +230,8 @@ static ssize_t name##_show(struct device *dev,				\
 			   struct device_attribute *attr,		\
 			   char *buf)					\
 {									\
-	return sprintf(buf, fmt "\n", to_cache_info(dev)->cache_attrs.name);\
+	return sysfs_emit(buf, fmt "\n",				\
+			  to_cache_info(dev)->cache_attrs.name);	\
 }									\
 DEVICE_ATTR_RO(name);
 
@@ -361,7 +367,7 @@ static void node_remove_caches(struct node *node) { }
 static ssize_t node_read_meminfo(struct device *dev,
 			struct device_attribute *attr, char *buf)
 {
-	int n;
+	int len = 0;
 	int nid = dev->id;
 	struct pglist_data *pgdat = NODE_DATA(nid);
 	struct sysinfo i;
@@ -370,128 +376,128 @@ static ssize_t node_read_meminfo(struct device *dev,
 	si_meminfo_node(&i, nid);
 	sreclaimable = node_page_state_pages(pgdat, NR_SLAB_RECLAIMABLE_B);
 	sunreclaimable = node_page_state_pages(pgdat, NR_SLAB_UNRECLAIMABLE_B);
-	n = sprintf(buf,
-		       "Node %d MemTotal:       %8lu kB\n"
-		       "Node %d MemFree:        %8lu kB\n"
-		       "Node %d MemUsed:        %8lu kB\n"
-		       "Node %d Active:         %8lu kB\n"
-		       "Node %d Inactive:       %8lu kB\n"
-		       "Node %d Active(anon):   %8lu kB\n"
-		       "Node %d Inactive(anon): %8lu kB\n"
-		       "Node %d Active(file):   %8lu kB\n"
-		       "Node %d Inactive(file): %8lu kB\n"
-		       "Node %d Unevictable:    %8lu kB\n"
-		       "Node %d Mlocked:        %8lu kB\n",
-		       nid, K(i.totalram),
-		       nid, K(i.freeram),
-		       nid, K(i.totalram - i.freeram),
-		       nid, K(node_page_state(pgdat, NR_ACTIVE_ANON) +
-				node_page_state(pgdat, NR_ACTIVE_FILE)),
-		       nid, K(node_page_state(pgdat, NR_INACTIVE_ANON) +
-				node_page_state(pgdat, NR_INACTIVE_FILE)),
-		       nid, K(node_page_state(pgdat, NR_ACTIVE_ANON)),
-		       nid, K(node_page_state(pgdat, NR_INACTIVE_ANON)),
-		       nid, K(node_page_state(pgdat, NR_ACTIVE_FILE)),
-		       nid, K(node_page_state(pgdat, NR_INACTIVE_FILE)),
-		       nid, K(node_page_state(pgdat, NR_UNEVICTABLE)),
-		       nid, K(sum_zone_node_page_state(nid, NR_MLOCK)));
+	len = sysfs_emit_at(buf, len,
+			    "Node %d MemTotal:       %8lu kB\n"
+			    "Node %d MemFree:        %8lu kB\n"
+			    "Node %d MemUsed:        %8lu kB\n"
+			    "Node %d Active:         %8lu kB\n"
+			    "Node %d Inactive:       %8lu kB\n"
+			    "Node %d Active(anon):   %8lu kB\n"
+			    "Node %d Inactive(anon): %8lu kB\n"
+			    "Node %d Active(file):   %8lu kB\n"
+			    "Node %d Inactive(file): %8lu kB\n"
+			    "Node %d Unevictable:    %8lu kB\n"
+			    "Node %d Mlocked:        %8lu kB\n",
+			    nid, K(i.totalram),
+			    nid, K(i.freeram),
+			    nid, K(i.totalram - i.freeram),
+			    nid, K(node_page_state(pgdat, NR_ACTIVE_ANON) +
+				   node_page_state(pgdat, NR_ACTIVE_FILE)),
+			    nid, K(node_page_state(pgdat, NR_INACTIVE_ANON) +
+				   node_page_state(pgdat, NR_INACTIVE_FILE)),
+			    nid, K(node_page_state(pgdat, NR_ACTIVE_ANON)),
+			    nid, K(node_page_state(pgdat, NR_INACTIVE_ANON)),
+			    nid, K(node_page_state(pgdat, NR_ACTIVE_FILE)),
+			    nid, K(node_page_state(pgdat, NR_INACTIVE_FILE)),
+			    nid, K(node_page_state(pgdat, NR_UNEVICTABLE)),
+			    nid, K(sum_zone_node_page_state(nid, NR_MLOCK)));
 
