From 6365a1935c5151455812e96d8de434c551dc0d98 Mon Sep 17 00:00:00 2001
From: Ma Wupeng <mawupeng1@huawei.com>
Date: Tue, 14 Jun 2022 17:21:52 +0800
Subject: efi: Make code to find mirrored memory ranges generic

Commit b05b9f5f9dcf ("x86, mirror: x86 enabling - find mirrored memory
ranges") introduce the efi_find_mirror() function on x86. In order to reuse
the API we make it public.

Arm64 can support mirrored memory too, so function efi_find_mirror() is added to
efi_init() to this support for arm64.

Since efi_init() is shared by ARM, arm64 and riscv, this patch will bring
mirror memory support for these architectures, but this support is only tested
in arm64.

Signed-off-by: Ma Wupeng <mawupeng1@huawei.com>
Link: https://lore.kernel.org/r/20220614092156.1972846-2-mawupeng1@huawei.com
[ardb: fix subject to better reflect the payload]
Acked-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
---
 drivers/firmware/efi/efi-init.c |  1 +
 drivers/firmware/efi/efi.c      | 23 +++++++++++++++++++++++
 2 files changed, 24 insertions(+)

(limited to 'drivers')

diff --git a/drivers/firmware/efi/efi-init.c b/drivers/firmware/efi/efi-init.c
index b2c829e95bd1..3928dbff76d0 100644
--- a/drivers/firmware/efi/efi-init.c
+++ b/drivers/firmware/efi/efi-init.c
@@ -240,6 +240,7 @@ void __init efi_init(void)
 	 * And now, memblock is fully populated, it is time to do capping.
 	 */
 	early_init_dt_check_for_usable_mem_range();
+	efi_find_mirror();
 	efi_esrt_init();
 	efi_mokvar_table_init();
 
diff --git a/drivers/firmware/efi/efi.c b/drivers/firmware/efi/efi.c
index 860534bcfdac..79c232e07de7 100644
--- a/drivers/firmware/efi/efi.c
+++ b/drivers/firmware/efi/efi.c
@@ -446,6 +446,29 @@ err_put:
 
 subsys_initcall(efisubsys_init);
 
+void __init efi_find_mirror(void)
+{
+	efi_memory_desc_t *md;
+	u64 mirror_size = 0, total_size = 0;
+
+	if (!efi_enabled(EFI_MEMMAP))
+		return;
+
+	for_each_efi_memory_desc(md) {
+		unsigned long long start = md->phys_addr;
+		unsigned long long size = md->num_pages << EFI_PAGE_SHIFT;
+
+		total_size += size;
+		if (md->attribute & EFI_MEMORY_MORE_RELIABLE) {
+			memblock_mark_mirror(start, size);
+			mirror_size += size;
+		}
+	}
+	if (mirror_size)
+		pr_info("Memory: %lldM/%lldM mirrored memory\n",
+			mirror_size>>20, total_size>>20);
+}
+
 /*
  * Find the efi memory descriptor for a given physical address.  Given a
  * physical address, determine if it exists within an EFI Memory Map entry,
-- 
cgit v1.2.3


From db01ea882bf601252dad57242655da17fd9ad2f5 Mon Sep 17 00:00:00 2001
From: Liu Zixian <liuzixian4@huawei.com>
Date: Tue, 14 Jun 2022 19:48:05 +0800
Subject: efi: Correct comment on efi_memmap_alloc

Returning zero means success now.

Signed-off-by: Liu Zixian <liuzixian4@huawei.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
---
 drivers/firmware/efi/memmap.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

(limited to 'drivers')

diff --git a/drivers/firmware/efi/memmap.c b/drivers/firmware/efi/memmap.c
index 4df55a55da84..cf87dd7bbd25 100644
--- a/drivers/firmware/efi/memmap.c
+++ b/drivers/firmware/efi/memmap.c
@@ -59,8 +59,7 @@ static void __init efi_memmap_free(void)
  * Depending on whether mm_init() has already been invoked or not,
  * either memblock or "normal" page allocation is used.
  *
- * Returns the physical address of the allocated memory map on
- * success, zero on failure.
+ * Returns zero on success, a negative error code on failure.
  */
 int __init efi_memmap_alloc(unsigned int num_entries,
 		struct efi_memory_map_data *data)
-- 
cgit v1.2.3


From 3881ee0b1edce0ece72d24b7c74f46b73bd6dcba Mon Sep 17 00:00:00 2001
From: Ard Biesheuvel <ardb@kernel.org>
Date: Fri, 17 Jun 2022 10:34:48 +0200
Subject: efi: avoid efivars layer when loading SSDTs from variables

The efivars intermediate variable access layer provides an abstraction
that permits the EFI variable store to be replaced by something else
that implements a compatible interface, and caches all variables in the
variable store for fast access via the efivarfs pseudo-filesystem.

The SSDT override feature does not take advantage of either feature, as
it is only used when the generic EFI implementation of efivars is used,
and it traverses all variables only once to find the ones it is
interested in, and frees all data structures that the efivars layer
keeps right after.

So in this case, let's just call EFI's code directly, using the function
pointers in struct efi.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
---
 drivers/firmware/efi/efi.c | 103 ++++++++++++++++++---------------------------
 1 file changed, 41 insertions(+), 62 deletions(-)

(limited to 'drivers')

diff --git a/drivers/firmware/efi/efi.c b/drivers/firmware/efi/efi.c
index 79c232e07de7..7f06065d3eb0 100644
--- a/drivers/firmware/efi/efi.c
+++ b/drivers/firmware/efi/efi.c
@@ -202,7 +202,7 @@ static void generic_ops_unregister(void)
 }
 
 #ifdef CONFIG_EFI_CUSTOM_SSDT_OVERLAYS
-#define EFIVAR_SSDT_NAME_MAX	16
+#define EFIVAR_SSDT_NAME_MAX	16UL
 static char efivar_ssdt[EFIVAR_SSDT_NAME_MAX] __initdata;
 static int __init efivar_ssdt_setup(char *str)
 {
@@ -219,83 +219,62 @@ static int __init efivar_ssdt_setup(char *str)
 }
 __setup("efivar_ssdt=", efivar_ssdt_setup);
 
-static __init int efivar_ssdt_iter(efi_char16_t *name, efi_guid_t vendor,
-				   unsigned long name_size, void *data)
-{
-	struct efivar_entry *entry;
-	struct list_head *list = data;
-	char utf8_name[EFIVAR_SSDT_NAME_MAX];
-	int limit = min_t(unsigned long, EFIVAR_SSDT_NAME_MAX, name_size);
-
-	ucs2_as_utf8(utf8_name, name, limit - 1);
-	if (strncmp(utf8_name, efivar_ssdt, limit) != 0)
-		return 0;
-
-	entry = kmalloc(sizeof(*entry), GFP_KERNEL);
-	if (!entry)
-		return 0;
-
-	memcpy(entry->var.VariableName, name, name_size);
-	memcpy(&entry->var.VendorGuid, &vendor, sizeof(efi_guid_t));
-
-	efivar_entry_add(entry, list);
-
-	return 0;
-}
-
 static __init int efivar_ssdt_load(void)
 {
-	LIST_HEAD(entries);
-	struct efivar_entry *entry, *aux;
-	unsigned long size;
-	void *data;
-	int ret;
+	unsigned long name_size = 256;
+	efi_char16_t *name = NULL;
+	efi_status_t status;
+	efi_guid_t guid;
 
 	if (!efivar_ssdt[0])
 		return 0;
 
-	ret = efivar_init(efivar_ssdt_iter, &entries, true, &entries);
-
-	list_for_each_entry_safe(entry, aux, &entries, list) {
-		pr_info("loading SSDT from variable %s-%pUl\n", efivar_ssdt,
-			&entry->var.VendorGuid);
+	name = kzalloc(name_size, GFP_KERNEL);
+	if (!name)
+		return -ENOMEM;
 
-		list_del(&entry->list);
+	for (;;) {
+		char utf8_name[EFIVAR_SSDT_NAME_MAX];
+		unsigned long data_size = 0;
+		void *data;
+		int limit;
 
-		ret = efivar_entry_size(entry, &size);
-		if (ret) {
-			pr_err("failed to get var size\n");
-			goto free_entry;
+		status = efi.get_next_variable(&name_size, name, &guid);
+		if (status == EFI_NOT_FOUND) {
+			break;
+		} else if (status == EFI_BUFFER_TOO_SMALL) {
+			name = krealloc(name, name_size, GFP_KERNEL);
+			if (!name)
+				return -ENOMEM;
+			continue;
 		}
 
-		data = kmalloc(size, GFP_KERNEL);
-		if (!data) {
-			ret = -ENOMEM;
-			goto free_entry;
-		}
+		limit = min(EFIVAR_SSDT_NAME_MAX, name_size);
+		ucs2_as_utf8(utf8_name, name, limit - 1);
+		if (strncmp(utf8_name, efivar_ssdt, limit) != 0)
+			continue;
 
-		ret = efivar_entry_get(entry, NULL, &size, data);
-		if (ret) {
-			pr_err("failed to get var data\n");
-			goto free_data;
-		}
+		pr_info("loading SSDT from variable %s-%pUl\n", efivar_ssdt, &guid);
 
-		ret = acpi_load_table(data, NULL);
-		if (ret) {
-			pr_err("failed to load table: %d\n", ret);
-			goto free_data;
-		}
+		status = efi.get_variable(name, &guid, NULL, &data_size, NULL);
+		if (status != EFI_BUFFER_TOO_SMALL || !data_size)
+			return -EIO;
 
-		goto free_entry;
+		data = kmalloc(data_size, GFP_KERNEL);
+		if (!data)
+			return -ENOMEM;
 
-free_data:
+		status = efi.get_variable(name, &guid, NULL, &data_size, data);
+		if (status == EFI_SUCCESS) {
+			acpi_status ret = acpi_load_table(data, NULL);
+			if (ret)
+				pr_err("failed to load table: %u\n", ret);
+		} else {
+			pr_err("failed to get var data: 0x%lx\n", status);
+		}
 		kfree(data);
-
-free_entry:
-		kfree(entry);
 	}
-
-	return ret;
+	return 0;
 }
 #else
 static inline int efivar_ssdt_load(void) { return 0; }
-- 
cgit v1.2.3


