factor the filedescriptorregistry out, closes #395
also introduces a new mutex for lookup/creating files to prevent races
This commit is contained in:
Christian Thaeter
parent
53a747dcca
commit
d45b2eef91
7 changed files with 257 additions and 130 deletions
|
|
@ -30,6 +30,7 @@ liblumierabackend_la_SOURCES = \
|
|||
$(liblumierabackend_la_srcdir)/file.c \
|
||||
$(liblumierabackend_la_srcdir)/filehandle.c \
|
||||
$(liblumierabackend_la_srcdir)/filedescriptor.c \
|
||||
$(liblumierabackend_la_srcdir)/filedescriptorregistry.c \
|
||||
$(liblumierabackend_la_srcdir)/filehandlecache.c \
|
||||
$(liblumierabackend_la_srcdir)/mmap.c \
|
||||
$(liblumierabackend_la_srcdir)/mmapings.c \
|
||||
|
|
@ -47,6 +48,7 @@ noinst_HEADERS += \
|
|||
$(liblumierabackend_la_srcdir)/file.h \
|
||||
$(liblumierabackend_la_srcdir)/filehandle.h \
|
||||
$(liblumierabackend_la_srcdir)/filedescriptor.h \
|
||||
$(liblumierabackend_la_srcdir)/filedescriptorregistry.h \
|
||||
$(liblumierabackend_la_srcdir)/filehandlecache.h \
|
||||
$(liblumierabackend_la_srcdir)/mmap.h \
|
||||
$(liblumierabackend_la_srcdir)/mmapings.h \
|
||||
|
|
|
|||
|
|
@ -26,6 +26,7 @@
|
|||
#include "common/config.h"
|
||||
#include "backend/filehandlecache.h"
|
||||
#include "backend/filedescriptor.h"
|
||||
#include "backend/filedescriptorregistry.h"
|
||||
#include "backend/mmapcache.h"
|
||||
#include "backend/threadpool.h"
|
||||
|
||||
|
|
@ -65,9 +66,11 @@ lumiera_backend_init (void)
|
|||
|
||||
TRACE (backend_dbg);
|
||||
|
||||
lumiera_mutex_init (&lumiera_filecreate_mutex, "fileaccess", &NOBUG_FLAG (mutex_dbg), NOBUG_CONTEXT);
|
||||
|
||||
lumiera_threadpool_init ();
|
||||
|
||||
lumiera_filedescriptor_registry_init ();
|
||||
lumiera_filedescriptorregistry_init ();
|
||||
|
||||
lumiera_backend_pagesize = sysconf(_SC_PAGESIZE);
|
||||
|
||||
|
|
@ -115,6 +118,9 @@ lumiera_backend_destroy (void)
|
|||
TRACE (backend_dbg);
|
||||
lumiera_mmapcache_delete ();
|
||||
lumiera_filehandlecache_delete ();
|
||||
lumiera_filedescriptor_registry_destroy ();
|
||||
lumiera_filedescriptorregistry_destroy ();
|
||||
lumiera_threadpool_destroy ();
|
||||
|
||||
lumiera_mutex_destroy (&lumiera_filecreate_mutex, &NOBUG_FLAG (mutex_dbg), NOBUG_CONTEXT);
|
||||
}
|
||||
|
||||
|
|
|
|||
|
|
@ -21,12 +21,21 @@
|
|||
#ifndef LUMIERA_BACKEND_H
|
||||
#define LUMIERA_BACKEND_H
|
||||
|
||||
#include "lib/mutex.h"
|
||||
|
||||
#include <nobug.h>
|
||||
|
||||
//NOBUG_DECLARE_FLAG (backend);
|
||||
|
||||
extern size_t lumiera_backend_pagesize;
|
||||
|
||||
/**
|
||||
* Protect lookup and creation of files.
|
||||
* Trying to access a nonexistent file with O_CREAT would be racy.
|
||||
* Defined in filedescriptor.c
|
||||
*/
|
||||
extern lumiera_mutex lumiera_filecreate_mutex;
|
||||
|
||||
|
||||
int
|
||||
lumiera_backend_init (void);
|
||||
|
|
|
|||
|
|
@ -25,6 +25,7 @@
|
|||
|
||||
#include "backend/file.h"
|
||||
#include "backend/filedescriptor.h"
|
||||
#include "backend/filedescriptorregistry.h"
|
||||
#include "backend/filehandle.h"
|
||||
#include "backend/filehandlecache.h"
|
||||
|
||||
|
|
@ -37,94 +38,19 @@
|
|||
|
||||
//NOBUG_DEFINE_FLAG_PARENT (filedescriptor, file_all);
|
||||
|
||||
/*
|
||||
Filedescriptor registry
|
||||
|
||||
This registry stores all acquired filedescriptors for lookup, they will be freed when not referenced anymore.
