402 lines
13 KiB
C
402 lines
13 KiB
C
/***************************************************************************
|
|
* __________ __ ___.
|
|
* Open \______ \ ____ ____ | | _\_ |__ _______ ___
|
|
* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
|
|
* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
|
|
* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
|
|
* \/ \/ \/ \/ \/
|
|
* $Id$
|
|
*
|
|
* Copyright (C) 2014 by Michael Sevakis
|
|
*
|
|
* This program is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU General Public License
|
|
* as published by the Free Software Foundation; either version 2
|
|
* of the License, or (at your option) any later version.
|
|
*
|
|
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
|
|
* KIND, either express or implied.
|
|
*
|
|
****************************************************************************/
|
|
#include "config.h"
|
|
#include "system.h"
|
|
#include "debug.h"
|
|
#include "file.h"
|
|
#include "dir.h"
|
|
#include "disk_cache.h"
|
|
#include "fileobj_mgr.h"
|
|
#include "dircache_redirect.h"
|
|
|
|
/**
|
|
* Manages file and directory streams on all volumes
|
|
*
|
|
* Intended for internal use by disk, file and directory code
|
|
*/
|
|
|
|
|
|
/* there will always be enough of these for all user handles, thus these
|
|
functions don't return failure codes */
|
|
#define MAX_FILEOBJS (MAX_OPEN_HANDLES + AUX_FILEOBJS)
|
|
|
|
/* describes the file as an image on the storage medium */
|
|
static struct fileobj_binding
|
|
{
|
|
struct file_base_binding bind; /* base info list item (first!) */
|
|
uint16_t flags; /* F(D)(O)_* bits of this file/dir */
|
|
uint16_t writers; /* number of writer streams */
|
|
struct filestr_cache cache; /* write mode shared cache */
|
|
file_size_t size; /* size of this file */
|
|
struct ll_head list; /* open streams for this file/dir */
|
|
} fobindings[MAX_FILEOBJS];
|
|
static struct mutex stream_mutexes[MAX_FILEOBJS] SHAREDBSS_ATTR;
|
|
static struct ll_head free_bindings;
|
|
static struct ll_head busy_bindings[NUM_VOLUMES];
|
|
|
|
#define BUSY_BINDINGS(volume) \
|
|
(&busy_bindings[IF_MV_VOL(volume)])
|
|
|
|
#define BASEBINDING_LIST(bindp) \
|
|
(BUSY_BINDINGS(BASEBINDING_VOL(bindp)))
|
|
|
|
#define FREE_BINDINGS() \
|
|
(&free_bindings)
|
|
|
|
#define BINDING_FIRST(type, volume...) \
|
|
((struct fileobj_binding *)type##_BINDINGS(volume)->head)
|
|
|
|
#define BINDING_NEXT(fobp) \
|
|
((struct fileobj_binding *)(fobp)->bind.node.next)
|
|
|
|
#define FOR_EACH_BINDING(volume, fobp) \
|
|
for (struct fileobj_binding *fobp = BINDING_FIRST(BUSY, volume); \
|
|
fobp; fobp = BINDING_NEXT(fobp))
|
|
|
|
#define STREAM_FIRST(fobp) \
|
|
((struct filestr_base *)(fobp)->list.head)
|
|
|
|
#define STREAM_NEXT(s) \
|
|
((struct filestr_base *)(s)->node.next)
|