From 416581e486798cbe3e2b3306faee7d7e9bf3c3d4 Mon Sep 17 00:00:00 2001
From: Ard Biesheuvel <ardb@kernel.org>
Date: Mon, 20 Jun 2022 11:35:37 +0200
Subject: efi: efibc: avoid efivar API for setting variables

Avoid abusing the efivar API by passing locally instantiated
efivar_entry structs into efivar_set_entry_safe(), rather than using the
API as intended. Instead, just call efi.set_variable() directly.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
---
 drivers/firmware/efi/Kconfig |  1 +
 drivers/firmware/efi/efibc.c | 76 +++++++++++++++++---------------------------
 2 files changed, 30 insertions(+), 47 deletions(-)

(limited to 'drivers')

diff --git a/drivers/firmware/efi/Kconfig b/drivers/firmware/efi/Kconfig
index 7aa4717cdcac..6fd4414c4836 100644
--- a/drivers/firmware/efi/Kconfig
+++ b/drivers/firmware/efi/Kconfig
@@ -145,6 +145,7 @@ config EFI_GENERIC_STUB_INITRD_CMDLINE_LOADER
 
 config EFI_BOOTLOADER_CONTROL
 	tristate "EFI Bootloader Control"
+	select UCS2_STRING
 	default n
 	help
 	  This module installs a reboot hook, such that if reboot() is
diff --git a/drivers/firmware/efi/efibc.c b/drivers/firmware/efi/efibc.c
index 15a47539dc56..8ced7af8e56d 100644
--- a/drivers/firmware/efi/efibc.c
+++ b/drivers/firmware/efi/efibc.c
@@ -10,69 +10,51 @@
 #include <linux/module.h>
 #include <linux/reboot.h>
 #include <linux/slab.h>
+#include <linux/ucs2_string.h>
 
-static void efibc_str_to_str16(const char *str, efi_char16_t *str16)
-{
-	size_t i;
-
-	for (i = 0; i < strlen(str); i++)
-		str16[i] = str[i];
-
-	str16[i] = '\0';
-}
+#define MAX_DATA_LEN	512
 
-static int efibc_set_variable(const char *name, const char *value)
+static int efibc_set_variable(efi_char16_t *name, efi_char16_t *value,
+			      unsigned long len)
 {
-	int ret;
-	efi_guid_t guid = LINUX_EFI_LOADER_ENTRY_GUID;
-	struct efivar_entry *entry;
-	size_t size = (strlen(value) + 1) * sizeof(efi_char16_t);
+	efi_status_t status;
 
-	if (size > sizeof(entry->var.Data)) {
-		pr_err("value is too large (%zu bytes) for '%s' EFI variable\n", size, name);
-		return -EINVAL;
-	}
+	status = efi.set_variable(name, &LINUX_EFI_LOADER_ENTRY_GUID,
+				  EFI_VARIABLE_NON_VOLATILE
+				  | EFI_VARIABLE_BOOTSERVICE_ACCESS
+				  | EFI_VARIABLE_RUNTIME_ACCESS,
+				  len * sizeof(efi_char16_t), value);
 
-	entry = kmalloc(sizeof(*entry), GFP_KERNEL);
-	if (!entry) {
-		pr_err("failed to allocate efivar entry for '%s' EFI variable\n", name);
-		return -ENOMEM;
+	if (status != EFI_SUCCESS) {
+		pr_err("failed to set EFI variable: 0x%lx\n", status);
+		return -EIO;
 	}
-
-	efibc_str_to_str16(name, entry->var.VariableName);
-	efibc_str_to_str16(value, (efi_char16_t *)entry->var.Data);
-	memcpy(&entry->var.VendorGuid, &guid, sizeof(guid));
-
-	ret = efivar_entry_set_safe(entry->var.VariableName,
-				    entry->var.VendorGuid,
-				    EFI_VARIABLE_NON_VOLATILE
-				    | EFI_VARIABLE_BOOTSERVICE_ACCESS
-				    | EFI_VARIABLE_RUNTIME_ACCESS,
-				    false, size, entry->var.Data);
-
-	if (ret)
-		pr_err("failed to set %s EFI variable: 0x%x\n",
-		       name, ret);
-
-	kfree(entry);
-	return ret;
+	return 0;
 }
 
 static int efibc_reboot_notifier_call(struct notifier_block *notifier,
 				      unsigned long event, void *data)
 {
-	const char *reason = "shutdown";
+	efi_char16_t *reason = event == SYS_RESTART ? L"reboot"
+						    : L"shutdown";
+	const u8 *str = data;
+	efi_char16_t *wdata;
+	unsigned long l;
 	int ret;
 
-	if (event == SYS_RESTART)
-		reason = "reboot";
-
-	ret = efibc_set_variable("LoaderEntryRebootReason", reason);
+	ret = efibc_set_variable(L"LoaderEntryRebootReason", reason,
+				 ucs2_strlen(reason));
 	if (ret || !data)
 		return NOTIFY_DONE;
 
-	efibc_set_variable("LoaderEntryOneShot", (char *)data);
+	wdata = kmalloc(MAX_DATA_LEN * sizeof(efi_char16_t), GFP_KERNEL);
+	for (l = 0; l < MAX_DATA_LEN - 1 && str[l] != '\0'; l++)
+		wdata[l] = str[l];
+	wdata[l] = L'\0';
+
+	efibc_set_variable(L"LoaderEntryOneShot", wdata, l);
 
+	kfree(wdata);
 	return NOTIFY_DONE;
 }
 
@@ -84,7 +66,7 @@ static int __init efibc_init(void)
 {
 	int ret;
 
-	if (!efivars_kobject() || !efivar_supports_writes())
+	if (!efi_rt_services_supported(EFI_RT_SUPPORTED_SET_VARIABLE))
 		return -ENODEV;
 
 	ret = register_reboot_notifier(&efibc_reboot_notifier);
-- 
cgit v1.2.3


From 38d4f74bc14847491d07bd745dc4a2c274f4987d Mon Sep 17 00:00:00 2001
From: Ard Biesheuvel <ardb@kernel.org>
Date: Mon, 20 Jun 2022 12:03:50 +0200
Subject: media: atomisp_gmin_platform: stop abusing efivar API

As the code comment already suggests, using the efivar API in this way
is not how it is intended, and so let's switch to the right one, which
is simply to call efi.get_variable() directly after checking whether or
not the GetVariable() runtime service is supported.

Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
---
 .../media/atomisp/pci/atomisp_gmin_platform.c      | 27 +++++-----------------
 1 file changed, 6 insertions(+), 21 deletions(-)

(limited to 'drivers')

diff --git a/drivers/staging/media/atomisp/pci/atomisp_gmin_platform.c b/drivers/staging/media/atomisp/pci/atomisp_gmin_platform.c
index 7e47db82de07..bf527b366ab3 100644
--- a/drivers/staging/media/atomisp/pci/atomisp_gmin_platform.c
+++ b/drivers/staging/media/atomisp/pci/atomisp_gmin_platform.c
@@ -1284,7 +1284,7 @@ static int gmin_get_config_var(struct device *maindev,
 	const struct dmi_system_id *id;
 	struct device *dev = maindev;
 	char var8[CFG_VAR_NAME_MAX];
-	struct efivar_entry *ev;
+	efi_status_t status;
 	int i, ret;
 
 	/* For sensors, try first to use the _DSM table */
@@ -1326,24 +1326,11 @@ static int gmin_get_config_var(struct device *maindev,
 	for (i = 0; i < sizeof(var8) && var8[i]; i++)
 		var16[i] = var8[i];
 
-	/* Not sure this API usage is kosher; efivar_entry_get()'s
-	 * implementation simply uses VariableName and VendorGuid from
-	 * the struct and ignores the rest, but it seems like there
-	 * ought to be an "official" efivar_entry registered
-	 * somewhere?
-	 */
-	ev = kzalloc(sizeof(*ev), GFP_KERNEL);
-	if (!ev)
-		return -ENOMEM;
-	memcpy(&ev->var.VariableName, var16, sizeof(var16));
-	ev->var.VendorGuid = GMIN_CFG_VAR_EFI_GUID;
-	ev->var.DataSize = *out_len;
-
-	ret = efivar_entry_get(ev, &ev->var.Attributes,
-			       &ev->var.DataSize, ev->var.Data);
-	if (ret == 0) {
-		memcpy(out, ev->var.Data, ev->var.DataSize);
-		*out_len = ev->var.DataSize;
+	status = EFI_UNSUPPORTED;
+	if (efi_rt_services_supported(EFI_RT_SUPPORTED_GET_VARIABLE))
+		status = efi.get_variable(var16, &GMIN_CFG_VAR_EFI_GUID, NULL,
+					  (unsigned long *)out_len, out);
+	if (status == EFI_SUCCESS) {
 		dev_info(maindev, "found EFI entry for '%s'\n", var8);
 	} else if (is_gmin) {
 		dev_info(maindev, "Failed to find EFI gmin variable %s\n", var8);
@@ -1351,8 +1338,6 @@ static int gmin_get_config_var(struct device *maindev,
 		dev_info(maindev, "Failed to find EFI variable %s\n", var8);
 	}
 
-	kfree(ev);
-
 	return ret;
 }
 
-- 
cgit v1.2.3


From 0c4bad7f47c4e5ff82c82fbdd4f4ab3105b98fc9 Mon Sep 17 00:00:00 2001
From: Ard Biesheuvel <ardb@kernel.org>
Date: Fri, 17 Jun 2022 19:00:06 +0200
Subject: iwlwifi: Switch to proper EFI variable store interface

Using half of the efivar API with locally baked efivar_entry instances
is not the right way to use this API, and these uses impede planned work
on the efivar layer itself.

So switch to direct EFI variable store accesses: we don't need the
efivar layer anyway.