|
||||
*/
|
||||
static PSplay registry = NULL;
|
||||
static lumiera_mutex registry_mutex;
|
||||
|
||||
|
||||
static int
|
||||
cmp_fn (const void* keya, const void* keyb)
|
||||
{
|
||||
const LumieraFiledescriptor a = (const LumieraFiledescriptor)keya;
|
||||
const LumieraFiledescriptor b = (const LumieraFiledescriptor)keyb;
|
||||
|
||||
if (a->stat.st_dev < b->stat.st_dev)
|
||||
return -1;
|
||||
else if (a->stat.st_dev > b->stat.st_dev)
|
||||
return 1;
|
||||
|
||||
if (a->stat.st_ino < b->stat.st_ino)
|
||||
return -1;
|
||||
else if (a->stat.st_ino > b->stat.st_ino)
|
||||
return 1;
|
||||
|
||||
if ((a->flags&LUMIERA_FILE_MASK) < (b->flags&LUMIERA_FILE_MASK))
|
||||
return -1;
|
||||
else if ((a->flags&LUMIERA_FILE_MASK) > (b->flags&LUMIERA_FILE_MASK))
|
||||
return 1;
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
|
||||
static void
|
||||
delete_fn (PSplaynode node)
|
||||
{
|
||||
TODO ("figure name out? or is the handle here always closed");
|
||||
lumiera_filedescriptor_delete ((LumieraFiledescriptor) node, NULL);
|
||||
}
|
||||
|
||||
|
||||
static const void*
|
||||
key_fn (const PSplaynode node)
|
||||
{
|
||||
return node;
|
||||
}
|
||||
|
||||
|
||||
|
||||
void
|
||||
lumiera_filedescriptor_registry_init (void)
|
||||
{
|
||||
//NOBUG_INIT_FLAG (filedescriptor);
|
||||
TRACE (filedescriptor_dbg);
|
||||
REQUIRE (!registry);
|
||||
|
||||
registry = psplay_new (cmp_fn, key_fn, delete_fn);
|
||||
if (!registry)
|
||||
LUMIERA_DIE (NO_MEMORY);
|
||||
|
||||
lumiera_mutex_init (®istry_mutex, "filedescriptor_registry", &NOBUG_FLAG (mutex_dbg), NOBUG_CONTEXT);
|
||||
}
|
||||
|
||||
void
|
||||
lumiera_filedescriptor_registry_destroy (void)
|
||||
{
|
||||
TRACE (filedescriptor_dbg);
|
||||
REQUIRE (!psplay_nelements (registry));
|
||||
|
||||
lumiera_mutex_destroy (®istry_mutex, &NOBUG_FLAG (mutex_dbg), NOBUG_CONTEXT);
|
||||
|
||||
if (registry)
|
||||
psplay_destroy (registry);
|
||||
registry = NULL;
|
||||
}
|
||||
/* lookup and creation of files, initialized in backend.c */
|
||||
lumiera_mutex lumiera_filecreate_mutex;
|
||||
|
||||
|
||||
LumieraFiledescriptor
|
||||
lumiera_filedescriptor_acquire (const char* name, int flags, LList filenode)
|
||||
{
|
||||
TRACE (filedescriptor_dbg, "%s", name);
|
||||
REQUIRE (registry, "not initialized");
|
||||
REQUIRE (llist_is_empty (filenode));
|
||||
|
||||
LumieraFiledescriptor dest = NULL;
|
||||
|
||||
LUMIERA_MUTEX_SECTION (mutex_sync, ®istry_mutex)
|
||||
LUMIERA_MUTEX_SECTION (mutex_sync, &lumiera_filecreate_mutex)
|
||||
{
|
||||
lumiera_filedescriptor fdesc;
|
||||
fdesc.flags = flags;
|
||||
|
|
@ -167,25 +93,21 @@ lumiera_filedescriptor_acquire (const char* name, int flags, LList filenode)
|
|||
}
|
||||
|
||||
/* lookup/create descriptor */
|
||||
dest = (LumieraFiledescriptor) psplay_find (registry, &fdesc, 100);
|
||||
dest = lumiera_filedescriptorregistry_ensure (&fdesc);
|
||||
|
||||
if (!dest)
|
||||
{
|
||||
dest = lumiera_filedescriptor_new (&fdesc);
|
||||
if (!dest)
|
||||
goto error;
|
||||
if (dest)
|
||||
llist_insert_head (&dest->files, filenode);
|
||||
|
||||
psplay_insert (registry, &dest->node, 100);
|
||||
}
|
||||
|
||||
llist_insert_head (&dest->files, filenode);
|
||||
error: ;
|
||||
error:
|
||||
;
|
||||
}
|
||||
|
||||
return dest;
|
||||
}
|
||||
|
||||
|
||||
|
||||
|
||||
void
|
||||
lumiera_filedescriptor_release (LumieraFiledescriptor self, const char* name, LList filenode)
|
||||
{
|
||||
|
|
@ -288,29 +210,25 @@ lumiera_filedescriptor_delete (LumieraFiledescriptor self, const char* name)
