From 049b3c10eecd0a5f3605fa3cd13f638593213ccb Mon Sep 17 00:00:00 2001 From: Al Viro Date: Sat, 9 Jun 2012 11:55:20 -0400 Subject: vfs: update documentation on ->i_dentry handling we used to need to clean it in RCU callback freeing an inode; in 3.2 that requirement went away. Unfortunately, it hadn't been reflected in Documentation/filesystems/porting. Signed-off-by: Al Viro --- Documentation/filesystems/porting | 10 ++++------ 1 file changed, 4 insertions(+), 6 deletions(-) (limited to 'Documentation/filesystems') diff --git a/Documentation/filesystems/porting b/Documentation/filesystems/porting index 8c91d1057d9a..ed9fbc23ece0 100644 --- a/Documentation/filesystems/porting +++ b/Documentation/filesystems/porting @@ -355,12 +355,10 @@ protects *all* the dcache state of a given dentry. via rcu-walk path walk (basically, if the file can have had a path name in the vfs namespace). - i_dentry and i_rcu share storage in a union, and the vfs expects -i_dentry to be reinitialized before it is freed, so an: - - INIT_LIST_HEAD(&inode->i_dentry); - -must be done in the RCU callback. + Even though i_dentry and i_rcu share storage in a union, we will +initialize the former in inode_init_always(), so just leave it alone in +the callback. It used to be necessary to clean it there, but not anymore +(starting at 3.2). -- [recommended] -- cgit v1.2.3 From d18e9008c377dc6a6d2166a6840bf3a23a5867fd Mon Sep 17 00:00:00 2001 From: Miklos Szeredi Date: Tue, 5 Jun 2012 15:10:17 +0200 Subject: vfs: add i_op->atomic_open() Add a new inode operation which is called on the last component of an open. Using this the filesystem can look up, possibly create and open the file in one atomic operation. If it cannot perform this (e.g. the file type turned out to be wrong) it may signal this by returning NULL instead of an open struct file pointer. i_op->atomic_open() is only called if the last component is negative or needs lookup. Handling cached positive dentries here doesn't add much value: these can be opened using f_op->open(). If the cached file turns out to be invalid, the open can be retried, this time using ->atomic_open() with a fresh dentry. For now leave the old way of using open intents in lookup and revalidate in place. This will be removed once all the users are converted. David Howells noticed that if ->atomic_open() opens the file but does not create it, handle_truncate() will be called on it even if it is not a regular file. Fix this by checking the file type in this case too. Signed-off-by: Miklos Szeredi Signed-off-by: Al Viro --- Documentation/filesystems/Locking | 4 ++++ Documentation/filesystems/vfs.txt | 11 +++++++++++ 2 files changed, 15 insertions(+) (limited to 'Documentation/filesystems') diff --git a/Documentation/filesystems/Locking b/Documentation/filesystems/Locking index 8e2da1e06e3b..8157488c3463 100644 --- a/Documentation/filesystems/Locking +++ b/Documentation/filesystems/Locking @@ -62,6 +62,9 @@ ata *); int (*removexattr) (struct dentry *, const char *); int (*fiemap)(struct inode *, struct fiemap_extent_info *, u64 start, u64 len); void (*update_time)(struct inode *, struct timespec *, int); + struct file * (*atomic_open)(struct inode *, struct dentry *, + struct opendata *, unsigned open_flag, + umode_t create_mode, bool *created); locking rules: all may block @@ -89,6 +92,7 @@ listxattr: no removexattr: yes fiemap: no update_time: no +atomic_open: yes Additionally, ->rmdir(), ->unlink() and ->rename() have ->i_mutex on victim. diff --git a/Documentation/filesystems/vfs.txt b/Documentation/filesystems/vfs.txt index efd23f481704..beb6e691f70a 100644 --- a/Documentation/filesystems/vfs.txt +++ b/Documentation/filesystems/vfs.txt @@ -364,6 +364,9 @@ struct inode_operations { ssize_t (*listxattr) (struct dentry *, char *, size_t); int (*removexattr) (struct dentry *, const char *); void (*update_time)(struct inode *, struct timespec *, int); + struct file * (*atomic_open)(struct inode *, struct dentry *, + struct opendata *, unsigned open_flag, + umode_t create_mode, bool *created); }; Again, all methods are called without any locks being held, unless @@ -476,6 +479,14 @@ otherwise noted. an inode. If this is not