Acked-by: Kalle Valo <kvalo@kernel.org>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
---
 drivers/net/wireless/intel/iwlwifi/fw/uefi.c | 96 ++++++++++------------------
 1 file changed, 32 insertions(+), 64 deletions(-)

(limited to 'drivers')

diff --git a/drivers/net/wireless/intel/iwlwifi/fw/uefi.c b/drivers/net/wireless/intel/iwlwifi/fw/uefi.c
index 23b1d689ba7b..6d408cd0f517 100644
--- a/drivers/net/wireless/intel/iwlwifi/fw/uefi.c
+++ b/drivers/net/wireless/intel/iwlwifi/fw/uefi.c
@@ -19,20 +19,14 @@
 
 void *iwl_uefi_get_pnvm(struct iwl_trans *trans, size_t *len)
 {
-	struct efivar_entry *pnvm_efivar;
 	void *data;
 	unsigned long package_size;
-	int err;
+	efi_status_t status;
 
 	*len = 0;
 
-	pnvm_efivar = kzalloc(sizeof(*pnvm_efivar), GFP_KERNEL);
-	if (!pnvm_efivar)
-		return ERR_PTR(-ENOMEM);
-
-	memcpy(&pnvm_efivar->var.VariableName, IWL_UEFI_OEM_PNVM_NAME,
-	       sizeof(IWL_UEFI_OEM_PNVM_NAME));
-	pnvm_efivar->var.VendorGuid = IWL_EFI_VAR_GUID;
+	if (!efi_rt_services_supported(EFI_RT_SUPPORTED_GET_VARIABLE))
+		return ERR_PTR(-ENODEV);
 
 	/*
 	 * TODO: we hardcode a maximum length here, because reading
@@ -42,27 +36,22 @@ void *iwl_uefi_get_pnvm(struct iwl_trans *trans, size_t *len)
 	package_size = IWL_HARDCODED_PNVM_SIZE;
 
 	data = kmalloc(package_size, GFP_KERNEL);
-	if (!data) {
-		data = ERR_PTR(-ENOMEM);
-		goto out;
-	}
+	if (!data)
+		return ERR_PTR(-ENOMEM);
 
-	err = efivar_entry_get(pnvm_efivar, NULL, &package_size, data);
-	if (err) {
+	status = efi.get_variable(IWL_UEFI_OEM_PNVM_NAME, &IWL_EFI_VAR_GUID,
+				  NULL, &package_size, data);
+	if (status != EFI_SUCCESS) {
 		IWL_DEBUG_FW(trans,
-			     "PNVM UEFI variable not found %d (len %lu)\n",
-			     err, package_size);
+			     "PNVM UEFI variable not found 0x%lx (len %lu)\n",
+			     status, package_size);
 		kfree(data);
-		data = ERR_PTR(err);
-		goto out;
+		return ERR_PTR(-ENOENT);
 	}
 
 	IWL_DEBUG_FW(trans, "Read PNVM from UEFI with size %lu\n", package_size);
 	*len = package_size;
 
-out:
-	kfree(pnvm_efivar);
-
 	return data;
 }
 
@@ -211,21 +200,15 @@ static void *iwl_uefi_reduce_power_parse(struct iwl_trans *trans,
 
 void *iwl_uefi_get_reduced_power(struct iwl_trans *trans, size_t *len)
 {
-	struct efivar_entry *reduce_power_efivar;
 	struct pnvm_sku_package *package;
 	void *data = NULL;
 	unsigned long package_size;
-	int err;
+	efi_status_t status;
 
 	*len = 0;
 
-	reduce_power_efivar = kzalloc(sizeof(*reduce_power_efivar), GFP_KERNEL);
-	if (!reduce_power_efivar)
-		return ERR_PTR(-ENOMEM);
-
-	memcpy(&reduce_power_efivar->var.VariableName, IWL_UEFI_REDUCED_POWER_NAME,
-	       sizeof(IWL_UEFI_REDUCED_POWER_NAME));
-	reduce_power_efivar->var.VendorGuid = IWL_EFI_VAR_GUID;
+	if (!efi_rt_services_supported(EFI_RT_SUPPORTED_GET_VARIABLE))
+		return ERR_PTR(-ENODEV);
 
 	/*
 	 * TODO: we hardcode a maximum length here, because reading
@@ -235,19 +218,17 @@ void *iwl_uefi_get_reduced_power(struct iwl_trans *trans, size_t *len)
 	package_size = IWL_HARDCODED_REDUCE_POWER_SIZE;
 
 	package = kmalloc(package_size, GFP_KERNEL);
-	if (!package) {
-		package = ERR_PTR(-ENOMEM);
-		goto out;
-	}
+	if (!package)
+		return ERR_PTR(-ENOMEM);
 
-	err = efivar_entry_get(reduce_power_efivar, NULL, &package_size, package);
-	if (err) {
+	status = efi.get_variable(IWL_UEFI_REDUCED_POWER_NAME, &IWL_EFI_VAR_GUID,
+				  NULL, &package_size, data);
+	if (status != EFI_SUCCESS) {
 		IWL_DEBUG_FW(trans,
-			     "Reduced Power UEFI variable not found %d (len %lu)\n",
-			     err, package_size);
+			     "Reduced Power UEFI variable not found 0x%lx (len %lu)\n",
+			     status, package_size);
 		kfree(package);
-		data = ERR_PTR(err);
-		goto out;
+		return ERR_PTR(-ENOENT);
 	}
 
 	IWL_DEBUG_FW(trans, "Read reduced power from UEFI with size %lu\n",
@@ -262,9 +243,6 @@ void *iwl_uefi_get_reduced_power(struct iwl_trans *trans, size_t *len)
 
 	kfree(package);
 
-out:
-	kfree(reduce_power_efivar);
-
 	return data;
 }
 
@@ -304,22 +282,15 @@ static int iwl_uefi_sgom_parse(struct uefi_cnv_wlan_sgom_data *sgom_data,
 void iwl_uefi_get_sgom_table(struct iwl_trans *trans,
 			     struct iwl_fw_runtime *fwrt)
 {
-	struct efivar_entry *sgom_efivar;
 	struct uefi_cnv_wlan_sgom_data *data;
 	unsigned long package_size;
-	int err, ret;
-
-	if (!fwrt->geo_enabled)
-		return;
+	efi_status_t status;
+	int ret;
 
-	sgom_efivar = kzalloc(sizeof(*sgom_efivar), GFP_KERNEL);
-	if (!sgom_efivar)
+	if (!fwrt->geo_enabled ||
+	    !efi_rt_services_supported(EFI_RT_SUPPORTED_GET_VARIABLE))
 		return;
 
-	memcpy(&sgom_efivar->var.VariableName, IWL_UEFI_SGOM_NAME,
-	       sizeof(IWL_UEFI_SGOM_NAME));
-	sgom_efivar->var.VendorGuid = IWL_EFI_VAR_GUID;
-
 	/* TODO: we hardcode a maximum length here, because reading
 	 * from the UEFI is not working.  To implement this properly,
 	 * we have to call efivar_entry_size().
@@ -327,15 +298,14 @@ void iwl_uefi_get_sgom_table(struct iwl_trans *trans,
 	package_size = IWL_HARDCODED_SGOM_SIZE;
 
 	data = kmalloc(package_size, GFP_KERNEL);
-	if (!data) {
-		data = ERR_PTR(-ENOMEM);
-		goto out;
-	}
+	if (!data)
+		return;
 
-	err = efivar_entry_get(sgom_efivar, NULL, &package_size, data);
-	if (err) {
+	status = efi.get_variable(IWL_UEFI_SGOM_NAME, &IWL_EFI_VAR_GUID,
+				  NULL, &package_size, data);
+	if (status != EFI_SUCCESS) {
 		IWL_DEBUG_FW(trans,
-			     "SGOM UEFI variable not found %d\n", err);
+			     "SGOM UEFI variable not found 0x%lx\n", status);
 		goto out_free;
 	}
 
@@ -349,8 +319,6 @@ void iwl_uefi_get_sgom_table(struct iwl_trans *trans,
 out_free:
 	kfree(data);
 
-out:
-	kfree(sgom_efivar);
 }
 IWL_EXPORT_SYMBOL(iwl_uefi_get_sgom_table);
 #endif /* CONFIG_ACPI */
-- 
cgit v1.2.3


From 98e152c19b66cfe44e1924d2554626a25758f1ea Mon Sep 17 00:00:00 2001
From: Ard Biesheuvel <ardb@kernel.org>
Date: Fri, 17 Jun 2022 18:12:06 +0200
Subject: brcmfmac: Switch to appropriate helper to load EFI variable contents

Avoid abusing the efivar layer by invoking it with locally constructed
efivar_entry instances, and instead, just call the EFI routines directly
if available.

Acked-by: Kalle Valo <kvalo@kernel.org>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
---
 .../broadcom/brcm80211/brcmfmac/firmware.c         | 25 +++++++---------------
 1 file changed, 8 insertions(+), 17 deletions(-)

(limited to 'drivers')

diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/firmware.c b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/firmware.c
index dcbe55b56e43..b8379e4034a4 100644
--- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/firmware.c
+++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/firmware.c
@@ -459,43 +459,34 @@ static void brcmf_fw_fix_efi_nvram_ccode(char *data, unsigned long data_len)
 
 static u8 *brcmf_fw_nvram_from_efi(size_t *data_len_ret)
 {
-	const u16 name[] = { 'n', 'v', 'r', 'a', 'm', 0 };
-	struct efivar_entry *nvram_efivar;
+	efi_guid_t guid = EFI_GUID(0x74b00bd9, 0x805a, 0x4d61, 0xb5, 0x1f,
+				   0x43, 0x26, 0x81, 0x23, 0xd1, 0x13);
 	unsigned long data_len = 0;
+	efi_status_t status;
 	u8 *data = NULL;
-	int err;
 
-	nvram_efivar = kzalloc(sizeof(*nvram_efivar), GFP_KERNEL);
-	if (!nvram_efivar)
+	if (!efi_rt_services_supported(EFI_RT_SUPPORTED_GET_VARIABLE))
 		return NULL;
 
-	memcpy(&nvram_efivar->var.VariableName, name, sizeof(name));
-	nvram_efivar->var.VendorGuid = EFI_GUID(0x74b00bd9, 0x805a, 0x4d61,
-						0xb5, 0x1f, 0x43, 0x26,
-						0x81, 0x23, 0xd1, 0x13);
-
-	err = efivar_entry_size(nvram_efivar, &data_len);
-	if (err)
+	status = efi.get_variable(L"nvram", &guid, NULL, &data_len, NULL);
+	if (status != EFI_BUFFER_TOO_SMALL)
 		goto fail;
 
 	data = kmalloc(data_len, GFP_KERNEL);
 	if (!data)
 		goto fail;
 
-	err = efivar_entry_get(nvram_efivar, NULL, &data_len, data);
-	if (err)
+	status = efi.get_variable(L"nvram", &guid, NULL, &data_len, data);
+	if (status != EFI_SUCCESS)
 		goto fail;
 
 	brcmf_fw_fix_efi_nvram_ccode(data, data_len);
 	brcmf_info("Using nvram EFI variable\n");
 
-	kfree(nvram_efivar);
 	*data_len_ret = data_len;
 	return data;
-
 fail:
 	kfree(data);
-	kfree(nvram_efivar);
 	return NULL;
 }
 #else
-- 
cgit v1.2.3


From f662092b2e0c4a43d09e5b1f67ca969ea47a93d3 Mon Sep 17 00:00:00 2001
From: Ard Biesheuvel <ardb@kernel.org>
Date: Fri, 17 Jun 2022 18:34:06 +0200
Subject: Input: applespi - avoid efivars API and invoke EFI services directly

This driver abuses the efivar API, by using a few of its helpers on
entries that were not instantiated by the API itself. This is a problem
as future cleanup work on efivars is complicated by this.

