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authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-19 10:09:22 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-19 10:09:22 -0700
commitf4cdf7ca9a1fdcca413157df19753f388a5a224e (patch)
tree60a31895b2446cd7fa27514e8c2843534a0de0da /drivers/md/dm-target.c
downloadlinux-stable-f4cdf7ca9a1fdcca413157df19753f388a5a224e.tar.gz
linux-stable-f4cdf7ca9a1fdcca413157df19753f388a5a224e.zip
Merge tag 'media/v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-mediagrafted
Pull media updates from Mauro Carvalho Chehab: - v4l2-core: added ISP statistics support and per-block validation - v4l2-core: Allow unknown HDR10 white point and luminance - New camera sensors: Sony IMX678 and IMX471m, Himax HM1092 IR sensor - New codec: Milos: VPU v2.0 codec support - isp driver: gained support for Dreamchip RPPX1 ISP framework - vsp1 driver: gained support for RZ/T2H and RZ/N2H - Novalake driver: gained CVS support for new NVL hardware - dvb-core: fix feed leak on failed DMX_ADD_PID - several driver fixes, cleanups and minor improvements * tag 'media/v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (308 commits) media: ipu-bridge: check all DMI entries when overriding sensor rotation media: v4l2-async: avoid deleting unlinked ASC entry on link error media: rzg2l-cru: Align bytesperline to hardware DMA stride requirement media: intel/ipu6: fix async notifier cleanup leak on parse error media: staging/ipu7: fix async notifier UAF on probe error path media: amd: isp4: fix self-deadlock in isp4sd_pwron_and_init() error path media: amd: isp4: release partial allocations in isp4if_alloc_fw_gpumem() media: rcar-isp: Fix VSPX reference leaks media: rcar-isp: Release ISPCORE resources media: i2c: imx415: Release runtime PM reference on VBLANK error media: i2c: imx415: Return test pattern write errors media: renesas: vsp1: Declare index variables in for loop statement media: renesas: vsp1: Make reset control optional to support platforms without a reset line media: dt-bindings: media: renesas,vsp1: Document RZ/T2H and RZ/N2H SoCs media: dt-bindings: media: renesas,fcp: Document RZ/T2H and RZ/N2H SoCs media: nxp: imx8-isi: Add additional 32-bit RGB format support media: nxp: imx8-isi: Add 16-bit raw Bayer format support media: nxp: imx8-isi: Implement per-stream reference counting for multiplexed streams media: nxp: imx8-isi: Use BIT_ULL() for 64-bit stream masks media: nxp: imx8-isi: Correct color map between V4L2 and ISI ...
Diffstat (limited to 'drivers/md/dm-target.c')
-rw-r--r--drivers/md/dm-target.c287
1 files changed, 287 insertions, 0 deletions
diff --git a/drivers/md/dm-target.c b/drivers/md/dm-target.c
new file mode 100644
index 000000000..3d294365e
--- /dev/null
+++ b/drivers/md/dm-target.c
@@ -0,0 +1,287 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2001 Sistina Software (UK) Limited
+ *
+ * This file is released under the GPL.
+ */
+
+#include "dm-core.h"
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/kmod.h>
+#include <linux/bio.h>
+#include <linux/dax.h>
+
+#define DM_MSG_PREFIX "target"
+
+static LIST_HEAD(_targets);
+static DECLARE_RWSEM(_lock);
+
+static inline struct target_type *__find_target_type(const char *name)
+{
+ struct target_type *tt;
+
+ list_for_each_entry(tt, &_targets, list)
+ if (!strcmp(name, tt->name))
+ return tt;
+
+ return NULL;
+}
+
+static struct target_type *get_target_type(const char *name)
+{
+ struct target_type *tt;
+
+ down_read(&_lock);
+
+ tt = __find_target_type(name);
+ if (tt && !try_module_get(tt->module))
+ tt = NULL;
+
+ up_read(&_lock);
+ return tt;
+}
+
+static void load_module(const char *name)
+{
+ request_module("dm-%s", name);
+}
+
+struct target_type *dm_get_target_type(const char *name)
+{
+ struct target_type *tt = get_target_type(name);
+
+ if (!tt) {
+ load_module(name);
+ tt = get_target_type(name);
+ }
+
+ return tt;
+}
+
+void dm_put_target_type(struct target_type *tt)
+{
+ down_read(&_lock);
+ module_put(tt->module);
+ up_read(&_lock);
+}
+
+int dm_target_iterate(void (*iter_func)(struct target_type *tt,
+ void *param), void *param)
+{
+ struct target_type *tt;
+
+ down_read(&_lock);
+ list_for_each_entry(tt, &_targets, list)
+ iter_func(tt, param);
+ up_read(&_lock);
+
+ return 0;
+}
+
+int dm_register_target(struct target_type *tt)
+{
+ int rv = 0;
+
+ down_write(&_lock);
+ if (__find_target_type(tt->name)) {
+ DMERR("%s: '%s' target already registered",
+ __func__, tt->name);
+ rv = -EBUSY;
+ } else {
+ list_add(&tt->list, &_targets);
+ }
+ up_write(&_lock);
+
+ return rv;
+}
+EXPORT_SYMBOL(dm_register_target);
+
+void dm_unregister_target(struct target_type *tt)
+{
+ down_write(&_lock);
+ if (!__find_target_type(tt->name)) {
+ DMCRIT("Unregistering unrecognised target: %s", tt->name);
+ BUG();
+ }
+
+ list_del(&tt->list);
+
+ up_write(&_lock);
+}
+EXPORT_SYMBOL(dm_unregister_target);
+
+/*
+ * io-err: always fails an io, useful for bringing
+ * up LVs that have holes in them.