defined the VFS will update the inode itself and call mark_inode_dirty_sync. + atomic_open: called on the last component of an open. Using this optional + method the filesystem can look up, possibly create and open the file in + one atomic operation. If it cannot perform this (e.g. the file type + turned out to be wrong) it may signal this by returning NULL instead of + an open struct file pointer. This method is only called if the last + component is negative or needs lookup. Cached positive dentries are + still handled by f_op->open(). + The Address Space Object ======================== -- cgit v1.2.3 From 47237687d73cbeae1dd7a133c3fc3d7239094568 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Sun, 10 Jun 2012 05:01:45 -0400 Subject: ->atomic_open() prototype change - pass int * instead of bool * ... and let finish_open() report having opened the file via that sucker. Next step: don't modify od->filp at all. [AV: FILE_CREATE was already used by cifs; Miklos' fix folded] Signed-off-by: Al Viro --- Documentation/filesystems/Locking | 2 +- Documentation/filesystems/vfs.txt | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) (limited to 'Documentation/filesystems') diff --git a/Documentation/filesystems/Locking b/Documentation/filesystems/Locking index 8157488c3463..af4e45bd6cfa 100644 --- a/Documentation/filesystems/Locking +++ b/Documentation/filesystems/Locking @@ -64,7 +64,7 @@ ata *); void (*update_time)(struct inode *, struct timespec *, int); struct file * (*atomic_open)(struct inode *, struct dentry *, struct opendata *, unsigned open_flag, - umode_t create_mode, bool *created); + umode_t create_mode, int *opened); locking rules: all may block diff --git a/Documentation/filesystems/vfs.txt b/Documentation/filesystems/vfs.txt index beb6e691f70a..d7121051afcd 100644 --- a/Documentation/filesystems/vfs.txt +++ b/Documentation/filesystems/vfs.txt @@ -366,7 +366,7 @@ struct inode_operations { void (*update_time)(struct inode *, struct timespec *, int); struct file * (*atomic_open)(struct inode *, struct dentry *, struct opendata *, unsigned open_flag, - umode_t create_mode, bool *created); + umode_t create_mode, int *opened); }; Again, all methods are called without any locks being held, unless -- cgit v1.2.3 From d95852777bc8ba6b3ad3397d495c5f9dd8ca8383 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Fri, 22 Jun 2012 12:39:14 +0400 Subject: make ->atomic_open() return int Change of calling conventions: old new NULL 1 file 0 ERR_PTR(-ve) -ve Caller *knows* that struct file *; no need to return it. Signed-off-by: Al Viro --- Documentation/filesystems/Locking | 2 +- Documentation/filesystems/vfs.txt | 6 +++--- 2 files changed, 4 insertions(+), 4 deletions(-) (limited to 'Documentation/filesystems') diff --git a/Documentation/filesystems/Locking b/Documentation/filesystems/Locking index af4e45bd6cfa..46a24a6ed095 100644 --- a/Documentation/filesystems/Locking +++ b/Documentation/filesystems/Locking @@ -62,7 +62,7 @@ ata *); int (*removexattr) (struct dentry *, const char *); int (*fiemap)(struct inode *, struct fiemap_extent_info *, u64 start, u64 len); void (*update_time)(struct inode *, struct timespec *, int); - struct file * (*atomic_open)(struct inode *, struct dentry *, + int (*atomic_open)(struct inode *, struct dentry *, struct opendata *, unsigned open_flag, umode_t create_mode, int *opened); diff --git a/Documentation/filesystems/vfs.txt b/Documentation/filesystems/vfs.txt index d7121051afcd..d0d690bbc4c7 100644 --- a/Documentation/filesystems/vfs.txt +++ b/Documentation/filesystems/vfs.txt @@ -364,7 +364,7 @@ struct inode_operations { ssize_t (*listxattr) (struct dentry *, char *, size_t); int (*removexattr) (struct dentry *, const char *); void (*update_time)(struct inode *, struct timespec *, int); - struct file * (*atomic_open)(struct inode *, struct dentry *, + int (*atomic_open)(struct inode *, struct dentry *, struct opendata *, unsigned open_flag, umode_t create_mode, int *opened); }; @@ -482,8 +482,8 @@ otherwise noted. atomic_open: called on the last component of an open. Using this optional method the filesystem can look up, possibly create and open the file in one atomic operation. If