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authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-23 13:28:57 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-23 13:28:57 -0700
commit4352b8aee98005853aa63f57d6377282de17a33f (patch)
tree27614d7a9ef05c32d089004e104364ce42324837 /drivers/md/dm-init.c
downloadlinux-stable-4352b8aee98005853aa63f57d6377282de17a33f.tar.gz
linux-stable-4352b8aee98005853aa63f57d6377282de17a33f.zip
Merge tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linuxgrafted
Pull I3C updates from Alexandre Belloni: "A new driver this cycle, for the AMD AXI I3C controller. There are also new features such as IBI wakeup support, SETAASA device discovery and ACPI support for the the DAA methods, meaning we can now communicate with the SPD devices on DDR5 modules. New driver: - AMD AXI I3C master controller Subsystem: - I3C Common Command Code (CCC) handling improvements, especially around GET CCCs - SETAASA device discovery support - ACPI support for all existing DAA methods like SETDASA, SETNEWDA as well as I2C devices on I3C bus - IBI-based wakeup support Drivers: - dw: SETAASA support - mipi-i3c-hci: advertise IBI wakeup capability, AMD_PT I3C controller support, PIO queue management support for HCI v1.2 - renesas: improve suspend to RAM support, add runtime PM support" * tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux: (70 commits) i3c: dw: reduce do_daa time if there's no client i3c: mipi-i3c-hci: Add support for AMD_PT I3C controller i3c: mipi-i3c-hci: Add PIO queue management support for HCI v1.2 i3c: mipi-i3c-hci: Fix missing STAT_IBI_STATUS_THLD in PIO mode i3c: dw: rename "pclk" to "apb" to match dt-binding i3c: dw: make struct dw_i3c_cmd smaller i3c: dw: use COMMAND_PORT_TRANSFER_ARG instead of hardcoding i3c: renesas: Don't register devices when ENTDAA times out i3c: master: dw-i3c-master: fix OD timing for first broadcast i3c: mipi-i3c-hci: Advertise IBI wakeup capability i3c: mipi-i3c-hci: Factor out i3c_hci_sysdev() i3c: mipi-i3c-hci-pci: Propagate I3C wakeup requirements to PCI i3c: master: Reject IBI requests from non-IBI-capable devices i3c: master: Add helper to query bus wakeup requirements i3c: master: Report wakeup events for IBIs i3c: master: Support IBI-based wakeup capability i3c: master: Fix potential UAF in i3c_device_match() i3c: master: Fix potential UAF in i3c_device_uevent() i3c: Make dev->desc locking assumptions explicit i3c: master: Fix use-after-free of master->this ...
Diffstat (limited to 'drivers/md/dm-init.c')
-rw-r--r--drivers/md/dm-init.c328
1 files changed, 328 insertions, 0 deletions
diff --git a/drivers/md/dm-init.c b/drivers/md/dm-init.c
new file mode 100644
index 000000000..c1bacba92
--- /dev/null
+++ b/drivers/md/dm-init.c
@@ -0,0 +1,328 @@
+// SPDX-License-Identifier: GPL-2.0-only
+
+/*
+ * Copyright (C) 2017 The Chromium OS Authors <chromium-os-dev@chromium.org>
+ *
+ * This file is released under the GPLv2.
+ */
+
+#include <linux/ctype.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/device-mapper.h>
+#include <linux/init.h>
+#include <linux/list.h>
+#include <linux/moduleparam.h>
+
+#define DM_MSG_PREFIX "init"
+#define DM_MAX_DEVICES 256
+#define DM_MAX_TARGETS 256
+#define DM_MAX_STR_SIZE 4096
+#define DM_MAX_WAITFOR 256
+
+static char *create;
+
+static char *waitfor[DM_MAX_WAITFOR];
+
+/*
+ * Format: dm-mod.create=<name>,<uuid>,<minor>,<flags>,<table>[,<table>+][;<name>,<uuid>,<minor>,<flags>,<table>[,<table>+]+]
+ * Table format: <start_sector> <num_sectors> <target_type> <target_args>
+ * Block devices to wait for to become available before setting up tables:
+ * dm-mod.waitfor=<device1>[,..,<deviceN>]
+ *
+ * See Documentation/admin-guide/device-mapper/dm-init.rst for dm-mod.create="..." format
+ * details.