So let's just switch to the get/set variable runtime wrappers directly.

Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
---
 drivers/input/keyboard/applespi.c | 42 +++++++++++++--------------------------
 1 file changed, 14 insertions(+), 28 deletions(-)

(limited to 'drivers')

diff --git a/drivers/input/keyboard/applespi.c b/drivers/input/keyboard/applespi.c
index d1f5354d5ea2..cbc6c0d4670a 100644
--- a/drivers/input/keyboard/applespi.c
+++ b/drivers/input/keyboard/applespi.c
@@ -1597,52 +1597,38 @@ static u32 applespi_notify(acpi_handle gpe_device, u32 gpe, void *context)
 
 static int applespi_get_saved_bl_level(struct applespi_data *applespi)
 {
-	struct efivar_entry *efivar_entry;
+	efi_status_t sts = EFI_NOT_FOUND;
 	u16 efi_data = 0;
-	unsigned long efi_data_len;
-	int sts;
-
-	efivar_entry = kmalloc(sizeof(*efivar_entry), GFP_KERNEL);
-	if (!efivar_entry)
-		return -ENOMEM;
-
-	memcpy(efivar_entry->var.VariableName, EFI_BL_LEVEL_NAME,
-	       sizeof(EFI_BL_LEVEL_NAME));
-	efivar_entry->var.VendorGuid = EFI_BL_LEVEL_GUID;
-	efi_data_len = sizeof(efi_data);
+	unsigned long efi_data_len = sizeof(efi_data);
 
-	sts = efivar_entry_get(efivar_entry, NULL, &efi_data_len, &efi_data);
-	if (sts && sts != -ENOENT)
+	if (efi_rt_services_supported(EFI_RT_SUPPORTED_GET_VARIABLE))
+		sts = efi.get_variable(EFI_BL_LEVEL_NAME, &EFI_BL_LEVEL_GUID,
+				       NULL, &efi_data_len, &efi_data);
+	if (sts != EFI_SUCCESS && sts != EFI_NOT_FOUND)
 		dev_warn(&applespi->spi->dev,
-			 "Error getting backlight level from EFI vars: %d\n",
+			 "Error getting backlight level from EFI vars: 0x%lx\n",
 			 sts);
 
-	kfree(efivar_entry);
-
-	return sts ? sts : efi_data;
+	return sts != EFI_SUCCESS ? -ENODEV : efi_data;
 }
 
 static void applespi_save_bl_level(struct applespi_data *applespi,
 				   unsigned int level)
 {
-	efi_guid_t efi_guid;
+	efi_status_t sts = EFI_UNSUPPORTED;
 	u32 efi_attr;
-	unsigned long efi_data_len;
 	u16 efi_data;
-	int sts;
 
-	/* Save keyboard backlight level */
-	efi_guid = EFI_BL_LEVEL_GUID;
 	efi_data = (u16)level;
-	efi_data_len = sizeof(efi_data);
 	efi_attr = EFI_VARIABLE_NON_VOLATILE | EFI_VARIABLE_BOOTSERVICE_ACCESS |
 		   EFI_VARIABLE_RUNTIME_ACCESS;
 
-	sts = efivar_entry_set_safe((efi_char16_t *)EFI_BL_LEVEL_NAME, efi_guid,
-				    efi_attr, true, efi_data_len, &efi_data);
-	if (sts)
+	if (efi_rt_services_supported(EFI_RT_SUPPORTED_SET_VARIABLE))
+		sts = efi.set_variable(EFI_BL_LEVEL_NAME, &EFI_BL_LEVEL_GUID,
+				       efi_attr, sizeof(efi_data), &efi_data);
+	if (sts != EFI_SUCCESS)
 		dev_warn(&applespi->spi->dev,
-			 "Error saving backlight level to EFI vars: %d\n", sts);
+			 "Error saving backlight level to EFI vars: 0x%lx\n", sts);
 }
 
 static int applespi_probe(struct spi_device *spi)
-- 
cgit v1.2.3


From ec3507b2ca51286de6ecd85fdac8e722219cdef8 Mon Sep 17 00:00:00 2001
From: Ard Biesheuvel <ardb@kernel.org>
Date: Mon, 20 Jun 2022 17:04:32 +0200
Subject: efi: vars: Don't drop lock in the middle of efivar_init()

Even though the efivars_lock lock is documented as protecting the
efivars->ops pointer (among other things), efivar_init() happily
releases and reacquires the lock for every EFI variable that it
enumerates. This used to be needed because the lock was originally a
spinlock, which prevented the callback that is invoked for every
variable from being able to sleep. However, releasing the lock could
potentially invalidate the ops pointer, but more importantly, it might
allow a SetVariable() runtime service call to take place concurrently,
and the UEFI spec does not define how this affects an enumeration that
is running in parallel using the GetNextVariable() runtime service,
which is what efivar_init() uses.

In the meantime, the lock has been converted into a semaphore, and the
only reason we need to drop the lock is because the efivarfs pseudo
filesystem driver will otherwise deadlock when it invokes the efivars
API from the callback to create the efivar_entry items and insert them
into the linked list. (EFI pstore is affected in a similar way)

So let's switch to helpers that can be used while the lock is already
taken. This way, we can hold on to the lock throughout the enumeration.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
---
 drivers/firmware/efi/efi-pstore.c |  7 ++-----
 drivers/firmware/efi/efivars.c    |  5 +----
 drivers/firmware/efi/vars.c       | 22 +++++++++++-----------
 3 files changed, 14 insertions(+), 20 deletions(-)

(limited to 'drivers')

diff --git a/drivers/firmware/efi/efi-pstore.c b/drivers/firmware/efi/efi-pstore.c
index 7e771c56c13c..0d80cc7ff6ca 100644
--- a/drivers/firmware/efi/efi-pstore.c
+++ b/drivers/firmware/efi/efi-pstore.c
@@ -364,7 +364,6 @@ static int efi_pstore_callback(efi_char16_t *name, efi_guid_t vendor,
 			       unsigned long name_size, void *data)
 {
 	struct efivar_entry *entry;
-	int ret;
 
 	entry = kzalloc(sizeof(*entry), GFP_KERNEL);
 	if (!entry)
@@ -373,11 +372,9 @@ static int efi_pstore_callback(efi_char16_t *name, efi_guid_t vendor,
 	memcpy(entry->var.VariableName, name, name_size);
 	entry->var.VendorGuid = vendor;
 
-	ret = efivar_entry_add(entry, &efi_pstore_list);
-	if (ret)
-		kfree(entry);
+	__efivar_entry_add(entry, &efi_pstore_list);
 
-	return ret;
+	return 0;
 }
 
 static int efi_pstore_update_entry(efi_char16_t *name, efi_guid_t vendor,
diff --git a/drivers/firmware/efi/efivars.c b/drivers/firmware/efi/efivars.c
index ea0bc39dc965..c19db0b35c0d 100644
--- a/drivers/firmware/efi/efivars.c
+++ b/drivers/firmware/efi/efivars.c
@@ -527,10 +527,7 @@ efivar_create_sysfs_entry(struct efivar_entry *new_var)
 	}
 
 	kobject_uevent(&new_var->kobj, KOBJ_ADD);
-	if (efivar_entry_add(new_var, &efivar_sysfs_list)) {
-		efivar_unregister(new_var);
-		return -EINTR;
-	}
+	__efivar_entry_add(new_var, &efivar_sysfs_list);
 
 	return 0;
 }
diff --git a/drivers/firmware/efi/vars.c b/drivers/firmware/efi/vars.c
index cae590bd08f2..146360e2f1cb 100644
--- a/drivers/firmware/efi/vars.c
+++ b/drivers/firmware/efi/vars.c
@@ -450,9 +450,6 @@ int efivar_init(int (*func)(efi_char16_t *, efi_guid_t, unsigned long, void *),
 						&vendor_guid);
 		switch (status) {
 		case EFI_SUCCESS:
-			if (duplicates)
-				up(&efivars_lock);
-
 			variable_name_size = var_name_strnsize(variable_name,
 							       variable_name_size);
 
@@ -476,14 +473,6 @@ int efivar_init(int (*func)(efi_char16_t *, efi_guid_t, unsigned long, void *),
 				if (err)
 					status = EFI_NOT_FOUND;
 			}
-
-			if (duplicates) {
-				if (down_interruptible(&efivars_lock)) {
-					err = -EINTR;
-					goto free;
-				}
-			}
-
 			break;
 		case EFI_UNSUPPORTED:
 			err = -EOPNOTSUPP;
@@ -526,6 +515,17 @@ int efivar_entry_add(struct efivar_entry *entry, struct list_head *head)
 }
 EXPORT_SYMBOL_GPL(efivar_entry_add);
 
+/**
+ * __efivar_entry_add - add entry to variable list
+ * @entry: entry to add to list
+ * @head: list head
+ */
+void __efivar_entry_add(struct efivar_entry *entry, struct list_head *head)
+{
+	list_add(&entry->list, head);
+}
+EXPORT_SYMBOL_GPL(__efivar_entry_add);
+
 /**
  * efivar_entry_remove - remove entry from variable list
  * @entry: entry to remove from list
-- 
cgit v1.2.3


From 472831d4c4b2d8eac783b256e5c829487d5310df Mon Sep 17 00:00:00 2001
From: Ard Biesheuvel <ardb@kernel.org>
Date: Mon, 20 Jun 2022 13:17:20 +0200
Subject: efi: vars: Add thin wrapper around EFI get/set variable interface

The current efivars layer is a jumble of list iterators, shadow data
structures and safe variable manipulation helpers that really belong in
the efivarfs pseudo file system once the obsolete sysfs access method to
EFI variables is removed.