it cannot perform this (e.g. the file type - turned out to be wrong) it may signal this by returning NULL instead of - an open struct file pointer. This method is only called if the last + turned out to be wrong) it may signal this by returning 1 instead of + usual 0 or -ve . This method is only called if the last component is negative or needs lookup. Cached positive dentries are still handled by f_op->open(). -- cgit v1.2.3 From 30d904947459cca2beb69e0110716f5248b31f2a Mon Sep 17 00:00:00 2001 From: Al Viro Date: Fri, 22 Jun 2012 12:40:19 +0400 Subject: kill struct opendata Just pass struct file *. Methods are happier that way... There's no need to return struct file * from finish_open() now, so let it return int. Next: saner prototypes for parts in namei.c Signed-off-by: Al Viro --- Documentation/filesystems/Locking | 2 +- Documentation/filesystems/vfs.txt | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) (limited to 'Documentation/filesystems') diff --git a/Documentation/filesystems/Locking b/Documentation/filesystems/Locking index 46a24a6ed095..33e5243948f0 100644 --- a/Documentation/filesystems/Locking +++ b/Documentation/filesystems/Locking @@ -63,7 +63,7 @@ ata *); int (*fiemap)(struct inode *, struct fiemap_extent_info *, u64 start, u64 len); void (*update_time)(struct inode *, struct timespec *, int); int (*atomic_open)(struct inode *, struct dentry *, - struct opendata *, unsigned open_flag, + struct file *, unsigned open_flag, umode_t create_mode, int *opened); locking rules: diff --git a/Documentation/filesystems/vfs.txt b/Documentation/filesystems/vfs.txt index d0d690bbc4c7..279de2190365 100644 --- a/Documentation/filesystems/vfs.txt +++ b/Documentation/filesystems/vfs.txt @@ -365,7 +365,7 @@ struct inode_operations { int (*removexattr) (struct dentry *, const char *); void (*update_time)(struct inode *, struct timespec *, int); int (*atomic_open)(struct inode *, struct dentry *, - struct opendata *, unsigned open_flag, + struct file *, unsigned open_flag, umode_t create_mode, int *opened); }; -- cgit v1.2.3 From 0b728e1911cbe6e24020727c3870628b9653f32a Mon Sep 17 00:00:00 2001 From: Al Viro Date: Sun, 10 Jun 2012 16:03:43 -0400 Subject: stop passing nameidata * to ->d_revalidate() Just the lookup flags. Die, bastard, die... Signed-off-by: Al Viro --- Documentation/filesystems/Locking | 2 +- Documentation/filesystems/porting | 5 +++++ Documentation/filesystems/vfs.txt | 8 ++++---- 3 files changed, 10 insertions(+), 5 deletions(-) (limited to 'Documentation/filesystems') diff --git a/Documentation/filesystems/Locking b/Documentation/filesystems/Locking index 33e5243948f0..52a057367f6f 100644 --- a/Documentation/filesystems/Locking +++ b/Documentation/filesystems/Locking @@ -9,7 +9,7 @@ be able to use diff(1). --------------------------- dentry_operations -------------------------- prototypes: - int (*d_revalidate)(struct dentry *, struct nameidata *); + int (*d_revalidate)(struct dentry *, unsigned int); int (*d_hash)(const struct dentry *, const struct inode *, struct qstr *); int (*d_compare)(const struct dentry *, const struct inode *, diff --git a/Documentation/filesystems/porting b/Documentation/filesystems/porting index ed9fbc23ece0..56750b714d1e 100644 --- a/Documentation/filesystems/porting +++ b/Documentation/filesystems/porting @@ -431,3 +431,8 @@ release it yourself. d_alloc_root() is gone, along with a lot of bugs caused by code misusing it. Replacement: d_make_root(inode). The difference is, d_make_root() drops the reference to inode if dentry allocation fails. + +-- +[mandatory] + The witch is dead! Well, 1/3 of it, anyway. ->d_revalidate() does *not* +take struct nameidata anymore; just the flags. diff --git a/Documentation/filesystems/vfs.txt b/Documentation/filesystems/vfs.txt index 279de2190365..b9a406b2ed0f 100644 --- a/Documentation/filesystems/vfs.txt +++ b/Documentation/filesystems/vfs.txt @@ -902,7 +902,7 @@ the VFS uses a default. As of kernel 2.6.22, the following members are defined: struct dentry_operations { - int (*d_revalidate)(struct dentry *, struct nameidata *); + int (*d_revalidate)(struct dentry *, unsigned int); int (*d_hash)(const struct dentry *, const