+ */
+
+struct dm_device {
+ struct dm_ioctl dmi;
+ struct dm_target_spec *table[DM_MAX_TARGETS];
+ char *target_args_array[DM_MAX_TARGETS];
+ struct list_head list;
+};
+
+static const char * const dm_allowed_targets[] __initconst = {
+ "crypt",
+ "delay",
+ "linear",
+ "snapshot-origin",
+ "striped",
+ "verity",
+};
+
+static int __init dm_verify_target_type(const char *target)
+{
+ unsigned int i;
+
+ for (i = 0; i < ARRAY_SIZE(dm_allowed_targets); i++) {
+ if (!strcmp(dm_allowed_targets[i], target))
+ return 0;
+ }
+ return -EINVAL;
+}
+
+static void __init dm_setup_cleanup(struct list_head *devices)
+{
+ struct dm_device *dev, *tmp;
+ unsigned int i;
+
+ list_for_each_entry_safe(dev, tmp, devices, list) {
+ list_del(&dev->list);
+ for (i = 0; i < dev->dmi.target_count; i++) {
+ kfree(dev->table[i]);
+ kfree(dev->target_args_array[i]);
+ }
+ kfree(dev);
+ }
+}
+
+/**
+ * str_field_delimit - delimit a string based on a separator char.
+ * @str: the pointer to the string to delimit.
+ * @separator: char that delimits the field
+ *
+ * Find a @separator and replace it by '\0'.
+ * Remove leading and trailing spaces.
+ * Return the remainder string after the @separator.
+ */
+static char __init *str_field_delimit(char **str, char separator)
+{
+ char *s;
+
+ /* TODO: add support for escaped characters */
+ *str = skip_spaces(*str);
+ s = strchr(*str, separator);
+ /* Delimit the field and remove trailing spaces */
+ if (s)
+ *s = '\0';
+ *str = strim(*str);
+ return s ? ++s : NULL;
+}
+
+/**
+ * dm_parse_table_entry - parse a table entry
+ * @dev: device to store the parsed information.
+ * @str: the pointer to a string with the format:
+ * <start_sector> <num_sectors> <target_type> <target_args>[, ...]
+ *
+ * Return the remainder string after the table entry, i.e, after the comma which
+ * delimits the entry or NULL if reached the end of the string.
+ */
+static char __init *dm_parse_table_entry(struct dm_device *dev, char *str)
+{
+ const unsigned int n = dev->dmi.target_count - 1;
+ struct dm_target_spec *sp;
+ unsigned int i;
+ /* fields: */
+ char *field[4];
+ char *next;
+
+ field[0] = str;
+ /* Delimit first 3 fields that are separated by space */
+ for (i = 0; i < ARRAY_SIZE(field) - 1; i++) {
+ field[i + 1] = str_field_delimit(&field[i], ' ');
+ if (!field[i + 1])
+ return ERR_PTR(-EINVAL);
+ }
+ /* Delimit last field that can be terminated by comma */
+ next = str_field_delimit(&field[i], ',');
+
+ sp = kzalloc_obj(*sp);
+ if (!sp)
+ return ERR_PTR(-ENOMEM);
+ dev->table[n] = sp;
+
+ /* start_sector */
+ if (kstrtoull(field[0], 0, &sp->sector_start))
+ return ERR_PTR(-EINVAL);
+ /* num_sector */
+ if (kstrtoull(field[1], 0, &sp->length))
+ return ERR_PTR(-EINVAL);
+ /* target_type */
+ strscpy(sp->target_type, field[2], sizeof(sp->target_type));
+ if (dm_verify_target_type(sp->target_type)) {
+ DMERR("invalid type \"%s\"", sp->target_type);
+ return ERR_PTR(-EINVAL);
+ }
+ /* target_args */
+ dev->target_args_array[n] = kstrndup(field[3], DM_MAX_STR_SIZE,
+ GFP_KERNEL);
+ if (!dev->target_args_array[n])
+ return ERR_PTR(-ENOMEM);
+
+ return next;
+}
+
+/**
+ * dm_parse_table - parse "dm-mod.create=" table field
+ * @dev: device to store the parsed information.
+ * @str: the pointer to a string with the format:
+ * <table>[,<table>+]
+ */
+static int __init dm_parse_table(struct dm_device *dev, char *str)
+{
+ char *table_entry = str;
+
+ while (table_entry) {
+ DMDEBUG("parsing table \"%s\"", str);
+ if (++dev->dmi.target_count > DM_MAX_TARGETS) {
+ DMERR("too many targets %u > %d",
+ dev->dmi.target_count, DM_MAX_TARGETS);
+ return -EINVAL;
+ }
+ table_entry = dm_parse_table_entry(dev, table_entry);
+ if (IS_ERR(table_entry)) {
+ DMERR("couldn't parse table");
+ return PTR_ERR(table_entry);
+ }
+ }
+
+ return 0;
+}
+
+/**
+ * dm_parse_device_entry - parse a device entry
+ * @dev: device to store the parsed information.
+ * @str: the pointer to a string with the format:
+ * name,uuid,minor,flags,table[; ...]