So split off a minimal efivar get/set variable API that reuses the
existing efivars_lock semaphore to mediate access to the various runtime
services, primarily to ensure that performing a SetVariable() on one CPU
while another is calling GetNextVariable() in a loop to enumerate the
contents of the EFI variable store does not result in surprises.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
---
 drivers/firmware/efi/vars.c | 154 +++++++++++++++++++++++++++++++++++++++++---
 1 file changed, 144 insertions(+), 10 deletions(-)

(limited to 'drivers')

diff --git a/drivers/firmware/efi/vars.c b/drivers/firmware/efi/vars.c
index 146360e2f1cb..41c82614a4b2 100644
--- a/drivers/firmware/efi/vars.c
+++ b/drivers/firmware/efi/vars.c
@@ -298,14 +298,10 @@ efivar_variable_is_removable(efi_guid_t vendor, const char *var_name,
 }
 EXPORT_SYMBOL_GPL(efivar_variable_is_removable);
 
-static efi_status_t
-check_var_size(u32 attributes, unsigned long size)
+efi_status_t check_var_size(u32 attributes, unsigned long size)
 {
 	const struct efivar_operations *fops;
 
-	if (!__efivars)
-		return EFI_UNSUPPORTED;
-
 	fops = __efivars->ops;
 
 	if (!fops->query_variable_store)
@@ -313,15 +309,12 @@ check_var_size(u32 attributes, unsigned long size)
 
 	return fops->query_variable_store(attributes, size, false);
 }
+EXPORT_SYMBOL_NS_GPL(check_var_size, EFIVAR);
 
-static efi_status_t
-check_var_size_nonblocking(u32 attributes, unsigned long size)
+efi_status_t check_var_size_nonblocking(u32 attributes, unsigned long size)
 {
 	const struct efivar_operations *fops;
 
-	if (!__efivars)
-		return EFI_UNSUPPORTED;
-
 	fops = __efivars->ops;
 
 	if (!fops->query_variable_store)
@@ -329,6 +322,7 @@ check_var_size_nonblocking(u32 attributes, unsigned long size)
 
 	return fops->query_variable_store(attributes, size, true);
 }
+EXPORT_SYMBOL_NS_GPL(check_var_size_nonblocking, EFIVAR);
 
 static bool variable_is_present(efi_char16_t *variable_name, efi_guid_t *vendor,
 				struct list_head *head)
@@ -1220,3 +1214,143 @@ int efivar_supports_writes(void)
 	return __efivars && __efivars->ops->set_variable;
 }
 EXPORT_SYMBOL_GPL(efivar_supports_writes);
+
+/*
+ * efivar_lock() - obtain the efivar lock, wait for it if needed
+ * @return 0 on success, error code on failure
+ */
+int efivar_lock(void)
+{
+	if (down_interruptible(&efivars_lock))
+		return -EINTR;
+	if (!__efivars->ops) {
+		up(&efivars_lock);
+		return -ENODEV;
+	}
+	return 0;
+}
+EXPORT_SYMBOL_NS_GPL(efivar_lock, EFIVAR);
+
+/*
+ * efivar_lock() - obtain the efivar lock if it is free
+ * @return 0 on success, error code on failure
+ */
+int efivar_trylock(void)
+{
+	if (down_trylock(&efivars_lock))
+		 return -EBUSY;
+	if (!__efivars->ops) {
+		up(&efivars_lock);
+		return -ENODEV;
+	}
+	return 0;
+}
+EXPORT_SYMBOL_NS_GPL(efivar_trylock, EFIVAR);
+
+/*
+ * efivar_unlock() - release the efivar lock
+ */
+void efivar_unlock(void)
+{
+	up(&efivars_lock);
+}
+EXPORT_SYMBOL_NS_GPL(efivar_unlock, EFIVAR);
+
+/*
+ * efivar_get_variable() - retrieve a variable identified by name/vendor
+ *
+ * Must be called with efivars_lock held.
+ */
+efi_status_t efivar_get_variable(efi_char16_t *name, efi_guid_t *vendor,
+				 u32 *attr, unsigned long *size, void *data)
+{
+	return __efivars->ops->get_variable(name, vendor, attr, size, data);
+}
+EXPORT_SYMBOL_NS_GPL(efivar_get_variable, EFIVAR);
+
+/*
+ * efivar_get_next_variable() - enumerate the next name/vendor pair
+ *
+ * Must be called with efivars_lock held.
+ */
+efi_status_t efivar_get_next_variable(unsigned long *name_size,
+				      efi_char16_t *name, efi_guid_t *vendor)
+{
+	return __efivars->ops->get_next_variable(name_size, name, vendor);
+}
+EXPORT_SYMBOL_NS_GPL(efivar_get_next_variable, EFIVAR);
+
+/*
+ * efivar_set_variable_blocking() - local helper function for set_variable
+ *
+ * Must be called with efivars_lock held.
+ */
+static efi_status_t
+efivar_set_variable_blocking(efi_char16_t *name, efi_guid_t *vendor,
+			     u32 attr, unsigned long data_size, void *data)
+{
+	efi_status_t status;
+
+	if (data_size > 0) {
+		status = check_var_size(attr, data_size +
+					      ucs2_strsize(name, 1024));
+		if (status != EFI_SUCCESS)
+			return status;
+	}
+	return __efivars->ops->set_variable(name, vendor, attr, data_size, data);
+}
+
+/*
+ * efivar_set_variable_locked() - set a variable identified by name/vendor
+ *
+ * Must be called with efivars_lock held. If @nonblocking is set, it will use
+ * non-blocking primitives so it is guaranteed not to sleep.
+ */
+efi_status_t efivar_set_variable_locked(efi_char16_t *name, efi_guid_t *vendor,
+					u32 attr, unsigned long data_size,
+					void *data, bool nonblocking)
+{
+	efi_set_variable_t *setvar;
+	efi_status_t status;
+
+	if (!nonblocking)
+		return efivar_set_variable_blocking(name, vendor, attr,
+						    data_size, data);
+
+	/*
+	 * If no _nonblocking variant exists, the ordinary one
+	 * is assumed to be non-blocking.
+	 */
+	setvar = __efivars->ops->set_variable_nonblocking ?:
+		 __efivars->ops->set_variable;
+
+	if (data_size > 0) {
+		status = check_var_size_nonblocking(attr, data_size +
+							  ucs2_strsize(name, 1024));
+		if (status != EFI_SUCCESS)
+			return status;
+	}
+	return setvar(name, vendor, attr, data_size, data);
+}
+EXPORT_SYMBOL_NS_GPL(efivar_set_variable_locked, EFIVAR);
+
+/*
+ * efivar_set_variable() - set a variable identified by name/vendor
+ *
+ * Can be called without holding the efivars_lock. Will sleep on obtaining the
+ * lock, or on obtaining other locks that are needed in order to complete the
+ * call.
+ */
+efi_status_t efivar_set_variable(efi_char16_t *name, efi_guid_t *vendor,
+				 u32 attr, unsigned long data_size, void *data)
+{
+	efi_status_t status;
+
+	if (efivar_lock())
+		return EFI_ABORTED;
+
+	status = efivar_set_variable_blocking(name, vendor, attr, data_size, data);
+	efivar_unlock();
+	return status;
+}
+EXPORT_SYMBOL_NS_GPL(efivar_set_variable, EFIVAR);
-- 
cgit v1.2.3


From 859748255b43460685e93a1f8a40b8cdc3be02f2 Mon Sep 17 00:00:00 2001
From: Ard Biesheuvel <ardb@kernel.org>
Date: Mon, 20 Jun 2022 13:21:26 +0200
Subject: efi: pstore: Omit efivars caching EFI varstore access layer

Avoid the efivars layer and simply call the newly introduced EFI
varstore helpers instead. This simplifies the code substantially, and
also allows us to remove some hacks in the shared efivars layer that
were added for efi-pstore specifically.

In order to be able to delete the EFI variable associated with a record,
store the UTF-16 name of the variable in the pstore record's priv field.
That way, we don't have to make guesses regarding which variable the
record may have been loaded from.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
---
 drivers/firmware/efi/Kconfig      |   1 +
 drivers/firmware/efi/efi-pstore.c | 374 +++++++++-----------------------------
 drivers/firmware/efi/efivars.c    |  12 +-
 drivers/firmware/efi/vars.c       |  12 +-
 4 files changed, 91 insertions(+), 308 deletions(-)

(limited to 'drivers')

diff --git a/drivers/firmware/efi/Kconfig b/drivers/firmware/efi/Kconfig
index 6fd4414c4836..7fe8b5c686d2 100644
--- a/drivers/firmware/efi/Kconfig
+++ b/drivers/firmware/efi/Kconfig
@@ -22,6 +22,7 @@ config EFI_ESRT
 config EFI_VARS_PSTORE
 	tristate "Register efivars backend for pstore"
 	depends on PSTORE
+	select UCS2_STRING
 	default y
 	help
 	  Say Y here to enable use efivars as a backend to pstore. This
diff --git a/drivers/firmware/efi/efi-pstore.c b/drivers/firmware/efi/efi-pstore.c
index 0d80cc7ff6ca..3bddc152fcd4 100644
--- a/drivers/firmware/efi/efi-pstore.c
+++ b/drivers/firmware/efi/efi-pstore.c
@@ -6,6 +6,8 @@
 #include <linux/slab.h>
 #include <linux/ucs2_string.h>
 