|
|
|
#define STREAM_THIS(s) \
|
|
(s)
|
|
|
|
#define FOR_EACH_STREAM(what, start, s) \
|
|
for (struct filestr_base *s = STREAM_##what(start); \
|
|
s; s = STREAM_NEXT(s))
|
|
|
|
|
|
/* syncs information for the stream's old and new parent directory if any are
|
|
currently opened */
|
|
static void fileobj_sync_parent(const struct file_base_info *infop[],
|
|
int count)
|
|
{
|
|
FOR_EACH_BINDING(infop[0]->volume, fobp)
|
|
{
|
|
if ((fobp->flags & (FO_DIRECTORY|FO_REMOVED)) != FO_DIRECTORY)
|
|
continue; /* not directory or removed can't be parent of anything */
|
|
|
|
struct filestr_base *parentstrp = STREAM_FIRST(fobp);
|
|
struct fat_file *parentfilep = &parentstrp->infop->fatfile;
|
|
|
|
for (int i = 0; i < count; i++)
|
|
{
|
|
if (!fat_dir_is_parent(parentfilep, &infop[i]->fatfile))
|
|
continue;
|
|
|
|
/* discard scan/read caches' parent dir info */
|
|
FOR_EACH_STREAM(THIS, parentstrp, s)
|
|
filestr_discard_cache(s);
|
|
}
|
|
}
|
|
}
|
|
|
|
/* see if this file has open streams and return that fileobj_binding if so,
|
|
else grab a new one from the free list; returns true if this stream is
|
|
the only open one */
|
|
static bool binding_assign(const struct file_base_info *srcinfop,
|
|
struct fileobj_binding **fobpp)
|
|
{
|
|
FOR_EACH_BINDING(srcinfop->fatfile.volume, fobp)
|
|
{
|
|
if (fobp->flags & FO_REMOVED)
|
|
continue;
|
|
|
|
if (fat_file_is_same(&srcinfop->fatfile, &fobp->bind.info.fatfile))
|
|
{
|
|
/* already has open streams */
|
|
*fobpp = fobp;
|
|
return false;
|
|
}
|
|
}
|
|
|
|
/* not found - allocate anew */
|
|
*fobpp = BINDING_FIRST(FREE);
|
|
ll_remove_first(FREE_BINDINGS());
|
|
ll_init(&(*fobpp)->list);
|
|
return true;
|
|
}
|
|
|
|
/* mark descriptor as unused and return to the free list */
|
|
static void binding_add_to_free_list(struct fileobj_binding *fobp)
|
|
{
|
|
fobp->flags = 0;
|
|
ll_insert_last(FREE_BINDINGS(), &fobp->bind.node);
|
|
}
|
|
|
|
/** File and directory internal interface **/
|
|
|
|
void file_binding_insert_last(struct file_base_binding *bindp)
|
|
{
|
|
ll_insert_last(BASEBINDING_LIST(bindp), &bindp->node);
|
|
}
|
|
|
|
void file_binding_remove(struct file_base_binding *bindp)
|
|
{
|
|
ll_remove(BASEBINDING_LIST(bindp), &bindp->node);
|
|
}
|
|
|
|
#ifdef HAVE_DIRCACHE
|
|
void file_binding_insert_first(struct file_base_binding *bindp)
|
|
{
|
|
ll_insert_first(BASEBINDING_LIST(bindp), &bindp->node);
|
|
}
|
|
|
|
void file_binding_remove_next(struct file_base_binding *prevp,
|
|
struct file_base_binding *bindp)
|
|
{
|
|
ll_remove_next(BASEBINDING_LIST(bindp), &prevp->node);
|
|
(void)bindp;
|
|
}
|
|
#endif /* HAVE_DIRCACHE */
|
|
|
|
/* opens the file object for a new stream and sets up the caches;
|
|
* the stream must already be opened at the FS driver level and *stream
|
|
* initialized.
