fs/inode.c
Source file repositories/reference/linux-study-clean/fs/inode.c
File Facts
- System
- Linux kernel
- Corpus path
fs/inode.c- Extension
.c- Size
- 87512 bytes
- Lines
- 3124
- Domain
- Core OS
- Bucket
- VFS And Filesystem Core
- Inferred role
- Core OS: operation-table or driver-model contract
- Status
- pattern implementation candidate
Why This File Exists
Core operating-system implementation surface: boot, tasks, memory, VFS, syscall-facing interfaces, synchronization, credentials, and isolation.
- Core operating-system implementation surface: boot, tasks, memory, VFS, syscall-facing interfaces, synchronization, credentials, and isolation.
- Defines an operation table; this is where Linux turns generic core objects into subsystem-specific behavior.
- Uses kernel synchronization; read lock ordering, sleepability, and interrupt context assumptions before translating.
- Allocates kernel memory; connect allocation flags and lifetime to context constraints.
- Defines or uses C structs; map object ownership, embedded links, reference counts, and lock ownership.
Dependency Surface
linux/export.hlinux/fs.hlinux/filelock.hlinux/mm.hlinux/backing-dev.hlinux/hash.hlinux/swap.hlinux/security.hlinux/cdev.hlinux/memblock.hlinux/fsnotify.hlinux/fsverity.hlinux/mount.hlinux/posix_acl.hlinux/ratelimit.hlinux/list_lru.hlinux/iversion.hlinux/rw_hint.hlinux/seq_file.hlinux/debugfs.htrace/events/writeback.htrace/events/timestamp.hinternal.h
Detected Declarations
function get_nr_inodesfunction get_nr_inodes_unusedfunction get_nr_dirty_inodesfunction get_mg_ctime_updatesfunction get_mg_fine_stampsfunction get_mg_ctime_swapsfunction mgts_showfunction mg_debugfs_initfunction proc_nr_inodesfunction init_fs_inode_sysctlsfunction no_openfunction inode_init_always_gfpfunction free_inode_nonrcufunction i_callbackfunction __destroy_inodefunction destroy_inodefunction drop_nlinkfunction drop_nlinkfunction set_nlinkfunction dec_nlinkfunction __address_space_init_oncefunction address_space_init_oncefunction inode_init_oncefunction init_oncefunction wait_on_new_inodefunction __inode_lru_list_addfunction neededfunction inode_lru_list_delfunction inode_pin_lru_isolatingfunction inode_unpin_lru_isolatingfunction inode_wait_for_lru_isolatingfunction inode_sb_list_addfunction inode_sb_list_delfunction hashfunction __insert_inode_hashfunction __remove_inode_hashfunction dump_mappingfunction get_kernel_nofaultfunction clear_inodefunction evictfunction dispose_listfunction evict_inodesfunction inode_lru_isolatefunction dispose_listfunction intfunction get_next_inofunction mapping_set_gfp_maskfunction lockdep_annotate_inode_mutex_key
Annotated Snippet
static const struct file_operations no_open_fops = {.open = no_open};
struct address_space *const mapping = &inode->i_data;
inode->i_sb = sb;
inode->i_blkbits = sb->s_blocksize_bits;
inode->i_flags = 0;
inode_state_assign_raw(inode, 0);
atomic64_set(&inode->i_sequence, 0);
atomic_set(&inode->i_count, 1);
inode->i_op = &empty_iops;
inode->i_fop = &no_open_fops;
inode->i_ino = 0;
inode->__i_nlink = 1;
inode->i_opflags = 0;
if (sb->s_xattr)
inode->i_opflags |= IOP_XATTR;
if (sb->s_type->fs_flags & FS_MGTIME)
inode->i_opflags |= IOP_MGTIME;
i_uid_write(inode, 0);
i_gid_write(inode, 0);
atomic_set(&inode->i_writecount, 0);
inode->i_size = 0;
inode->i_write_hint = WRITE_LIFE_NOT_SET;
inode->i_blocks = 0;
inode->i_bytes = 0;
inode->i_generation = 0;
inode->i_pipe = NULL;
inode->i_cdev = NULL;
inode->i_link = NULL;
inode->i_dir_seq = 0;
inode->i_rdev = 0;
inode->dirtied_when = 0;
#ifdef CONFIG_CGROUP_WRITEBACK
inode->i_wb_frn_winner = 0;
inode->i_wb_frn_avg_time = 0;
inode->i_wb_frn_history = 0;
#endif
spin_lock_init(&inode->i_lock);
lockdep_set_class(&inode->i_lock, &sb->s_type->i_lock_key);
init_rwsem(&inode->i_rwsem);
lockdep_set_class(&inode->i_rwsem, &sb->s_type->i_mutex_key);
atomic_set(&inode->i_dio_count, 0);
mapping->a_ops = &empty_aops;
mapping->host = inode;
mapping->flags = 0;
mapping->wb_err = 0;
atomic_set(&mapping->i_mmap_writable, 0);
#ifdef CONFIG_READ_ONLY_THP_FOR_FS
atomic_set(&mapping->nr_thps, 0);
#endif
mapping_set_gfp_mask(mapping, GFP_HIGHUSER_MOVABLE);
mapping->writeback_index = 0;
init_rwsem(&mapping->invalidate_lock);
lockdep_set_class_and_name(&mapping->invalidate_lock,
&sb->s_type->invalidate_lock_key,
"mapping.invalidate_lock");
if (sb->s_iflags & SB_I_STABLE_WRITES)
mapping_set_stable_writes(mapping);
inode->i_private = NULL;
inode->i_mapping = mapping;
INIT_HLIST_HEAD(&inode->i_dentry); /* buggered by rcu freeing */
#ifdef CONFIG_FS_POSIX_ACL
inode->i_acl = inode->i_default_acl = ACL_NOT_CACHED;
#endif
#ifdef CONFIG_FSNOTIFY
inode->i_fsnotify_mask = 0;
#endif
inode->i_flctx = NULL;
if (unlikely(security_inode_alloc(inode, gfp)))
return -ENOMEM;
this_cpu_inc(nr_inodes);
return 0;
}
EXPORT_SYMBOL(inode_init_always_gfp);
void free_inode_nonrcu(struct inode *inode)
{
kmem_cache_free(inode_cachep, inode);
}
EXPORT_SYMBOL(free_inode_nonrcu);
Annotation
- Immediate include surface: `linux/export.h`, `linux/fs.h`, `linux/filelock.h`, `linux/mm.h`, `linux/backing-dev.h`, `linux/hash.h`, `linux/swap.h`, `linux/security.h`.
- Detected declarations: `function get_nr_inodes`, `function get_nr_inodes_unused`, `function get_nr_dirty_inodes`, `function get_mg_ctime_updates`, `function get_mg_fine_stamps`, `function get_mg_ctime_swaps`, `function mgts_show`, `function mg_debugfs_init`, `function proc_nr_inodes`, `function init_fs_inode_sysctls`.
- Atlas domain: Core OS / VFS And Filesystem Core.
- Implementation status: pattern implementation candidate.
- Synchronization appears in or near this file; preserve lock ordering, sleepability, and interrupt-context constraints.
Implementation Notes
- This generated page is the file-by-file coverage layer; curated subsystem chapters should link here when they synthesize a multi-file control flow.
- Core OS pages should be promoted from atlas-only to deep-reviewed when they explain data structures, invariants, locking, lifecycle, and C implementation snippets.
- Driver-family pages are intentionally pattern-oriented unless they are part of the selected PCIe/NVMe representative device path.