struct inode *, struct qstr *); int (*d_compare)(const struct dentry *, const struct inode *, @@ -921,11 +921,11 @@ struct dentry_operations { dcache. Most filesystems leave this as NULL, because all their dentries in the dcache are valid - d_revalidate may be called in rcu-walk mode (nd->flags & LOOKUP_RCU). + d_revalidate may be called in rcu-walk mode (flags & LOOKUP_RCU). If in rcu-walk mode, the filesystem must revalidate the dentry without blocking or storing to the dentry, d_parent and d_inode should not be - used without care (because they can go NULL), instead nd->inode should - be used. + used without care (because they can change and, in d_inode case, even + become NULL under us). If a situation is encountered that rcu-walk cannot handle, return -ECHILD and it will be called again in ref-walk mode. -- cgit v1.2.3 From 00cd8dd3bf95f2cc8435b4cac01d9995635c6d0b Mon Sep 17 00:00:00 2001 From: Al Viro Date: Sun, 10 Jun 2012 17:13:09 -0400 Subject: stop passing nameidata to ->lookup() Just the flags; only NFS cares even about that, but there are legitimate uses for such argument. And getting rid of that completely would require splitting ->lookup() into a couple of methods (at least), so let's leave that alone for now... Signed-off-by: Al Viro --- Documentation/filesystems/Locking | 3 +-- Documentation/filesystems/porting | 4 ++-- Documentation/filesystems/vfs.txt | 2 +- 3 files changed, 4 insertions(+), 5 deletions(-) (limited to 'Documentation/filesystems') diff --git a/Documentation/filesystems/Locking b/Documentation/filesystems/Locking index 52a057367f6f..33f2c8f1db81 100644 --- a/Documentation/filesystems/Locking +++ b/Documentation/filesystems/Locking @@ -38,8 +38,7 @@ d_manage: no no yes (ref-walk) maybe --------------------------- inode_operations --------------------------- prototypes: int (*create) (struct inode *,struct dentry *,umode_t, struct nameidata *); - struct dentry * (*lookup) (struct inode *,struct dentry *, struct nameid -ata *); + struct dentry * (*lookup) (struct inode *,struct dentry *, unsigned int); int (*link) (struct dentry *,struct inode *,struct dentry *); int (*unlink) (struct inode *,struct dentry *); int (*symlink) (struct inode *,struct dentry *,const char *); diff --git a/Documentation/filesystems/porting b/Documentation/filesystems/porting index 56750b714d1e..690f573928b9 100644 --- a/Documentation/filesystems/porting +++ b/Documentation/filesystems/porting @@ -434,5 +434,5 @@ d_make_root() drops the reference to inode if dentry allocation fails. -- [mandatory] - The witch is dead! Well, 1/3 of it, anyway. ->d_revalidate() does *not* -take struct nameidata anymore; just the flags. + The witch is dead! Well, 2/3 of it, anyway. ->d_revalidate() and +->lookup() do *not* take struct nameidata anymore; just the flags. diff --git a/Documentation/filesystems/vfs.txt b/Documentation/filesystems/vfs.txt index b9a406b2ed0f..ee786354946c 100644 --- a/Documentation/filesystems/vfs.txt +++ b/Documentation/filesystems/vfs.txt @@ -342,7 +342,7 @@ filesystem. As of kernel 2.6.22, the following members are defined: struct inode_operations { int (*create) (struct inode *,struct dentry *, umode_t, struct nameidata *); - struct dentry * (*lookup) (struct inode *,struct dentry *, struct nameidata *); + struct dentry * (*lookup) (struct inode *,struct dentry *, unsigned int); int (*link) (struct dentry *,struct inode *,struct dentry *); int (*unlink) (struct inode *,struct dentry *); int (*symlink) (struct inode *,struct dentry *,const char *); -- cgit v1.2.3 From ebfc3b49a7ac25920cb5be5445f602e51d2ea559 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Sun, 10 Jun 2012 18:05:36 -0400 Subject: don't pass nameidata to ->create() boolean "does it have to be exclusive?" flag is passed instead; Local filesystem should just ignore it - the object is guaranteed not to be there yet. Signed-off-by: Al Viro --- Documentation/filesystems/Locking | 2 +- Documentation/filesystems/porting | 6 ++++++ Documentation/filesystems/vfs.txt | 2 +- 3 files changed, 8 insertions(+), 2 deletions(-) (limited to 'Documentation/filesystems') diff --git a/Documentation/filesystems/Locking b/Documentation/filesystems/Locking