 #ifdef CONFIG_HIGHMEM
-	n += sprintf(buf + n,
-		       "Node %d HighTotal:      %8lu kB\n"
-		       "Node %d HighFree:       %8lu kB\n"
-		       "Node %d LowTotal:       %8lu kB\n"
-		       "Node %d LowFree:        %8lu kB\n",
-		       nid, K(i.totalhigh),
-		       nid, K(i.freehigh),
-		       nid, K(i.totalram - i.totalhigh),
-		       nid, K(i.freeram - i.freehigh));
+	len += sysfs_emit_at(buf, len,
+			     "Node %d HighTotal:      %8lu kB\n"
+			     "Node %d HighFree:       %8lu kB\n"
+			     "Node %d LowTotal:       %8lu kB\n"
+			     "Node %d LowFree:        %8lu kB\n",
+			     nid, K(i.totalhigh),
+			     nid, K(i.freehigh),
+			     nid, K(i.totalram - i.totalhigh),
+			     nid, K(i.freeram - i.freehigh));
 #endif
-	n += sprintf(buf + n,
-		       "Node %d Dirty:          %8lu kB\n"
-		       "Node %d Writeback:      %8lu kB\n"
-		       "Node %d FilePages:      %8lu kB\n"
-		       "Node %d Mapped:         %8lu kB\n"
-		       "Node %d AnonPages:      %8lu kB\n"
-		       "Node %d Shmem:          %8lu kB\n"
-		       "Node %d KernelStack:    %8lu kB\n"
+	len += sysfs_emit_at(buf, len,
+			     "Node %d Dirty:          %8lu kB\n"
+			     "Node %d Writeback:      %8lu kB\n"
+			     "Node %d FilePages:      %8lu kB\n"
+			     "Node %d Mapped:         %8lu kB\n"
+			     "Node %d AnonPages:      %8lu kB\n"
+			     "Node %d Shmem:          %8lu kB\n"
+			     "Node %d KernelStack:    %8lu kB\n"
 #ifdef CONFIG_SHADOW_CALL_STACK
-		       "Node %d ShadowCallStack:%8lu kB\n"
+			     "Node %d ShadowCallStack:%8lu kB\n"
 #endif
-		       "Node %d PageTables:     %8lu kB\n"
-		       "Node %d NFS_Unstable:   %8lu kB\n"
-		       "Node %d Bounce:         %8lu kB\n"
-		       "Node %d WritebackTmp:   %8lu kB\n"
-		       "Node %d KReclaimable:   %8lu kB\n"
-		       "Node %d Slab:           %8lu kB\n"
-		       "Node %d SReclaimable:   %8lu kB\n"
-		       "Node %d SUnreclaim:     %8lu kB\n"
+			     "Node %d PageTables:     %8lu kB\n"
+			     "Node %d NFS_Unstable:   %8lu kB\n"
+			     "Node %d Bounce:         %8lu kB\n"
+			     "Node %d WritebackTmp:   %8lu kB\n"
+			     "Node %d KReclaimable:   %8lu kB\n"
+			     "Node %d Slab:           %8lu kB\n"
+			     "Node %d SReclaimable:   %8lu kB\n"
+			     "Node %d SUnreclaim:     %8lu kB\n"
 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
-		       "Node %d AnonHugePages:  %8lu kB\n"
-		       "Node %d ShmemHugePages: %8lu kB\n"
-		       "Node %d ShmemPmdMapped: %8lu kB\n"
-		       "Node %d FileHugePages: %8lu kB\n"
-		       "Node %d FilePmdMapped: %8lu kB\n"
+			     "Node %d AnonHugePages:  %8lu kB\n"
+			     "Node %d ShmemHugePages: %8lu kB\n"
+			     "Node %d ShmemPmdMapped: %8lu kB\n"
+			     "Node %d FileHugePages: %8lu kB\n"
+			     "Node %d FilePmdMapped: %8lu kB\n"
 #endif
-			,
-		       nid, K(node_page_state(pgdat, NR_FILE_DIRTY)),
-		       nid, K(node_page_state(pgdat, NR_WRITEBACK)),
-		       nid, K(node_page_state(pgdat, NR_FILE_PAGES)),
-		       nid, K(node_page_state(pgdat, NR_FILE_MAPPED)),
-		       nid, K(node_page_state(pgdat, NR_ANON_MAPPED)),
-		       nid, K(i.sharedram),
-		       nid, node_page_state(pgdat, NR_KERNEL_STACK_KB),
+			     ,
+			     nid, K(node_page_state(pgdat, NR_FILE_DIRTY)),
+			     nid, K(node_page_state(pgdat, NR_WRITEBACK)),
+			     nid, K(node_page_state(pgdat, NR_FILE_PAGES)),
+			     nid, K(node_page_state(pgdat, NR_FILE_MAPPED)),
+			     nid, K(node_page_state(pgdat, NR_ANON_MAPPED)),
+			     nid, K(i.sharedram),
+			     nid, node_page_state(pgdat, NR_KERNEL_STACK_KB),
 #ifdef CONFIG_SHADOW_CALL_STACK
-		       nid, node_page_state(pgdat, NR_KERNEL_SCS_KB),
+			     nid, node_page_state(pgdat, NR_KERNEL_SCS_KB),
 #endif
-		       nid, K(sum_zone_node_page_state(nid, NR_PAGETABLE)),
-		       nid, 0UL,
-		       nid, K(sum_zone_node_page_state(nid, NR_BOUNCE)),
-		       nid, K(node_page_state(pgdat, NR_WRITEBACK_TEMP)),
-		       nid, K(sreclaimable +
-			      node_page_state(pgdat, NR_KERNEL_MISC_RECLAIMABLE)),
-		       nid, K(sreclaimable + sunreclaimable),
-		       nid, K(sreclaimable),
-		       nid, K(sunreclaimable)
+			     nid, K(sum_zone_node_page_state(nid, NR_PAGETABLE)),
+			     nid, 0UL,
+			     nid, K(sum_zone_node_page_state(nid, NR_BOUNCE)),
+			     nid, K(node_page_state(pgdat, NR_WRITEBACK_TEMP)),
+			     nid, K(sreclaimable +
+				    node_page_state(pgdat, NR_KERNEL_MISC_RECLAIMABLE)),
+			     nid, K(sreclaimable + sunreclaimable),
+			     nid, K(sreclaimable),
+			     nid, K(sunreclaimable)
 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
-		       ,
-		       nid, K(node_page_state(pgdat, NR_ANON_THPS) *
-				       HPAGE_PMD_NR),
-		       nid, K(node_page_state(pgdat, NR_SHMEM_THPS) *
-				       HPAGE_PMD_NR),
-		       nid, K(node_page_state(pgdat, NR_SHMEM_PMDMAPPED) *
-				       HPAGE_PMD_NR),
-		       nid, K(node_page_state(pgdat, NR_FILE_THPS) *
-				       HPAGE_PMD_NR),
-		       nid, K(node_page_state(pgdat, NR_FILE_PMDMAPPED) *
-				       HPAGE_PMD_NR)
+			     ,
+			     nid, K(node_page_state(pgdat, NR_ANON_THPS) *
+				    HPAGE_PMD_NR),
+			     nid, K(node_page_state(pgdat, NR_SHMEM_THPS) *
+				    HPAGE_PMD_NR),
+			     nid, K(node_page_state(pgdat, NR_SHMEM_PMDMAPPED) *
+				    HPAGE_PMD_NR),
+			     nid, K(node_page_state(pgdat, NR_FILE_THPS) *
+				    HPAGE_PMD_NR),
+			     nid, K(node_page_state(pgdat, NR_FILE_PMDMAPPED) *
+				    HPAGE_PMD_NR)
 #endif
-		       );
-	n += hugetlb_report_node_meminfo(nid, buf + n);
-	return n;
+			    );
+	len += hugetlb_report_node_meminfo(buf, len, nid);
+	return len;
 }
 