|
|
*
|
|
* NOTE: switches stream->infop to the one kept in common for all streams of
|
|
* the same file, making a copy for only the first stream
|
|
*/
|
|
void fileobj_fileop_open(struct filestr_base *stream,
|
|
const struct file_base_info *srcinfop,
|
|
unsigned int callflags)
|
|
{
|
|
struct fileobj_binding *fobp;
|
|
bool first = binding_assign(srcinfop, &fobp);
|
|
|
|
/* add stream to this file's list */
|
|
ll_insert_last(&fobp->list, &stream->node);
|
|
|
|
/* initiate the new stream into the enclave */
|
|
stream->flags = FDO_BUSY |
|
|
(callflags & (FF_MASK|FD_WRITE|FD_WRONLY|FD_APPEND));
|
|
stream->infop = &fobp->bind.info;
|
|
stream->fatstr.fatfilep = &fobp->bind.info.fatfile;
|
|
stream->bindp = &fobp->bind;
|
|
stream->mtx = &stream_mutexes[fobp - fobindings];
|
|
|
|
if (first)
|
|
{
|
|
/* first stream for file */
|
|
fobp->bind.info = *srcinfop;
|
|
fobp->flags = FDO_BUSY | FO_SINGLE |
|
|
(callflags & (FO_DIRECTORY|FO_TRUNC));
|
|
fobp->writers = 0;
|
|
fobp->size = 0;
|
|
|
|
fileobj_bind_file(&fobp->bind);
|
|
}
|
|
else
|
|
{
|
|
/* additional stream for file */
|
|
fobp->flags &= ~FO_SINGLE;
|
|
fobp->flags |= callflags & FO_TRUNC;
|
|
|
|
/* once a file/directory, always a file/directory; such a change
|
|
is a bug */
|
|
if ((callflags ^ fobp->flags) & FO_DIRECTORY)
|
|
{
|
|
DEBUGF("%s - FO_DIRECTORY flag does not match: %p %u\n",
|
|
__func__, stream, callflags);
|
|
}
|
|
}
|
|
|
|
if ((callflags & FD_WRITE) && ++fobp->writers == 1)
|
|
{
|
|
/* first writer */
|
|
file_cache_init(&fobp->cache);
|
|
FOR_EACH_STREAM(FIRST, fobp, s)
|
|
filestr_assign_cache(s, &fobp->cache);
|
|
}
|
|
else if (fobp->writers)
|
|
{
|
|
/* already writers present */
|
|
filestr_assign_cache(stream, &fobp->cache);
|
|
}
|
|
else
|
|
{
|
|
/* another reader and no writers present */
|
|
file_cache_reset(stream->cachep);
|
|
}
|
|
}
|
|
|
|
/* close the stream and free associated resources */
|
|
void fileobj_fileop_close(struct filestr_base *stream)
|
|
{
|
|
if (!(stream->flags & FDO_BUSY))
|
|
{
|
|
/* not added to manager or forced-closed by unmounting */
|
|
filestr_base_destroy(stream);
|
|
return;
|
|
}
|
|
|
|
struct fileobj_binding *fobp = (struct fileobj_binding *)stream->bindp;
|
|
unsigned int foflags = fobp->flags;
|
|
|
|
ll_remove(&fobp->list, &stream->node);
|
|
|
|
if (foflags & FO_SINGLE)
|
|
{
|
|
/* last stream for file; close everything */
|
|
fileobj_unbind_file(&fobp->bind);
|
|
|
|
if (fobp->writers)
|
|
file_cache_free(&fobp->cache);
|
|
|
|
binding_add_to_free_list(fobp);
|
|
}
|
|
else
|
|
{
|
|
if ((stream->flags & FD_WRITE) && --fobp->writers == 0)
|
|
{
|
|
/* only readers remain; switch back to stream-local caching */
|
|
FOR_EACH_STREAM(FIRST, fobp, s)
|
|
filestr_copy_cache(s, &fobp->cache);
|
|
|
|
file_cache_free(&fobp->cache);
|
|
}
|
|
|
|
if (fobp->list.head == fobp->list.tail)
|
|
fobp->flags |= FO_SINGLE; /* only one open stream remaining */
|
|
}
|
|
|
|
filestr_base_destroy(stream);
|
|
}
|
|
|
|
/* informs manager that file has been created */
|
|
void fileobj_fileop_create(struct filestr_base *stream,
|
|
const struct file_base_info *srcinfop,
|
|
unsigned int callflags)
|
|
{
|
|
fileobj_fileop_open(stream, srcinfop, callflags);
|
|
fileobj_sync_parent((const struct file_base_info *[]){ stream->infop }, 1);
|
|
}
|
|
|
|
/* informs manager that file has been removed */
|
|