index 33f2c8f1db81..e0cce2a5f820 100644 --- a/Documentation/filesystems/Locking +++ b/Documentation/filesystems/Locking @@ -37,7 +37,7 @@ d_manage: no no yes (ref-walk) maybe --------------------------- inode_operations --------------------------- prototypes: - int (*create) (struct inode *,struct dentry *,umode_t, struct nameidata *); + int (*create) (struct inode *,struct dentry *,umode_t, bool); struct dentry * (*lookup) (struct inode *,struct dentry *, unsigned int); int (*link) (struct dentry *,struct inode *,struct dentry *); int (*unlink) (struct inode *,struct dentry *); diff --git a/Documentation/filesystems/porting b/Documentation/filesystems/porting index 690f573928b9..2bef2b3843d1 100644 --- a/Documentation/filesystems/porting +++ b/Documentation/filesystems/porting @@ -436,3 +436,9 @@ d_make_root() drops the reference to inode if dentry allocation fails. [mandatory] The witch is dead! Well, 2/3 of it, anyway. ->d_revalidate() and ->lookup() do *not* take struct nameidata anymore; just the flags. +-- +[mandatory] + ->create() doesn't take struct nameidata *; unlike the previous +two, it gets "is it an O_EXCL or equivalent?" boolean argument. Note that +local filesystems can ignore tha argument - they are guaranteed that the +object doesn't exist. It's remote/distributed ones that might care... diff --git a/Documentation/filesystems/vfs.txt b/Documentation/filesystems/vfs.txt index ee786354946c..aa754e01464e 100644 --- a/Documentation/filesystems/vfs.txt +++ b/Documentation/filesystems/vfs.txt @@ -341,7 +341,7 @@ This describes how the VFS can manipulate an inode in your filesystem. As of kernel 2.6.22, the following members are defined: struct inode_operations { - int (*create) (struct inode *,struct dentry *, umode_t, struct nameidata *); + int (*create) (struct inode *,struct dentry *, umode_t, bool); struct dentry * (*lookup) (struct inode *,struct dentry *, unsigned int); int (*link) (struct dentry *,struct inode *,struct dentry *); int (*unlink) (struct inode *,struct dentry *); -- cgit v1.2.3 From 06fd516c1a504828780fcd81dfe21f94dec4c868 Mon Sep 17 00:00:00 2001 From: Valerie Aurora Date: Tue, 12 Jun 2012 16:20:48 +0200 Subject: Documentation: Correct s_umount state for freeze_fs/unfreeze_fs freeze_fs/unfreeze_fs ops are called with s_umount held for write, not read. Signed-off-by: Valerie Aurora Signed-off-by: Kamal Mostafa Reviewed-by: Christoph Hellwig Signed-off-by: Jan Kara Signed-off-by: Al Viro --- Documentation/filesystems/Locking | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'Documentation/filesystems') diff --git a/Documentation/filesystems/Locking b/Documentation/filesystems/Locking index e0cce2a5f820..f566b477e81f 100644 --- a/Documentation/filesystems/Locking +++ b/Documentation/filesystems/Locking @@ -138,8 +138,8 @@ evict_inode: put_super: write write_super: read sync_fs: read -freeze_fs: read -unfreeze_fs: read +freeze_fs: write +unfreeze_fs: write statfs: maybe(read) (see below) remount_fs: write umount_begin: no -- cgit v1.2.3 From 62c230bc1790923a1b35da03596a68a6c9b5b100 Mon Sep 17 00:00:00 2001 From: Mel Gorman Date: Tue, 31 Jul 2012 16:44:55 -0700 Subject: mm: add support for a filesystem to activate swap files and use direct_IO for writing swap pages Currently swapfiles are managed entirely by the core VM by using ->bmap to allocate space and write to the blocks directly. This effectively ensures that the underlying blocks are allocated and avoids the need for the swap subsystem to locate what physical blocks store offsets within a file. If the swap subsystem is to use the filesystem information to locate the blocks, it is critical that information such as block groups, block bitmaps and the block descriptor table that map the swap file were resident in memory. This patch adds address_space_operations that the VM can call when activating or deactivating swap backed by a file. int swap_activate(struct file *); int swap_deactivate(struct file *); The ->swap_activate() method is used to communicate to the file that the VM relies on it, and the address_space should take adequate measures such as reserving space in the underlying device, reserving memory for mempools