int (*d_delete)(struct dentry *);
void (*d_release)(struct dentry *);
void (*d_iput)(struct dentry *, struct inode *);
+ char *(*d_dname)((struct dentry *dentry, char *buffer, int buflen);
locking rules:
none have BKL
d_delete: yes no yes no
d_release: no no no yes
d_iput: no no no yes
+d_dname: no no no no
--------------------------- inode_operations ---------------------------
prototypes:
locking rules:
all may block, none have BKL
- i_sem(inode)
+ i_mutex(inode)
lookup: yes
create: yes
link: yes (both)
getxattr: no
listxattr: no
removexattr: yes
- Additionally, ->rmdir(), ->unlink() and ->rename() have ->i_sem on
+ Additionally, ->rmdir(), ->unlink() and ->rename() have ->i_mutex on
victim.
cross-directory ->rename() has (per-superblock) ->s_vfs_rename_sem.
->truncate() is never called directly - it's a callback, not a
prototypes:
struct inode *(*alloc_inode)(struct super_block *sb);
void (*destroy_inode)(struct inode *);
- void (*read_inode) (struct inode *);
void (*dirty_inode) (struct inode *);
int (*write_inode) (struct inode *, int);
- void (*put_inode) (struct inode *);
void (*drop_inode) (struct inode *);
void (*delete_inode) (struct inode *);
void (*put_super) (struct super_block *);
BKL s_lock s_umount
alloc_inode: no no no
destroy_inode: no
-read_inode: no (see below)
dirty_inode: no (must not sleep)
write_inode: no
-put_inode: no
drop_inode: no !!!inode_lock!!!
delete_inode: no
put_super: yes yes no
quota_read: no no no (see below)
quota_write: no no no (see below)
-->read_inode() is not a method - it's a callback used in iget().
->remount_fs() will have the s_umount lock if it's already mounted.
When called from get_sb_single, it does NOT have the s_umount lock.
->quota_read() and ->quota_write() functions are both guaranteed to
locking rules:
All except set_page_dirty may block
- BKL PageLocked(page)
+ BKL PageLocked(page) i_sem
writepage: no yes, unlocks (see below)
readpage: no yes, unlocks
sync_page: no maybe
writepages: no
set_page_dirty no no
readpages: no
-prepare_write: no yes
-commit_write: no yes
+prepare_write: no yes yes
+commit_write: no yes yes
+write_begin: no locks the page yes
+write_end: no yes, unlocks yes
+perform_write: no n/a yes
bmap: yes
invalidatepage: no yes
releasepage: no yes
redirty_page_for_writepage(), then unlock the page and return zero.
This may also be done to avoid internal deadlocks, but rarely.
-If the filesytem is called for sync then it must wait on any
+If the filesystem is called for sync then it must wait on any
in-progress I/O and then start new I/O.
The filesystem should unlock the page synchronously, before returning to the
->read on directories probably must go away - we should just enforce -EISDIR
in sys_read() and friends.
-->fsync() has i_sem on inode.
+->fsync() has i_mutex on inode.
--------------------------- dquot_operations -------------------------------
prototypes:
prototypes:
void (*open)(struct vm_area_struct*);
void (*close)(struct vm_area_struct*);
- struct page *(*nopage)(struct vm_area_struct*, unsigned long, int *);
+ int (*fault)(struct vm_area_struct*, struct vm_fault *);
+ int (*page_mkwrite)(struct vm_area_struct *, struct page *);
+ int (*access)(struct vm_area_struct *, unsigned long, void*, int, int);
locking rules:
- BKL mmap_sem
+ BKL mmap_sem PageLocked(page)
open: no yes
close: no yes
-nopage: no yes
+fault: no yes
+page_mkwrite: no yes no
+access: no yes
+
+ ->page_mkwrite() is called when a previously read-only page is
+about to become writeable. The file system is responsible for
+protecting against truncate races. Once appropriate action has been
+taking to lock out truncate, the page range should be verified to be
+within i_size. The page mapping should also be checked that it is not
+NULL.
+
+ ->access() is called when get_user_pages() fails in
+acces_process_vm(), typically used to debug a process through
+/proc/pid/mem or ptrace. This function is needed only for
+VM_IO | VM_PFNMAP VMAs.
================================================================================
Dubious stuff
ipc/shm.c::shm_delete() - may need BKL.
->read() and ->write() in many drivers are (probably) missing BKL.
-drivers/sgi/char/graphics.c::sgi_graphics_nopage() - may need BKL.