+MODULE_IMPORT_NS(EFIVAR);
+
 #define DUMP_NAME_LEN 66
 
 #define EFIVARS_DATA_SIZE_MAX 1024
@@ -20,18 +22,25 @@ module_param_named(pstore_disable, efivars_pstore_disable, bool, 0644);
 	 EFI_VARIABLE_BOOTSERVICE_ACCESS | \
 	 EFI_VARIABLE_RUNTIME_ACCESS)
 
-static LIST_HEAD(efi_pstore_list);
-static DECLARE_WORK(efivar_work, NULL);
-
 static int efi_pstore_open(struct pstore_info *psi)
 {
-	psi->data = NULL;
+	int err;
+
+	err = efivar_lock();
+	if (err)
+		return err;
+
+	psi->data = kzalloc(EFIVARS_DATA_SIZE_MAX, GFP_KERNEL);
+	if (!psi->data)
+		return -ENOMEM;
+
 	return 0;
 }
 
 static int efi_pstore_close(struct pstore_info *psi)
 {
-	psi->data = NULL;
+	efivar_unlock();
+	kfree(psi->data);
 	return 0;
 }
 
@@ -40,22 +49,17 @@ static inline u64 generic_id(u64 timestamp, unsigned int part, int count)
 	return (timestamp * 100 + part) * 1000 + count;
 }
 
-static int efi_pstore_read_func(struct efivar_entry *entry,
-				struct pstore_record *record)
+static int efi_pstore_read_func(struct pstore_record *record,
+				efi_char16_t *varname)
 {
-	efi_guid_t vendor = LINUX_EFI_CRASH_GUID;
+	unsigned long wlen, size = EFIVARS_DATA_SIZE_MAX;
 	char name[DUMP_NAME_LEN], data_type;
-	int i;
+	efi_status_t status;
 	int cnt;
 	unsigned int part;
-	unsigned long size;
 	u64 time;
 
-	if (efi_guidcmp(entry->var.VendorGuid, vendor))
-		return 0;
-
-	for (i = 0; i < DUMP_NAME_LEN; i++)
-		name[i] = entry->var.VariableName[i];
+	ucs2_as_utf8(name, varname, DUMP_NAME_LEN);
 
 	if (sscanf(name, "dump-type%u-%u-%d-%llu-%c",
 		   &record->type, &part, &cnt, &time, &data_type) == 5) {
@@ -95,161 +99,75 @@ static int efi_pstore_read_func(struct efivar_entry *entry,
 	} else
 		return 0;
 
-	entry->var.DataSize = 1024;
-	__efivar_entry_get(entry, &entry->var.Attributes,
-			   &entry->var.DataSize, entry->var.Data);
-	size = entry->var.DataSize;
-	memcpy(record->buf, entry->var.Data,
-	       (size_t)min_t(unsigned long, EFIVARS_DATA_SIZE_MAX, size));
-
-	return size;
-}
-
-/**
- * efi_pstore_scan_sysfs_enter
- * @pos: scanning entry
- * @next: next entry
- * @head: list head
- */
-static void efi_pstore_scan_sysfs_enter(struct efivar_entry *pos,
-					struct efivar_entry *next,
-					struct list_head *head)
-{
-	pos->scanning = true;
-	if (&next->list != head)
-		next->scanning = true;
-}
-
-/**
- * __efi_pstore_scan_sysfs_exit
- * @entry: deleting entry
- * @turn_off_scanning: Check if a scanning flag should be turned off
- */
-static inline int __efi_pstore_scan_sysfs_exit(struct efivar_entry *entry,
-						bool turn_off_scanning)
-{
-	if (entry->deleting) {
-		list_del(&entry->list);
-		efivar_entry_iter_end();
-		kfree(entry);
-		if (efivar_entry_iter_begin())
-			return -EINTR;
-	} else if (turn_off_scanning)
-		entry->scanning = false;
-
-	return 0;
-}
-
-/**
- * efi_pstore_scan_sysfs_exit
- * @pos: scanning entry
- * @next: next entry
- * @head: list head
- * @stop: a flag checking if scanning will stop
- */
-static int efi_pstore_scan_sysfs_exit(struct efivar_entry *pos,
-				       struct efivar_entry *next,
-				       struct list_head *head, bool stop)
-{
-	int ret = __efi_pstore_scan_sysfs_exit(pos, true);
-
-	if (ret)
-		return ret;
-
-	if (stop)
-		ret = __efi_pstore_scan_sysfs_exit(next, &next->list != head);
-	return ret;
-}
+	record->buf = kmalloc(size, GFP_KERNEL);
+	if (!record->buf)
+		return -ENOMEM;
 
-/**
- * efi_pstore_sysfs_entry_iter
- *
- * @record: pstore record to pass to callback
- *
- * You MUST call efivar_entry_iter_begin() before this function, and
- * efivar_entry_iter_end() afterwards.
- *
- */
-static int efi_pstore_sysfs_entry_iter(struct pstore_record *record)
-{
-	struct efivar_entry **pos = (struct efivar_entry **)&record->psi->data;
-	struct efivar_entry *entry, *n;
-	struct list_head *head = &efi_pstore_list;
-	int size = 0;
-	int ret;
-
-	if (!*pos) {
-		list_for_each_entry_safe(entry, n, head, list) {
-			efi_pstore_scan_sysfs_enter(entry, n, head);
-
-			size = efi_pstore_read_func(entry, record);
-			ret = efi_pstore_scan_sysfs_exit(entry, n, head,
-							 size < 0);
-			if (ret)
-				return ret;
-			if (size)
-				break;
-		}
-		*pos = n;
-		return size;
+	status = efivar_get_variable(varname, &LINUX_EFI_CRASH_GUID, NULL,
+				     &size, record->buf);
+	if (status != EFI_SUCCESS) {
+		kfree(record->buf);
+		return -EIO;
 	}
 
-	list_for_each_entry_safe_from((*pos), n, head, list) {
-		efi_pstore_scan_sysfs_enter((*pos), n, head);
-
-		size = efi_pstore_read_func((*pos), record);
-		ret = efi_pstore_scan_sysfs_exit((*pos), n, head, size < 0);
-		if (ret)
-			return ret;
-		if (size)
-			break;
+	/*
+	 * Store the name of the variable in the pstore_record priv field, so
+	 * we can reuse it later if we need to delete the EFI variable from the
+	 * variable store.
+	 */
+	wlen = (ucs2_strnlen(varname, DUMP_NAME_LEN) + 1) * sizeof(efi_char16_t);
+	record->priv = kmemdup(varname, wlen, GFP_KERNEL);
+	if (!record->priv) {
+		kfree(record->buf);
+		return -ENOMEM;
 	}
-	*pos = n;
+
 	return size;
 }
 
-/**
- * efi_pstore_read
- *
- * This function returns a size of NVRAM entry logged via efi_pstore_write().
- * The meaning and behavior of efi_pstore/pstore are as below.
- *
- * size > 0: Got data of an entry logged via efi_pstore_write() successfully,
- *           and pstore filesystem will continue reading subsequent entries.
- * size == 0: Entry was not logged via efi_pstore_write(),
- *            and efi_pstore driver will continue reading subsequent entries.
- * size < 0: Failed to get data of entry logging via efi_pstore_write(),
- *           and pstore will stop reading entry.
- */
 static ssize_t efi_pstore_read(struct pstore_record *record)
 {
-	ssize_t size;
+	efi_char16_t *varname = record->psi->data;
+	efi_guid_t guid = LINUX_EFI_CRASH_GUID;
+	unsigned long varname_size;
+	efi_status_t status;
 
-	record->buf = kzalloc(EFIVARS_DATA_SIZE_MAX, GFP_KERNEL);
-	if (!record->buf)
-		return -ENOMEM;
+	for (;;) {
+		varname_size = EFIVARS_DATA_SIZE_MAX;
 
-	if (efivar_entry_iter_begin()) {
-		size = -EINTR;
-		goto out;
-	}
-	size = efi_pstore_sysfs_entry_iter(record);
-	efivar_entry_iter_end();
+		/*
+		 * If this is the first read() call in the pstore enumeration,
+		 * varname will be the empty string, and the GetNextVariable()
+		 * runtime service call will return the first EFI variable in
+		 * its own enumeration order, ignoring the guid argument.
+		 *
+		 * Subsequent calls to GetNextVariable() must pass the name and
+		 * guid values returned by the previous call, which is why we
+		 * store varname in record->psi->data. Given that we only
+		 * enumerate variables with the efi-pstore GUID, there is no
+		 * need to record the guid return value.
+		 */
+		status = efivar_get_next_variable(&varname_size, varname, &guid);
+		if (status == EFI_NOT_FOUND)
+			return 0;
 
-out:
-	if (size <= 0) {
-		kfree(record->buf);
-		record->buf = NULL;
+		if (status != EFI_SUCCESS)
+			return -EIO;
+
+		/* skip variables that don't concern us */
+		if (efi_guidcmp(guid, LINUX_EFI_CRASH_GUID))
+			continue;
+
+		return efi_pstore_read_func(record, varname);
 	}
-	return size;
 }
 
 static int efi_pstore_write(struct pstore_record *record)
 {
 	char name[DUMP_NAME_LEN];
 	efi_char16_t efi_name[DUMP_NAME_LEN];
-	efi_guid_t vendor = LINUX_EFI_CRASH_GUID;
-	int i, ret = 0;
+	efi_status_t status;
+	int i;
 
 	record->id = generic_id(record->time.tv_sec, record->part,
 				record->count);
@@ -265,88 +183,26 @@ static int efi_pstore_write(struct pstore_record *record)
 	for (i = 0; i < DUMP_NAME_LEN; i++)
 		efi_name[i] = name[i];
 
-	ret = efivar_entry_set_safe(efi_name, vendor, PSTORE_EFI_ATTRIBUTES,
-			      false, record->size, record->psi->buf);
-
-	if (record->reason == KMSG_DUMP_OOPS && try_module_get(THIS_MODULE))
-		if (!schedule_work(&efivar_work))
-			module_put(THIS_MODULE);
-
-	return ret;
+	if (efivar_trylock())
+		return -EBUSY;
+	status = efivar_set_variable_locked(efi_name, &LINUX_EFI_CRASH_GUID,
+					    PSTORE_EFI_ATTRIBUTES,
+					    record->size, record->psi->buf,
+					    true);
+	efivar_unlock();
+	return status == EFI_SUCCESS ? 0 : -EIO;
 };
 
