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| author | Linus Torvalds <torvalds@linux-foundation.org> | 2026-08-23 13:28:57 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2026-08-23 13:28:57 -0700 |
| commit | 4352b8aee98005853aa63f57d6377282de17a33f (patch) | |
| tree | 27614d7a9ef05c32d089004e104364ce42324837 /fs/configfs/mount.c | |
| download | linux-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 'fs/configfs/mount.c')
| -rw-r--r-- | fs/configfs/mount.c | 179 |
1 files changed, 179 insertions, 0 deletions
diff --git a/fs/configfs/mount.c b/fs/configfs/mount.c new file mode 100644 index 000000000..4929f3431 --- /dev/null +++ b/fs/configfs/mount.c @@ -0,0 +1,179 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * mount.c - operations for initializing and mounting configfs. + * + * Based on sysfs: + * sysfs is Copyright (C) 2001, 2002, 2003 Patrick Mochel + * + * configfs Copyright (C) 2005 Oracle. All rights reserved. + */ + +#include <linux/fs.h> +#include <linux/module.h> +#include <linux/mount.h> +#include <linux/fs_context.h> +#include <linux/pagemap.h> +#include <linux/init.h> +#include <linux/slab.h> + +#include <linux/configfs.h> +#include "configfs_internal.h" + +/* Random magic number */ +#define CONFIGFS_MAGIC 0x62656570 + +static struct vfsmount *configfs_mount = NULL; +struct kmem_cache *configfs_dir_cachep; +static int configfs_mnt_count = 0; + + +static void configfs_free_inode(struct inode *inode) +{ + if (S_ISLNK(inode->i_mode)) + kfree(inode->i_link); + free_inode_nonrcu(inode); +} + +static const struct super_operations configfs_ops = { + .statfs = simple_statfs, + .drop_inode = inode_just_drop, + .free_inode = configfs_free_inode, +}; + +static struct config_group configfs_root_group = { + .cg_item = { + .ci_namebuf = "root", + .ci_name = configfs_root_group.cg_item.ci_namebuf, + }, +}; + +int configfs_is_root(struct config_item *item) +{ + return item == &configfs_root_group.cg_item; +} + +static struct configfs_dirent configfs_root = { + .s_sibling = LIST_HEAD_INIT(configfs_root.s_sibling), + .s_children = LIST_HEAD_INIT(configfs_root.s_children), + .s_element = &configfs_root_group.cg_item, + .s_type = CONFIGFS_ROOT, + .s_iattr = NULL, +}; + +static int configfs_fill_super(struct super_block *sb, struct fs_context *fc) +{ + struct inode *inode; + struct dentry *root; + + sb->s_blocksize = PAGE_SIZE; + sb->s_blocksize_bits = PAGE_SHIFT; + sb->s_magic = CONFIGFS_MAGIC; + sb->s_op = &configfs_ops; + sb->s_time_gran = 1; + + inode = configfs_new_inode(S_IFDIR | S_IRWXU | S_IRUGO | S_IXUGO, + &configfs_root, sb); + if (inode) { + inode->i_op = &configfs_root_inode_operations; + inode->i_fop = &configfs_dir_operations; + /* directory inodes start off with i_nlink == 2 (for "." entry) */ + inc_nlink(inode); + } else { + pr_debug("could not get root inode\n"); + return -ENOMEM; + } + + root = d_make_root(inode); + if (!root) { + pr_debug("%s: could not get root dentry!\n",__func__); + return -ENOMEM; + } + config_group_init(&configfs_root_group); + configfs_root_group.cg_item.ci_dentry = root; + root->d_fsdata = &configfs_root; + sb->s_root = root; + set_default_d_op(sb, &configfs_dentry_ops); /* the rest get that */ + sb->s_d_flags |= DCACHE_DONTCACHE; + return 0; +} + +static int configfs_get_tree(struct fs_context *fc) +{ + return get_tree_single(fc, configfs_fill_super); +} + +static const struct fs_context_operations configfs_context_ops = { + .get_tree = configfs_get_tree, +}; + +static int configfs_init_fs_context(struct fs_context *fc) +{ + fc->ops = &configfs_context_ops; + return 0; +} + +static struct file_system_type configfs_fs_type = { + .owner = THIS_MODULE, + .name = "configfs", + .init_fs_context = configfs_init_fs_context, + .kill_sb = kill_anon_super, +}; +MODULE_ALIAS_FS("configfs"); + +struct dentry *configfs_pin_fs(void) +{ + int err = simple_pin_fs(&configfs_fs_type, &configfs_mount, + &configfs_mnt_count); + return err ? ERR_PTR(err) : configfs_mount->mnt_root; +} + +void configfs_release_fs(void) +{ + simple_release_fs(&configfs_mount, &configfs_mnt_count); +} + + +static int __init configfs_init(void) +{ + int err = -ENOMEM; + + configfs_dir_cachep = kmem_cache_create("configfs_dir_cache", + sizeof(struct configfs_dirent), + 0, 0, NULL); + if (!configfs_dir_cachep) + goto out; + + err = sysfs_create_mount_point(kernel_kobj, "config"); + if (err) + goto out2; + + err = register_filesystem(&configfs_fs_type); + if (err) + goto out3; + + return 0; +out3: + pr_err("Unable to register filesystem!\n"); + sysfs_remove_mount_point(kernel_kobj, "config"); +out2: + kmem_cache_destroy(configfs_dir_cachep); + configfs_dir_cachep = NULL; +out: + return err; +} + +static void __exit configfs_exit(void) +{ + unregister_filesystem(&configfs_fs_type); + sysfs_remove_mount_point(kernel_kobj, "config"); + kmem_cache_destroy(configfs_dir_cachep); + configfs_dir_cachep = NULL; +} + +MODULE_AUTHOR("Oracle"); +MODULE_LICENSE("GPL"); +MODULE_VERSION("0.0.2"); +MODULE_DESCRIPTION("Simple RAM filesystem for user driven kernel subsystem configuration."); + +core_initcall(configfs_init); +module_exit(configfs_exit); |