void fileobj_fileop_remove(struct filestr_base *stream,
|
|
const struct file_base_info *oldinfop)
|
|
{
|
|
((struct fileobj_binding *)stream->bindp)->flags |= FO_REMOVED;
|
|
fileobj_sync_parent((const struct file_base_info *[]){ oldinfop }, 1);
|
|
}
|
|
|
|
/* informs manager that file has been renamed */
|
|
void fileobj_fileop_rename(struct filestr_base *stream,
|
|
const struct file_base_info *oldinfop)
|
|
{
|
|
/* if there is old info then this was a move and the old parent has to be
|
|
informed */
|
|
int count = oldinfop ? 2 : 1;
|
|
fileobj_sync_parent(&(const struct file_base_info *[])
|
|
{ oldinfop, stream->infop }[2 - count],
|
|
count);
|
|
}
|
|
|
|
/* informs manager than directory entries have been updated */
|
|
void fileobj_fileop_sync(struct filestr_base *stream)
|
|
{
|
|
if (((struct fileobj_binding *)stream->bindp)->flags & FO_REMOVED)
|
|
return; /* no dir to sync */
|
|
|
|
fileobj_sync_parent((const struct file_base_info *[]){ stream->infop }, 1);
|
|
}
|
|
|
|
/* query for the pointer to the size storage for the file object */
|
|
file_size_t * fileobj_get_sizep(const struct filestr_base *stream)
|
|
{
|
|
if (!stream->bindp)
|
|
return NULL;
|
|
|
|
return &((struct fileobj_binding *)stream->bindp)->size;
|
|
}
|
|
|
|
/* iterate the list of streams for this stream's file */
|
|
struct filestr_base * fileobj_get_next_stream(const struct filestr_base *stream,
|
|
const struct filestr_base *s)
|
|
{
|
|
if (!stream->bindp)
|
|
return NULL;
|
|
|
|
return s ? STREAM_NEXT(s) : STREAM_FIRST((struct fileobj_binding *)stream->bindp);
|
|
}
|
|
|
|
/* query manager bitflags for the file object */
|
|
unsigned int fileobj_get_flags(const struct filestr_base *stream)
|
|
{
|
|
if (!stream->bindp)
|
|
return 0;
|
|
|
|
return ((struct fileobj_binding *)stream->bindp)->flags;
|
|
}
|
|
|
|
/* change manager bitflags for the file object (permitted only) */
|
|
void fileobj_change_flags(struct filestr_base *stream,
|
|
unsigned int flags, unsigned int mask)
|
|
{
|
|
struct fileobj_binding *fobp = (struct fileobj_binding *)stream->bindp;
|
|
if (!fobp)
|
|
return;
|
|
|
|
mask &= FDO_CHG_MASK;
|
|
fobp->flags = (fobp->flags & ~mask) | (flags & mask);
|
|
}
|
|
|
|
/* mark all open streams on a device as "nonexistant" */
|
|
void fileobj_mgr_unmount(IF_MV_NONVOID(int volume))
|
|
{
|
|
FOR_EACH_VOLUME(volume, v)
|
|
{
|
|
struct fileobj_binding *fobp;
|
|
while ((fobp = BINDING_FIRST(BUSY, v)))
|
|
{
|
|
struct filestr_base *s;
|
|
while ((s = STREAM_FIRST(fobp)))
|
|
{
|
|
/* last ditch effort to preserve FS integrity; we could still
|
|
be alive (soft unmount, maybe); we get informed early */
|
|
fileop_onunmount_internal(s);
|
|
|
|
if (STREAM_FIRST(fobp) == s)
|
|
fileop_onclose_internal(s); /* above didn't close it */
|
|
|
|
/* keep it "busy" to avoid races; any valid file/directory
|
|
descriptor returned by an open call should always be
|
|
closed by whoever opened it (of course!) */
|
|
s->flags = (s->flags & ~FDO_BUSY) | FD_NONEXIST;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
/* one-time init at startup */
|
|
void fileobj_mgr_init(void)
|
|
{
|
|
for (unsigned int i = 0; i < NUM_VOLUMES; i++)
|
|
ll_init(BUSY_BINDINGS(i));
|
|
|
|
ll_init(FREE_BINDINGS());
|
|
for (unsigned int i = 0; i < MAX_FILEOBJS; i++)
|
|
{
|
|
mutex_init(&stream_mutexes[i]);
|
|
binding_add_to_free_list(&fobindings[i]);
|
|
}
|
|
}
|