+ *
+ * Return the remainder string after the table entry, i.e, after the semi-colon
+ * which delimits the entry or NULL if reached the end of the string.
+ */
+static char __init *dm_parse_device_entry(struct dm_device *dev, char *str)
+{
+ /* There are 5 fields: name,uuid,minor,flags,table; */
+ char *field[5];
+ unsigned int i;
+ char *next;
+
+ field[0] = str;
+ /* Delimit first 4 fields that are separated by comma */
+ for (i = 0; i < ARRAY_SIZE(field) - 1; i++) {
+ field[i+1] = str_field_delimit(&field[i], ',');
+ if (!field[i+1])
+ return ERR_PTR(-EINVAL);
+ }
+ /* Delimit last field that can be delimited by semi-colon */
+ next = str_field_delimit(&field[i], ';');
+
+ /* name */
+ strscpy(dev->dmi.name, field[0], sizeof(dev->dmi.name));
+ /* uuid */
+ strscpy(dev->dmi.uuid, field[1], sizeof(dev->dmi.uuid));
+ /* minor */
+ if (strlen(field[2])) {
+ if (kstrtoull(field[2], 0, &dev->dmi.dev) ||
+ dev->dmi.dev >= (1 << MINORBITS))
+ return ERR_PTR(-EINVAL);
+ dev->dmi.dev = huge_encode_dev((dev_t)dev->dmi.dev);
+ dev->dmi.flags |= DM_PERSISTENT_DEV_FLAG;
+ }
+ /* flags */
+ if (!strcmp(field[3], "ro"))
+ dev->dmi.flags |= DM_READONLY_FLAG;
+ else if (strcmp(field[3], "rw"))
+ return ERR_PTR(-EINVAL);
+ /* table */
+ if (dm_parse_table(dev, field[4]))
+ return ERR_PTR(-EINVAL);
+
+ return next;
+}
+
+/**
+ * dm_parse_devices - parse "dm-mod.create=" argument
+ * @devices: list of struct dm_device to store the parsed information.
+ * @str: the pointer to a string with the format:
+ * <device>[;<device>+]
+ */
+static int __init dm_parse_devices(struct list_head *devices, char *str)
+{
+ unsigned long ndev = 0;
+ struct dm_device *dev;
+ char *device = str;
+
+ DMDEBUG("parsing \"%s\"", str);
+ while (device) {
+ dev = kzalloc_obj(*dev);
+ if (!dev)
+ return -ENOMEM;
+ list_add_tail(&dev->list, devices);
+
+ if (++ndev > DM_MAX_DEVICES) {
+ DMERR("too many devices %lu > %d",
+ ndev, DM_MAX_DEVICES);
+ return -EINVAL;
+ }
+
+ device = dm_parse_device_entry(dev, device);
+ if (IS_ERR(device)) {
+ DMERR("couldn't parse device");
+ return PTR_ERR(device);
+ }
+ }
+
+ return 0;
+}
+
+/**
+ * dm_init_init - parse "dm-mod.create=" argument and configure drivers
+ */
+static int __init dm_init_init(void)
+{
+ struct dm_device *dev;
+ LIST_HEAD(devices);
+ char *str;
+ int i, r;
+
+ if (!create)
+ return 0;
+
+ if (strlen(create) >= DM_MAX_STR_SIZE) {
+ DMERR("Argument is too big. Limit is %d", DM_MAX_STR_SIZE);
+ return -EINVAL;
+ }
+ str = kstrndup(create, DM_MAX_STR_SIZE, GFP_KERNEL);
+ if (!str)
+ return -ENOMEM;
+
+ r = dm_parse_devices(&devices, str);
+ if (r)
+ goto out;
+
+ DMINFO("waiting for all devices to be available before creating mapped devices");
+ wait_for_device_probe();
+
+ for (i = 0; i < ARRAY_SIZE(waitfor); i++) {
+ if (waitfor[i]) {
+ dev_t dev;
+
+ DMINFO("waiting for device %s ...", waitfor[i]);
+ while (early_lookup_bdev(waitfor[i], &dev))
+ fsleep(5000);
+ }
+ }
+
+ if (waitfor[0]) {
+ wait_for_device_probe();
+ DMINFO("all devices available");
+ }
+
+ list_for_each_entry(dev, &devices, list) {
+ if (dm_early_create(&dev->dmi, dev->table,
+ dev->target_args_array))
+ break;
+ }
+out:
+ kfree(str);
+ dm_setup_cleanup(&devices);
+ return r;
+}
+
+late_initcall(dm_init_init);
+
+module_param(create, charp, 0);
+MODULE_PARM_DESC(create, "Create a mapped device in early boot");
+
+module_param_array(waitfor, charp, NULL, 0);
+MODULE_PARM_DESC(waitfor, "Devices to wait for before setting up tables");