| 0,0 → 1,140 |
|---|
| /* |
| * kernfs.h - pseudo filesystem decoupled from vfs locking |
| * |
| * This file is released under the GPLv2. |
| */ |
| |
| #ifndef __LINUX_KERNFS_H |
| #define __LINUX_KERNFS_H |
| |
| #include <linux/kernel.h> |
| #include <linux/err.h> |
| #include <linux/list.h> |
| #include <linux/mutex.h> |
| #include <linux/idr.h> |
| #include <linux/lockdep.h> |
| #include <linux/rbtree.h> |
| #include <linux/atomic.h> |
| #include <linux/wait.h> |
| |
| struct file; |
| struct dentry; |
| struct iattr; |
| struct seq_file; |
| struct vm_area_struct; |
| struct super_block; |
| struct file_system_type; |
| |
| struct kernfs_open_node; |
| struct kernfs_iattrs; |
| |
| enum kernfs_node_type { |
| KERNFS_DIR = 0x0001, |
| KERNFS_FILE = 0x0002, |
| KERNFS_LINK = 0x0004, |
| }; |
| |
| #define KERNFS_TYPE_MASK 0x000f |
| #define KERNFS_FLAG_MASK ~KERNFS_TYPE_MASK |
| |
| enum kernfs_node_flag { |
| KERNFS_ACTIVATED = 0x0010, |
| KERNFS_NS = 0x0020, |
| KERNFS_HAS_SEQ_SHOW = 0x0040, |
| KERNFS_HAS_MMAP = 0x0080, |
| KERNFS_LOCKDEP = 0x0100, |
| KERNFS_SUICIDAL = 0x0400, |
| KERNFS_SUICIDED = 0x0800, |
| KERNFS_EMPTY_DIR = 0x1000, |
| }; |
| |
| /* @flags for kernfs_create_root() */ |
| enum kernfs_root_flag { |
| /* |
| * kernfs_nodes are created in the deactivated state and invisible. |
| * They require explicit kernfs_activate() to become visible. This |
| * can be used to make related nodes become visible atomically |
| * after all nodes are created successfully. |
| */ |
| KERNFS_ROOT_CREATE_DEACTIVATED = 0x0001, |
| |
| /* |
| * For regular flies, if the opener has CAP_DAC_OVERRIDE, open(2) |
| * succeeds regardless of the RW permissions. sysfs had an extra |
| * layer of enforcement where open(2) fails with -EACCES regardless |
| * of CAP_DAC_OVERRIDE if the permission doesn't have the |
| * respective read or write access at all (none of S_IRUGO or |
| * S_IWUGO) or the respective operation isn't implemented. The |
| * following flag enables that behavior. |
| */ |
| KERNFS_ROOT_EXTRA_OPEN_PERM_CHECK = 0x0002, |
| }; |
| |
| /* type-specific structures for kernfs_node union members */ |
| struct kernfs_elem_dir { |
| unsigned long subdirs; |
| /* children rbtree starts here and goes through kn->rb */ |
| struct rb_root children; |
| |
| /* |
| * The kernfs hierarchy this directory belongs to. This fits |
| * better directly in kernfs_node but is here to save space. |
| */ |
| struct kernfs_root *root; |
| }; |
| |
| struct kernfs_elem_symlink { |
| struct kernfs_node *target_kn; |
| }; |
| |
| struct kernfs_elem_attr { |
| const struct kernfs_ops *ops; |
| struct kernfs_open_node *open; |
| loff_t size; |
| struct kernfs_node *notify_next; /* for kernfs_notify() */ |
| }; |
| |
| /* |
| * kernfs_node - the building block of kernfs hierarchy. Each and every |
| * kernfs node is represented by single kernfs_node. Most fields are |
| * private to kernfs and shouldn't be accessed directly by kernfs users. |
| * |
| * As long as s_count reference is held, the kernfs_node itself is |
| * accessible. Dereferencing elem or any other outer entity requires |
| * active reference. |
| */ |
| struct kernfs_node { |
| atomic_t count; |
| atomic_t active; |
| #ifdef CONFIG_DEBUG_LOCK_ALLOC |
| struct lockdep_map dep_map; |
| #endif |
| /* |
| * Use kernfs_get_parent() and kernfs_name/path() instead of |
| * accessing the following two fields directly. If the node is |
| * never moved to a different parent, it is safe to access the |
| * parent directly. |
| */ |
| struct kernfs_node *parent; |
| const char *name; |
| |
| struct rb_node rb; |
| |
| const void *ns; /* namespace tag */ |
| unsigned int hash; /* ns + name hash */ |
| union { |
| struct kernfs_elem_dir dir; |
| struct kernfs_elem_symlink symlink; |
| struct kernfs_elem_attr attr; |
| }; |
| |
| void *priv; |
| |
| unsigned short flags; |
| umode_t mode; |
| unsigned int ino; |
| struct kernfs_iattrs *iattr; |
| }; |
| |
| |
| #endif /* __LINUX_KERNFS_H */ |