-/*
- * Clean up an entry with the same name
- */
-static int efi_pstore_erase_func(struct efivar_entry *entry, void *data)
-{
-	efi_char16_t *efi_name = data;
-	efi_guid_t vendor = LINUX_EFI_CRASH_GUID;
-	unsigned long ucs2_len = ucs2_strlen(efi_name);
-
-	if (efi_guidcmp(entry->var.VendorGuid, vendor))
-		return 0;
-
-	if (ucs2_strncmp(entry->var.VariableName, efi_name, (size_t)ucs2_len))
-		return 0;
-
-	if (entry->scanning) {
-		/*
-		 * Skip deletion because this entry will be deleted
-		 * after scanning is completed.
-		 */
-		entry->deleting = true;
-	} else
-		list_del(&entry->list);
-
-	/* found */
-	__efivar_entry_delete(entry);
-
-	return 1;
-}
-
-static int efi_pstore_erase_name(const char *name)
-{
-	struct efivar_entry *entry = NULL;
-	efi_char16_t efi_name[DUMP_NAME_LEN];
-	int found, i;
-
-	for (i = 0; i < DUMP_NAME_LEN; i++) {
-		efi_name[i] = name[i];
-		if (name[i] == '\0')
-			break;
-	}
-
-	if (efivar_entry_iter_begin())
-		return -EINTR;
-
-	found = __efivar_entry_iter(efi_pstore_erase_func, &efi_pstore_list,
-				    efi_name, &entry);
-	efivar_entry_iter_end();
-
-	if (found && !entry->scanning)
-		kfree(entry);
-
-	return found ? 0 : -ENOENT;
-}
-
 static int efi_pstore_erase(struct pstore_record *record)
 {
-	char name[DUMP_NAME_LEN];
-	int ret;
+	efi_status_t status;
 
-	snprintf(name, sizeof(name), "dump-type%u-%u-%d-%lld",
-		 record->type, record->part, record->count,
-		 (long long)record->time.tv_sec);
-	ret = efi_pstore_erase_name(name);
-	if (ret != -ENOENT)
-		return ret;
-
-	snprintf(name, sizeof(name), "dump-type%u-%u-%lld",
-		record->type, record->part, (long long)record->time.tv_sec);
-	ret = efi_pstore_erase_name(name);
+	status = efivar_set_variable(record->priv, &LINUX_EFI_CRASH_GUID,
+				     PSTORE_EFI_ATTRIBUTES, 0, NULL);
 
-	return ret;
+	if (status != EFI_SUCCESS && status != EFI_NOT_FOUND)
+		return -EIO;
+	return 0;
 }
 
 static struct pstore_info efi_pstore_info = {
@@ -360,74 +216,14 @@ static struct pstore_info efi_pstore_info = {
 	.erase		= efi_pstore_erase,
 };
 
-static int efi_pstore_callback(efi_char16_t *name, efi_guid_t vendor,
-			       unsigned long name_size, void *data)
-{
-	struct efivar_entry *entry;
-
-	entry = kzalloc(sizeof(*entry), GFP_KERNEL);
-	if (!entry)
-		return -ENOMEM;
-
-	memcpy(entry->var.VariableName, name, name_size);
-	entry->var.VendorGuid = vendor;
-
-	__efivar_entry_add(entry, &efi_pstore_list);
-
-	return 0;
-}
-
-static int efi_pstore_update_entry(efi_char16_t *name, efi_guid_t vendor,
-				   unsigned long name_size, void *data)
-{
-	struct efivar_entry *entry = data;
-
-	if (efivar_entry_find(name, vendor, &efi_pstore_list, false))
-		return 0;
-
-	memcpy(entry->var.VariableName, name, name_size);
-	memcpy(&(entry->var.VendorGuid), &vendor, sizeof(efi_guid_t));
-
-	return 1;
-}
-
-static void efi_pstore_update_entries(struct work_struct *work)
-{
-	struct efivar_entry *entry;
-	int err;
-
-	/* Add new sysfs entries */
-	while (1) {
-		entry = kzalloc(sizeof(*entry), GFP_KERNEL);
-		if (!entry)
-			return;
-
-		err = efivar_init(efi_pstore_update_entry, entry,
-				  false, &efi_pstore_list);
-		if (!err)
-			break;
-
-		efivar_entry_add(entry, &efi_pstore_list);
-	}
-
-	kfree(entry);
-	module_put(THIS_MODULE);
-}
-
 static __init int efivars_pstore_init(void)
 {
-	int ret;
-
-	if (!efivars_kobject() || !efivar_supports_writes())
+	if (!efivar_supports_writes())
 		return 0;
 
 	if (efivars_pstore_disable)
 		return 0;
 
-	ret = efivar_init(efi_pstore_callback, NULL, true, &efi_pstore_list);
-	if (ret)
-		return ret;
-
 	efi_pstore_info.buf = kmalloc(4096, GFP_KERNEL);
 	if (!efi_pstore_info.buf)
 		return -ENOMEM;
@@ -440,8 +236,6 @@ static __init int efivars_pstore_init(void)
 		efi_pstore_info.bufsize = 0;
 	}
 
-	INIT_WORK(&efivar_work, efi_pstore_update_entries);
-
 	return 0;
 }
 
diff --git a/drivers/firmware/efi/efivars.c b/drivers/firmware/efi/efivars.c
index c19db0b35c0d..8341fb15f62e 100644
--- a/drivers/firmware/efi/efivars.c
+++ b/drivers/firmware/efi/efivars.c
@@ -467,16 +467,12 @@ static ssize_t efivar_delete(struct file *filp, struct kobject *kobj,
 	else if (__efivar_entry_delete(entry))
 		err = -EIO;
 
-	if (err) {
-		efivar_entry_iter_end();
+	efivar_entry_iter_end();
+
+	if (err)
 		return err;
-	}
 
-	if (!entry->scanning) {
-		efivar_entry_iter_end();
-		efivar_unregister(entry);
-	} else
-		efivar_entry_iter_end();
+	efivar_unregister(entry);
 
 	/* It's dead Jim.... */
 	return count;
diff --git a/drivers/firmware/efi/vars.c b/drivers/firmware/efi/vars.c
index 41c82614a4b2..5640ffa81544 100644
--- a/drivers/firmware/efi/vars.c
+++ b/drivers/firmware/efi/vars.c
@@ -821,16 +821,8 @@ struct efivar_entry *efivar_entry_find(efi_char16_t *name, efi_guid_t guid,
 	if (!found)
 		return NULL;
 
-	if (remove) {
-		if (entry->scanning) {
-			/*
-			 * The entry will be deleted
-			 * after scanning is completed.
-			 */
-			entry->deleting = true;
-		} else
-			list_del(&entry->list);
-	}
+	if (remove)
+		list_del(&entry->list);
 
 	return entry;
 }
-- 
cgit v1.2.3


From 3a75f9f2f9ad19bb9a0f566373ae91d8f09db85e Mon Sep 17 00:00:00 2001
From: Ard Biesheuvel <ardb@kernel.org>
Date: Tue, 21 Jun 2022 15:48:29 +0200
Subject: efi: vars: Use locking version to iterate over efivars linked lists

Both efivars and efivarfs uses __efivar_entry_iter() to go over the
linked list that shadows the list of EFI variables held by the firmware,
but fail to call the begin/end helpers that are documented as a
prerequisite.

So switch to the proper version, which is efivar_entry_iter(). Given
that in both cases, efivar_entry_remove() is invoked with the lock held
already, don't take the lock there anymore.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
---
 drivers/firmware/efi/efivars.c | 8 ++------
 drivers/firmware/efi/vars.c    | 9 +--------
 2 files changed, 3 insertions(+), 14 deletions(-)

(limited to 'drivers')

diff --git a/drivers/firmware/efi/efivars.c b/drivers/firmware/efi/efivars.c
index 8341fb15f62e..801a65582172 100644
--- a/drivers/firmware/efi/efivars.c
+++ b/drivers/firmware/efi/efivars.c
@@ -602,10 +602,7 @@ static int efivars_sysfs_callback(efi_char16_t *name, efi_guid_t vendor,
 
 static int efivar_sysfs_destroy(struct efivar_entry *entry, void *data)
 {
-	int err = efivar_entry_remove(entry);
-
-	if (err)
-		return err;
+	efivar_entry_remove(entry);
 	efivar_unregister(entry);
 	return 0;
 }
@@ -615,8 +612,7 @@ static void efivars_sysfs_exit(void)
 	/* Remove all entries and destroy */
 	int err;
 
-	err = __efivar_entry_iter(efivar_sysfs_destroy, &efivar_sysfs_list,
-				  NULL, NULL);
+	err = efivar_entry_iter(efivar_sysfs_destroy, &efivar_sysfs_list, NULL);
 	if (err) {
 		pr_err("efivars: Failed to destroy sysfs entries\n");
 		return;
diff --git a/drivers/firmware/efi/vars.c b/drivers/firmware/efi/vars.c
index 5640ffa81544..29540013b358 100644
--- a/drivers/firmware/efi/vars.c
+++ b/drivers/firmware/efi/vars.c
@@ -523,17 +523,10 @@ EXPORT_SYMBOL_GPL(__efivar_entry_add);
 /**
  * efivar_entry_remove - remove entry from variable list
  * @entry: entry to remove from list
- *
- * Returns 0 on success, or a kernel error code on failure.
  */
-int efivar_entry_remove(struct efivar_entry *entry)
+void efivar_entry_remove(struct efivar_entry *entry)
 {
-	if (down_interruptible(&efivars_lock))
-		return -EINTR;
 	list_del(&entry->list);
-	up(&efivars_lock);
-
-	return 0;
 }
 EXPORT_SYMBOL_GPL(efivar_entry_remove);
 
-- 
cgit v1.2.3


From 5ac941367a6f85777ef34ec15d60e17ea8e446d4 Mon Sep 17 00:00:00 2001
From: Ard Biesheuvel <ardb@kernel.org>
Date: Tue, 21 Jun 2022 15:54:53 +0200
Subject: efi: vars: Drop __efivar_entry_iter() helper which is no longer used

__efivar_entry_iter() uses a list iterator in a dubious way, i.e., it
assumes that the iteration variable always points to an object of the
appropriate type, even if the list traversal exhausts the list
completely, in which case it will point somewhere in the vicinity of the
list's anchor instead.