+ */
+struct io_err_c {
+ struct dm_dev *dev;
+ sector_t start;
+};
+
+static int io_err_get_args(struct dm_target *tt, unsigned int argc, char **args)
+{
+ unsigned long long start;
+ struct io_err_c *ioec;
+ char dummy;
+ int ret;
+
+ ioec = kmalloc_obj(*ioec);
+ if (!ioec) {
+ tt->error = "Cannot allocate io_err context";
+ return -ENOMEM;
+ }
+
+ ret = -EINVAL;
+ if (sscanf(args[1], "%llu%c", &start, &dummy) != 1 ||
+ start != (sector_t)start) {
+ tt->error = "Invalid device sector";
+ goto bad;
+ }
+ ioec->start = start;
+
+ ret = dm_get_device(tt, args[0], dm_table_get_mode(tt->table), &ioec->dev);
+ if (ret) {
+ tt->error = "Device lookup failed";
+ goto bad;
+ }
+
+ tt->private = ioec;
+
+ return 0;
+
+bad:
+ kfree(ioec);
+
+ return ret;
+}
+
+static int io_err_ctr(struct dm_target *tt, unsigned int argc, char **args)
+{
+ /*
+ * If we have arguments, assume it is the path to the backing
+ * block device and its mapping start sector (same as dm-linear).
+ * In this case, get the device so that we can get its limits.
+ */
+ if (argc == 2) {
+ int ret = io_err_get_args(tt, argc, args);
+
+ if (ret)
+ return ret;
+ }
+
+ /*
+ * Return error for discards instead of -EOPNOTSUPP
+ */
+ tt->num_discard_bios = 1;
+ tt->discards_supported = true;
+
+ return 0;
+}
+
+static void io_err_dtr(struct dm_target *tt)
+{
+ struct io_err_c *ioec = tt->private;
+
+ if (ioec) {
+ dm_put_device(tt, ioec->dev);
+ kfree(ioec);
+ }
+}
+
+static int io_err_map(struct dm_target *tt, struct bio *bio)
+{
+ return DM_MAPIO_KILL;
+}
+
+static int io_err_clone_and_map_rq(struct dm_target *ti, struct request *rq,
+ union map_info *map_context,
+ struct request **clone)
+{
+ return DM_MAPIO_KILL;
+}
+
+static void io_err_release_clone_rq(struct request *clone,
+ union map_info *map_context)
+{
+}
+
+#ifdef CONFIG_BLK_DEV_ZONED
+static sector_t io_err_map_sector(struct dm_target *ti, sector_t bi_sector)
+{
+ struct io_err_c *ioec = ti->private;
+
+ return ioec->start + dm_target_offset(ti, bi_sector);
+}
+
+static int io_err_report_zones(struct dm_target *ti,
+ struct dm_report_zones_args *args, unsigned int nr_zones)
+{
+ struct io_err_c *ioec = ti->private;
+
+ /*
+ * This should never be called when we do not have a backing device
+ * as that mean the target is not a zoned one.
+ */
+ if (WARN_ON_ONCE(!ioec))
+ return -EIO;
+
+ return dm_report_zones(ioec->dev->bdev, ioec->start,
+ io_err_map_sector(ti, args->next_sector),
+ args, nr_zones);
+}
+#else
+#define io_err_report_zones NULL
+#endif
+
+static int io_err_iterate_devices(struct dm_target *ti,
+ iterate_devices_callout_fn fn, void *data)
+{
+ struct io_err_c *ioec = ti->private;
+
+ if (!ioec)
+ return 0;
+
+ return fn(ti, ioec->dev, ioec->start, ti->len, data);
+}
+
+static void io_err_io_hints(struct dm_target *ti, struct queue_limits *limits)
+{
+ limits->max_hw_discard_sectors = UINT_MAX;
+ limits->discard_granularity = 512;
+}
+
+static long io_err_dax_direct_access(struct dm_target *ti, pgoff_t pgoff,
+ long nr_pages, enum dax_access_mode mode, void **kaddr,
+ unsigned long *pfn)
+{
+ return -EIO;
+}
+
+static struct target_type error_target = {
+ .name = "error",
+ .version = {1, 7, 0},
+ .features = DM_TARGET_WILDCARD | DM_TARGET_ZONED_HM |
+ DM_TARGET_PASSES_INTEGRITY,
+ .ctr = io_err_ctr,
+ .dtr = io_err_dtr,
+ .map = io_err_map,
+ .clone_and_map_rq = io_err_clone_and_map_rq,
+ .release_clone_rq = io_err_release_clone_rq,
+ .iterate_devices = io_err_iterate_devices,
+ .io_hints = io_err_io_hints,
+ .direct_access = io_err_dax_direct_access,
+ .report_zones = io_err_report_zones,
+};
+
+int __init dm_target_init(void)
+{
+ return dm_register_target(&error_target);
+}
+
+void dm_target_exit(void)
+{
+ dm_unregister_target(&error_target);
+}