and pinning information such as the block descriptor table in memory. The ->swap_deactivate() method is called on sys_swapoff() if ->swap_activate() returned success. After a successful swapfile ->swap_activate, the swapfile is marked SWP_FILE and swapper_space.a_ops will proxy to sis->swap_file->f_mappings->a_ops using ->direct_io to write swapcache pages and ->readpage to read. It is perfectly possible that direct_IO be used to read the swap pages but it is an unnecessary complication. Similarly, it is possible that ->writepage be used instead of direct_io to write the pages but filesystem developers have stated that calling writepage from the VM is undesirable for a variety of reasons and using direct_IO opens up the possibility of writing back batches of swap pages in the future. [a.p.zijlstra@chello.nl: Original patch] Signed-off-by: Mel Gorman Acked-by: Rik van Riel Cc: Christoph Hellwig Cc: David S. Miller Cc: Eric B Munson Cc: Eric Paris Cc: James Morris Cc: Mel Gorman Cc: Mike Christie Cc: Neil Brown Cc: Peter Zijlstra Cc: Sebastian Andrzej Siewior Cc: Trond Myklebust Cc: Xiaotian Feng Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- Documentation/filesystems/Locking | 13 +++++++++++++ Documentation/filesystems/vfs.txt | 12 ++++++++++++ 2 files changed, 25 insertions(+) (limited to 'Documentation/filesystems') diff --git a/Documentation/filesystems/Locking b/Documentation/filesystems/Locking index e0cce2a5f820..2db1900d7538 100644 --- a/Documentation/filesystems/Locking +++ b/Documentation/filesystems/Locking @@ -206,6 +206,8 @@ prototypes: int (*launder_page)(struct page *); int (*is_partially_uptodate)(struct page *, read_descriptor_t *, unsigned long); int (*error_remove_page)(struct address_space *, struct page *); + int (*swap_activate)(struct file *); + int (*swap_deactivate)(struct file *); locking rules: All except set_page_dirty and freepage may block @@ -229,6 +231,8 @@ migratepage: yes (both) launder_page: yes is_partially_uptodate: yes error_remove_page: yes +swap_activate: no +swap_deactivate: no ->write_begin(), ->write_end(), ->sync_page() and ->readpage() may be called from the request handler (/dev/loop). @@ -330,6 +334,15 @@ cleaned, or an error value if not. Note that in order to prevent the page getting mapped back in and redirtied, it needs to be kept locked across the entire operation. + ->swap_activate will be called with a non-zero argument on +files backing (non block device backed) swapfiles. A return value +of zero indicates success, in which case this file can be used for +backing swapspace. The swapspace operations will be proxied to the +address space operations. + + ->swap_deactivate() will be called in the sys_swapoff() +path after ->swap_activate() returned success. + ----------------------- file_lock_operations ------------------------------ prototypes: void (*fl_copy_lock)(struct file_lock *, struct file_lock *); diff --git a/Documentation/filesystems/vfs.txt b/Documentation/filesystems/vfs.txt index aa754e01464e..065aa2dc0835 100644 --- a/Documentation/filesystems/vfs.txt +++ b/Documentation/filesystems/vfs.txt @@ -592,6 +592,8 @@ struct address_space_operations { int (*migratepage) (struct page *, struct page *); int (*launder_page) (struct page *); int (*error_remove_page) (struct mapping *mapping, struct page *page); + int (*swap_activate)(struct file *); + int (*swap_deactivate)(struct file *); }; writepage: called by the VM to write a dirty page to backing store. @@ -760,6 +762,16 @@ struct address_space_operations { Setting this implies you deal with pages going away under you, unless you have them locked or reference counts increased. + swap_activate: Called when swapon is used on a file to allocate + space if necessary and pin the block lookup information in + memory. A return value of zero indicates success, + in which case this file can be used to back swapspace. The + swapspace operations will be proxied to this address space's + ->swap_{out,in} methods. + + swap_deactivate: Called during swapoff on files where swap_activate + was successful. + The File Object =============== -- cgit v1.2.3 From 068535f1fef4c90aee23eb7b9b9a71c5b72d7cd0 Mon Sep 17 00:00:00 