Fortunately, we no longer use this function so we can just get rid of it
entirely.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
---
 drivers/firmware/efi/vars.c | 61 ++++++---------------------------------------
 1 file changed, 7 insertions(+), 54 deletions(-)

(limited to 'drivers')

diff --git a/drivers/firmware/efi/vars.c b/drivers/firmware/efi/vars.c
index 29540013b358..932435945c85 100644
--- a/drivers/firmware/efi/vars.c
+++ b/drivers/firmware/efi/vars.c
@@ -1034,59 +1034,6 @@ void efivar_entry_iter_end(void)
 }
 EXPORT_SYMBOL_GPL(efivar_entry_iter_end);
 
-/**
- * __efivar_entry_iter - iterate over variable list
- * @func: callback function
- * @head: head of the variable list
- * @data: function-specific data to pass to callback
- * @prev: entry to begin iterating from
- *
- * Iterate over the list of EFI variables and call @func with every
- * entry on the list. It is safe for @func to remove entries in the
- * list via efivar_entry_delete().
- *
- * You MUST call efivar_entry_iter_begin() before this function, and
- * efivar_entry_iter_end() afterwards.
- *
- * It is possible to begin iteration from an arbitrary entry within
- * the list by passing @prev. @prev is updated on return to point to
- * the last entry passed to @func. To begin iterating from the
- * beginning of the list @prev must be %NULL.
- *
- * The restrictions for @func are the same as documented for
- * efivar_entry_iter().
- */
-int __efivar_entry_iter(int (*func)(struct efivar_entry *, void *),
-			struct list_head *head, void *data,
-			struct efivar_entry **prev)
-{
-	struct efivar_entry *entry, *n;
-	int err = 0;
-
-	if (!prev || !*prev) {
-		list_for_each_entry_safe(entry, n, head, list) {
-			err = func(entry, data);
-			if (err)
-				break;
-		}
-
-		if (prev)
-			*prev = entry;
-
-		return err;
-	}
-
-
-	list_for_each_entry_safe_continue((*prev), n, head, list) {
-		err = func(*prev, data);
-		if (err)
-			break;
-	}
-
-	return err;
-}
-EXPORT_SYMBOL_GPL(__efivar_entry_iter);
-
 /**
  * efivar_entry_iter - iterate over variable list
  * @func: callback function
@@ -1104,12 +1051,18 @@ EXPORT_SYMBOL_GPL(__efivar_entry_iter);
 int efivar_entry_iter(int (*func)(struct efivar_entry *, void *),
 		      struct list_head *head, void *data)
 {
+	struct efivar_entry *entry, *n;
 	int err = 0;
 
 	err = efivar_entry_iter_begin();
 	if (err)
 		return err;
-	err = __efivar_entry_iter(func, head, data, NULL);
+
+	list_for_each_entry_safe(entry, n, head, list) {
+		err = func(entry, data);
+		if (err)
+			break;
+	}
 	efivar_entry_iter_end();
 
 	return err;
-- 
cgit v1.2.3


From 1df4d1724baafa55e9803414ebcdf1ca702bc958 Mon Sep 17 00:00:00 2001
From: Zheng Zhi Yuan <kevinjone25@g.ncu.edu.tw>
Date: Sun, 26 Jun 2022 22:29:58 +0800
Subject: drivers: fix typo in firmware/efi/memmap.c

This patch fixes the spelling error in firmware/efi/memmap.c, changing
it to the correct word.

Signed-off-by: Zheng Zhi Yuan <kevinjone25@g.ncu.edu.tw>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
---
 drivers/firmware/efi/memmap.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

(limited to 'drivers')

diff --git a/drivers/firmware/efi/memmap.c b/drivers/firmware/efi/memmap.c
index cf87dd7bbd25..6ec7970dbd40 100644
--- a/drivers/firmware/efi/memmap.c
+++ b/drivers/firmware/efi/memmap.c
@@ -244,7 +244,7 @@ int __init efi_memmap_install(struct efi_memory_map_data *data)
  * @range: Address range (start, end) to split around
  *
  * Returns the number of additional EFI memmap entries required to
- * accomodate @range.
+ * accommodate @range.
  */
 int __init efi_memmap_split_count(efi_memory_desc_t *md, struct range *range)
 {
-- 
cgit v1.2.3


From 353efd5e97a7973d78f2634274b57309d0966e29 Mon Sep 17 00:00:00 2001
From: Sudeep Holla <sudeep.holla@arm.com>
Date: Tue, 28 Jun 2022 13:53:43 +0100
Subject: ACPI: PRM: Change handler_addr type to void pointer

handler_addr is a virtual address passed to efi_call_virt_pointer.
While x86 currently type cast it into the pointer in it's arch specific
arch_efi_call_virt() implementation, ARM64 is restrictive for right
reasons.

Convert the handler_addr type from u64 to void pointer.

Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
---
 drivers/acpi/prmt.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

(limited to 'drivers')

diff --git a/drivers/acpi/prmt.c b/drivers/acpi/prmt.c
index 4d3a219c67f8..998101cf16e4 100644
--- a/drivers/acpi/prmt.c
+++ b/drivers/acpi/prmt.c
@@ -53,7 +53,7 @@ static LIST_HEAD(prm_module_list);
 
 struct prm_handler_info {
 	guid_t guid;
-	u64 handler_addr;
+	void *handler_addr;
 	u64 static_data_buffer_addr;
 	u64 acpi_param_buffer_addr;
 
@@ -148,7 +148,7 @@ acpi_parse_prmt(union acpi_subtable_headers *header, const unsigned long end)
 		th = &tm->handlers[cur_handler];
 
 		guid_copy(&th->guid, (guid_t *)handler_info->handler_guid);
-		th->handler_addr = efi_pa_va_lookup(handler_info->handler_address);
+		th->handler_addr = (void *)efi_pa_va_lookup(handler_info->handler_address);
 		th->static_data_buffer_addr = efi_pa_va_lookup(handler_info->static_data_buffer_address);
 		th->acpi_param_buffer_addr = efi_pa_va_lookup(handler_info->acpi_param_buffer_address);
 	} while (++cur_handler < tm->handler_count && (handler_info = get_next_handler(handler_info)));
-- 
cgit v1.2.3


From 36d1f098e674f90b010d6eaa60e3f22f7a6aaf96 Mon Sep 17 00:00:00 2001
From: Sudeep Holla <sudeep.holla@arm.com>
Date: Tue, 28 Jun 2022 13:53:45 +0100
Subject: ACPI: Enable Platform Runtime Mechanism(PRM) support on ARM64

There is interest to make use of PRM(Platform Runtime Mechanism) even on
ARM64 ACPI platforms. Allow PRM to be enabled on ARM64 platforms. It will
be enabled by default as on x86_64.

Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
---
 drivers/acpi/Kconfig | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

(limited to 'drivers')

diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig
index 1e34f846508f..d08b7408f0a5 100644
--- a/drivers/acpi/Kconfig
+++ b/drivers/acpi/Kconfig
@@ -592,7 +592,7 @@ config X86_PM_TIMER
 
 config ACPI_PRMT
 	bool "Platform Runtime Mechanism Support"
-	depends on EFI && X86_64
+	depends on EFI && (X86_64 || ARM64)
 	default y
 	help
 	  Platform Runtime Mechanism (PRM) is a firmware interface exposing a
-- 
cgit v1.2.3


From e3435fff6ae03ca3ec1279299664f968478067e2 Mon Sep 17 00:00:00 2001
From: Sudeep Holla <sudeep.holla@arm.com>
Date: Tue, 28 Jun 2022 13:53:46 +0100
Subject: ACPI: Move PRM config option under the main ACPI config

Currently PRM(Platform Runtime Mechanism) config option is listed along
with the main ACPI (Advanced Configuration and Power Interface) option
at the same level. On ARM64 platforms unlike x86, ACPI option is listed
at the topmost level of configuration menu. It is rather very confusing
to see PRM option also listed along with ACPI in the topmost level.

Move the same under ACPI config option. No functional change, just changes
the level of visibility of this option under the configuration menu.

Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
---
 drivers/acpi/Kconfig | 30 +++++++++++++++---------------
 1 file changed, 15 insertions(+), 15 deletions(-)

(limited to 'drivers')

diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig
index d08b7408f0a5..218b5b59df31 100644
--- a/drivers/acpi/Kconfig
+++ b/drivers/acpi/Kconfig
@@ -572,6 +572,21 @@ source "drivers/acpi/pmic/Kconfig"
 config ACPI_VIOT
 	bool
 
+config ACPI_PRMT
+	bool "Platform Runtime Mechanism Support"
+	depends on EFI && (X86_64 || ARM64)
+	default y
+	help
+	  Platform Runtime Mechanism (PRM) is a firmware interface exposing a
+	  set of binary executables that can be called from the AML interpreter
+	  or directly from device drivers.
+
+	  Say Y to enable the AML interpreter to execute the PRM code.
+
+	  While this feature is optional in principle, leaving it out may
+	  substantially increase computational overhead related to the
+	  initialization of some server systems.
+
 endif	# ACPI
 
 config X86_PM_TIMER
@@ -589,18 +604,3 @@ config X86_PM_TIMER
 
 	  You should nearly always say Y here because many modern
 	  systems require this timer.
-
-config ACPI_PRMT
-	bool "Platform Runtime Mechanism Support"
-	depends on EFI && (X86_64 || ARM64)
-	default y
-	help
-	  Platform Runtime Mechanism (PRM) is a firmware interface exposing a
-	  set of binary executables that can be called from the AML interpreter
-	  or directly from device drivers.
-
-	  Say Y to enable the AML interpreter to execute the PRM code.
-
-	  While this feature is optional in principle, leaving it out may
-	  substantially increase computational overhead related to the
-	  initialization of some server systems.
-- 
cgit v1.2.3