 #undef K
-static DEVICE_ATTR(meminfo, S_IRUGO, node_read_meminfo, NULL);
+static DEVICE_ATTR(meminfo, 0444, node_read_meminfo, NULL);
 
 static ssize_t node_read_numastat(struct device *dev,
-				struct device_attribute *attr, char *buf)
+				  struct device_attribute *attr, char *buf)
 {
-	return sprintf(buf,
-		       "numa_hit %lu\n"
-		       "numa_miss %lu\n"
-		       "numa_foreign %lu\n"
-		       "interleave_hit %lu\n"
-		       "local_node %lu\n"
-		       "other_node %lu\n",
-		       sum_zone_numa_state(dev->id, NUMA_HIT),
-		       sum_zone_numa_state(dev->id, NUMA_MISS),
-		       sum_zone_numa_state(dev->id, NUMA_FOREIGN),
-		       sum_zone_numa_state(dev->id, NUMA_INTERLEAVE_HIT),
-		       sum_zone_numa_state(dev->id, NUMA_LOCAL),
-		       sum_zone_numa_state(dev->id, NUMA_OTHER));
+	return sysfs_emit(buf,
+			  "numa_hit %lu\n"
+			  "numa_miss %lu\n"
+			  "numa_foreign %lu\n"
+			  "interleave_hit %lu\n"
+			  "local_node %lu\n"
+			  "other_node %lu\n",
+			  sum_zone_numa_state(dev->id, NUMA_HIT),
+			  sum_zone_numa_state(dev->id, NUMA_MISS),
+			  sum_zone_numa_state(dev->id, NUMA_FOREIGN),
+			  sum_zone_numa_state(dev->id, NUMA_INTERLEAVE_HIT),
+			  sum_zone_numa_state(dev->id, NUMA_LOCAL),
+			  sum_zone_numa_state(dev->id, NUMA_OTHER));
 }
-static DEVICE_ATTR(numastat, S_IRUGO, node_read_numastat, NULL);
+static DEVICE_ATTR(numastat, 0444, node_read_numastat, NULL);
 