2001 From: "J. Bruce Fields" Date: Wed, 1 Aug 2012 07:56:16 -0400 Subject: locks: remove unused lm_release_private In commit 3b6e2723f32d ("locks: prevent side-effects of locks_release_private before file_lock is initialized") we removed the last user of lm_release_private without removing the field itself. Signed-off-by: J. Bruce Fields Signed-off-by: Linus Torvalds --- Documentation/filesystems/Locking | 2 -- 1 file changed, 2 deletions(-) (limited to 'Documentation/filesystems') diff --git a/Documentation/filesystems/Locking b/Documentation/filesystems/Locking index 2db1900d7538..7f647e17830c 100644 --- a/Documentation/filesystems/Locking +++ b/Documentation/filesystems/Locking @@ -359,7 +359,6 @@ prototypes: int (*lm_compare_owner)(struct file_lock *, struct file_lock *); void (*lm_notify)(struct file_lock *); /* unblock callback */ int (*lm_grant)(struct file_lock *, struct file_lock *, int); - void (*lm_release_private)(struct file_lock *); void (*lm_break)(struct file_lock *); /* break_lease callback */ int (*lm_change)(struct file_lock **, int); @@ -368,7 +367,6 @@ locking rules: lm_compare_owner: yes no lm_notify: yes no lm_grant: no no -lm_release_private: maybe no lm_break: yes no lm_change yes no -- cgit v1.2.3 From 34e5053fbe88800f5c2c6cbc849abb5a9f390974 Mon Sep 17 00:00:00 2001 From: Artem Bityutskiy Date: Wed, 25 Jul 2012 18:12:00 +0300 Subject: Documentation: get rid of write_super The '->write_super' superblock method is gone, and this patch removes all the references to 'write_super' from various pieces of the kernel documentation. Cc: Randy Dunlap Signed-off-by: Artem Bityutskiy Signed-off-by: Al Viro --- Documentation/filesystems/Locking | 2 -- Documentation/filesystems/porting | 5 ++--- Documentation/filesystems/vfs.txt | 4 ---- 3 files changed, 2 insertions(+), 9 deletions(-) (limited to 'Documentation/filesystems') diff --git a/Documentation/filesystems/Locking b/Documentation/filesystems/Locking index 0f103e39b4f6..e540a24e5d06 100644 --- a/Documentation/filesystems/Locking +++ b/Documentation/filesystems/Locking @@ -114,7 +114,6 @@ prototypes: int (*drop_inode) (struct inode *); void (*evict_inode) (struct inode *); void (*put_super) (struct super_block *); - void (*write_super) (struct super_block *); int (*sync_fs)(struct super_block *sb, int wait); int (*freeze_fs) (struct super_block *); int (*unfreeze_fs) (struct super_block *); @@ -136,7 +135,6 @@ write_inode: drop_inode: !!!inode->i_lock!!! evict_inode: put_super: write -write_super: read sync_fs: read freeze_fs: write unfreeze_fs: write diff --git a/Documentation/filesystems/porting b/Documentation/filesystems/porting index 2bef2b3843d1..0742feebc6e2 100644 --- a/Documentation/filesystems/porting +++ b/Documentation/filesystems/porting @@ -94,9 +94,8 @@ protected. --- [mandatory] -BKL is also moved from around sb operations. ->write_super() Is now called -without BKL held. BKL should have been shifted into individual fs sb_op -functions. If you don't need it, remove it. +BKL is also moved from around sb operations. BKL should have been shifted into +individual fs sb_op functions. If you don't need it, remove it. --- [informational] diff --git a/Documentation/filesystems/vfs.txt b/Documentation/filesystems/vfs.txt index 065aa2dc0835..2ee133e030c3 100644 --- a/Documentation/filesystems/vfs.txt +++ b/Documentation/filesystems/vfs.txt @@ -216,7 +216,6 @@ struct super_operations { void (*drop_inode) (struct inode *); void (*delete_inode) (struct inode *); void (*put_super) (struct super_block *); - void (*write_super) (struct super_block *); int (*sync_fs)(struct super_block *sb, int wait); int (*freeze_fs) (struct super_block *); int (*unfreeze_fs) (struct super_block *); @@ -273,9 +272,6 @@ or bottom half). put_super: called when the VFS wishes to free the superblock (i.e. unmount). This is called with the superblock lock held - write_super: called when the VFS superblock needs to be written to - disc. This method is optional - sync_fs: called when VFS is writing out all dirty data associated with a superblock. The second parameter indicates whether the method should wait until the write out has been completed. Optional. -- cgit v1.2.3