fs/ubifs/file.c

File Facts

System

Linux kernel

Corpus path

fs/ubifs/file.c

Extension

.c

Size

48450 bytes

Lines

1667

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

• ubifs.h
• linux/mount.h
• linux/slab.h
• linux/migrate.h

Detected Declarations

• function Copyright
• function do_readpage
• function release_new_page_budget
• function release_existing_page_budget
• function write_begin_slow
• function allocate_budget
• function ubifs_write_begin
• function cancel_budget
• function ubifs_write_end
• function populate_page
• function ubifs_do_bulk_read
• function ubifs_bulk_read
• function ubifs_read_folio
• function do_writepage
• function XXX
• function ubifs_writepages
• function do_attr_changes
• function do_truncation
• function do_setattr
• function ubifs_setattr
• function ubifs_invalidate_folio
• function ubifs_fsync
• function mctime_update_needed
• function ubifs_update_time
• function update_mctime
• function ubifs_write_iter
• function ubifs_dirty_folio
• function ubifs_release_folio
• function mmap
• function folio_pos
• function ubifs_file_mmap_prepare
• function ubifs_symlink_getattr

Annotated Snippet

const struct file_operations ubifs_file_operations = {
	.llseek         = generic_file_llseek,
	.read_iter      = generic_file_read_iter,
	.write_iter     = ubifs_write_iter,
	.mmap_prepare   = ubifs_file_mmap_prepare,
	.fsync          = ubifs_fsync,
	.unlocked_ioctl = ubifs_ioctl,
	.splice_read	= filemap_splice_read,
	.splice_write	= iter_file_splice_write,
	.open		= fscrypt_file_open,
#ifdef CONFIG_COMPAT
	.compat_ioctl   = ubifs_compat_ioctl,
#endif
};

Annotation

• Immediate include surface: `ubifs.h`, `linux/mount.h`, `linux/slab.h`, `linux/migrate.h`.
• Detected declarations: `function Copyright`, `function do_readpage`, `function release_new_page_budget`, `function release_existing_page_budget`, `function write_begin_slow`, `function allocate_budget`, `function ubifs_write_begin`, `function cancel_budget`, `function ubifs_write_end`, `function populate_page`.
• 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.