* Extracted file_map API out of the file cache - it's now an optional service

that can be used by file systems.
* Changed the way the file cache works: instead of reading/writing to the
  underlying device directly, it can now be used for any data source, ie.
  also network file systems.
* As a result, the former pages_io() moved to the VFS layer, and can now be
  called by a file system via {read|write}_file_io_vec_pages() (naming
  suggestions are always welcomed :-)). It now gets an FD, and uses that to
  communicate with the device (via its fs_{read|write}_pages() hooks).
* The file_cache_{read|write}() functions must now be called without holding
  an I/O relevant file system lock. That allows the file cache to prepare the
  pages without colliding with the page writer, IOW the "mayBlock" flag can
  go into the attic again (yay!).
* This also results in a much better performance when the system does I/O and
  is low on memory, as the page writer can now finally write back some pages,
  and that even without maxing out the CPU :)
* The API changes put slightly more burden on the fs_{read|write}_pages()
  hooks, but in combination with the file_map it's still pretty straight
  forward. It just will have to dispatch the call to the underlying device
  directly, usually it will just call its fs_{read|write}_pages() hooks
  via the above mentioned calls.
* Ported BFS and FAT to the new API, the latter has not been tested, though.
* Also ported the API changes to the fs_shell. I also completely removed its
  file cache level page handling - the downside is that device access is no
  longer cached (ie. depends on the host OS now), the upside is that the code
  is greatly simplified.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@22886 a95241bf-73f2-0310-859d-f6bbb57e9c96
This commit is contained in:
Axel Dörfler
2007-11-10 21:19:52 +00:00
parent 94463f5368
commit 3d268eda3d
36 changed files with 1339 additions and 2333 deletions
+18 -4
View File
@@ -96,12 +96,10 @@ typedef struct fssh_file_system_module_info {
fssh_fs_cookie cookie);
fssh_status_t (*read_pages)(fssh_fs_volume fs, fssh_fs_vnode vnode,
fssh_fs_cookie cookie, fssh_off_t pos, const fssh_iovec *vecs,
fssh_size_t count, fssh_size_t *_numBytes, bool mayBlock,
bool reenter);
fssh_size_t count, fssh_size_t *_numBytes, bool reenter);
fssh_status_t (*write_pages)(fssh_fs_volume fs, fssh_fs_vnode vnode,
fssh_fs_cookie cookie, fssh_off_t pos, const fssh_iovec *vecs,
fssh_size_t count, fssh_size_t *_numBytes, bool mayBlock,
bool reenter);
fssh_size_t count, fssh_size_t *_numBytes, bool reenter);
/* cache file access */
fssh_status_t (*get_file_map)(fssh_fs_volume fs, fssh_fs_vnode vnode,
@@ -293,6 +291,22 @@ extern fssh_status_t fssh_unremove_vnode(fssh_mount_id mountID,
fssh_vnode_id vnodeID);
extern fssh_status_t fssh_get_vnode_removed(fssh_mount_id mountID,
fssh_vnode_id vnodeID, bool* removed);
extern fssh_status_t fssh_read_pages(int fd, fssh_off_t pos,
const struct fssh_iovec *vecs, fssh_size_t count,
fssh_size_t *_numBytes, bool fsReenter);
extern fssh_status_t fssh_write_pages(int fd, fssh_off_t pos,
const struct fssh_iovec *vecs, fssh_size_t count,
fssh_size_t *_numBytes, bool fsReenter);
extern fssh_status_t fssh_read_file_io_vec_pages(int fd,
const struct fssh_file_io_vec *fileVecs,
fssh_size_t fileVecCount, const struct fssh_iovec *vecs,
fssh_size_t vecCount, uint32_t *_vecIndex,
fssh_size_t *_vecOffset, fssh_size_t *_bytes);
extern fssh_status_t fssh_write_file_io_vec_pages(int fd,
const struct fssh_file_io_vec *fileVecs,
fssh_size_t fileVecCount, const struct fssh_iovec *vecs,
fssh_size_t vecCount, uint32_t *_vecIndex,
fssh_size_t *_vecOffset, fssh_size_t *_bytes);
extern fssh_status_t fssh_notify_entry_created(fssh_mount_id device,
fssh_vnode_id directory, const char *name, fssh_vnode_id node);