 static ssize_t node_read_vmstat(struct device *dev,
 				struct device_attribute *attr, char *buf)
@@ -499,28 +505,31 @@ static ssize_t node_read_vmstat(struct device *dev,
 	int nid = dev->id;
 	struct pglist_data *pgdat = NODE_DATA(nid);
 	int i;
-	int n = 0;
+	int len = 0;
 
 	for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++)
-		n += sprintf(buf+n, "%s %lu\n", zone_stat_name(i),
-			     sum_zone_node_page_state(nid, i));
+		len += sysfs_emit_at(buf, len, "%s %lu\n",
+				     zone_stat_name(i),
+				     sum_zone_node_page_state(nid, i));
 
 #ifdef CONFIG_NUMA
 	for (i = 0; i < NR_VM_NUMA_STAT_ITEMS; i++)
-		n += sprintf(buf+n, "%s %lu\n", numa_stat_name(i),
-			     sum_zone_numa_state(nid, i));
-#endif
+		len += sysfs_emit_at(buf, len, "%s %lu\n",
+				     numa_stat_name(i),
+				     sum_zone_numa_state(nid, i));
 
+#endif
 	for (i = 0; i < NR_VM_NODE_STAT_ITEMS; i++)
-		n += sprintf(buf+n, "%s %lu\n", node_stat_name(i),
-			     node_page_state_pages(pgdat, i));
+		len += sysfs_emit_at(buf, len, "%s %lu\n",
+				     node_stat_name(i),
+				     node_page_state_pages(pgdat, i));
 
-	return n;
+	return len;
 }
-static DEVICE_ATTR(vmstat, S_IRUGO, node_read_vmstat, NULL);
+static DEVICE_ATTR(vmstat, 0444, node_read_vmstat, NULL);
 
 static ssize_t node_read_distance(struct device *dev,
-			struct device_attribute *attr, char *buf)
+				  struct device_attribute *attr, char *buf)
 {
 	int nid = dev->id;
 	int len = 0;
@@ -532,13 +541,15 @@ static ssize_t node_read_distance(struct device *dev,
 	 */
 	BUILD_BUG_ON(MAX_NUMNODES * 4 > PAGE_SIZE);
 
-	for_each_online_node(i)
-		len += sprintf(buf + len, "%s%d", i ? " " : "", node_distance(nid, i));
+	for_each_online_node(i) {
+		len += sysfs_emit_at(buf, len, "%s%d",
+				     i ? " " : "", node_distance(nid, i));
+	}
 
-	len += sprintf(buf + len, "\n");
+	len += sysfs_emit_at(buf, len, "\n");
 	return len;
 }
-static DEVICE_ATTR(distance, S_IRUGO, node_read_distance, NULL);
+static DEVICE_ATTR(distance, 0444, node_read_distance, NULL);
 
 static struct attribute *node_dev_attrs[] = {
 	&dev_attr_cpumap.attr,
@@ -970,17 +981,6 @@ void unregister_one_node(int nid)
  * node states attributes
  */
 
-static ssize_t print_nodes_state(enum node_states state, char *buf)
-{
-	int n;
-
-	n = scnprintf(buf, PAGE_SIZE - 1, "%*pbl",
-		      nodemask_pr_args(&node_states[state]));
-	buf[n++] = '\n';
-	buf[n] = '\0';
-	return n;
-}
-
 struct node_attr {
 	struct device_attribute attr;
 	enum node_states state;
@@ -990,7 +990,9 @@ static ssize_t show_node_state(struct device *dev,
 			       struct device_attribute *attr, char *buf)
 {
 	struct node_attr *na = container_of(attr, struct node_attr, attr);
-	return print_nodes_state(na->state, buf);
+
+	return sysfs_emit(buf, "%*pbl\n",
+			  nodemask_pr_args(&node_states[na->state]));
 }
 
 #define _NODE_ATTR(name, state) \