|
|||
{
|
||||
TRACE (filedescriptor_dbg, "%p %s", self, name);
|
||||
|
||||
LUMIERA_MUTEX_SECTION (mutex_sync, ®istry_mutex)
|
||||
REQUIRE (llist_is_empty (&self->files));
|
||||
|
||||
lumiera_filedescriptorregistry_remove (self);
|
||||
|
||||
TODO ("destruct other members (WIP)");
|
||||
|
||||
lumiera_mmapings_delete (self->mmapings);
|
||||
|
||||
if (self->handle && name && ((self->flags & O_RDWR) == O_RDWR))
|
||||
{
|
||||
REQUIRE (llist_is_empty (&self->files));
|
||||
|
||||
psplay_remove (registry, &self->node);
|
||||
|
||||
TODO ("destruct other members (WIP)");
|
||||
|
||||
if (self->handle && name && ((self->flags & O_RDWR) == O_RDWR))
|
||||
{
|
||||
TRACE (filedescriptor_dbg, "truncate %s to %lld", name, (long long)self->realsize);
|
||||
lumiera_filehandlecache_checkout (self->handle);
|
||||
int dummy = ftruncate (lumiera_filehandle_handle (self->handle), self->realsize);
|
||||
(void) dummy; /* this is present to silence a warning */
|
||||
TODO ("handle error case better");
|
||||
lumiera_filehandlecache_checkin (self->handle);
|
||||
}
|
||||
|
||||
lumiera_mmapings_delete (self->mmapings);
|
||||
|
||||
TODO ("release filehandle");
|
||||
|
||||
lumiera_mutex_destroy (&self->lock, &NOBUG_FLAG (mutex_dbg), NOBUG_CONTEXT);
|
||||
lumiera_free (self);
|
||||
TRACE (filedescriptor_dbg, "truncate %s to %lld", name, (long long)self->realsize);
|
||||
lumiera_filehandlecache_checkout (self->handle);
|
||||
int dummy = ftruncate (lumiera_filehandle_handle (self->handle), self->realsize);
|
||||
(void) dummy; /* this is present to silence a warning */
|
||||
TODO ("handle error case better");
|
||||
lumiera_filehandlecache_checkin (self->handle);
|
||||
TODO ("really release filehandle");
|
||||
}
|
||||
|
||||
lumiera_mutex_destroy (&self->lock, &NOBUG_FLAG (mutex_dbg), NOBUG_CONTEXT);
|
||||
lumiera_free (self);
|
||||
}
|
||||
|
|
|
|||
|
|
@ -75,22 +75,6 @@ struct lumiera_filedescriptor_struct
|
|||
llist files;
|
||||
};
|
||||
|
||||
/**
|
||||
* Initialize the global filedescriptor registry.
|
||||
* All filedescriptors are looked up by dev/ino/open-flags in a hashtable. Opening hardlinked
|
||||
* files will be targeted to the same filedescriptor.
|
||||
* This function never fails but dies on error.
|
||||
*/
|
||||
void
|
||||
lumiera_filedescriptor_registry_init (void);
|
||||
|
||||
/**
|
||||
* Destroy and free the global filedescriptor registry.
|
||||
* Never fails.
|
||||
*/
|
||||
void
|
||||
lumiera_filedescriptor_registry_destroy (void);
|
||||
|
||||
|
||||
/**
|
||||
* Find existing filedescriptor or create one
|
||||
|
|
|
|||
150
src/backend/filedescriptorregistry.c
Normal file
150
src/backend/filedescriptorregistry.c
Normal file
|
|
@ -0,0 +1,150 @@
|
|||
/*
|
||||
filedescriptorregistry.c - register all files in use
|
||||
|
||||
Copyright (C) Lumiera.org
|
||||
2008, 2010, Christian Thaeter <ct@pipapo.org>
|
||||
|
||||
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 program is distributed in the hope that it will be useful,
|
||||
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||||
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
||||
GNU General Public License for more details.
|
||||
|
||||
You should have received a copy of the GNU General Public License
|
||||
along with this program; if not, write to the Free Software
|
||||
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
|
||||
*/
|
||||
|
||||
#include "include/logging.h"
|
||||
#include "lib/safeclib.h"
|
||||
#include "lib/mutex.h"
|
||||
#include "lib/psplay.h"
|
||||
|
||||
#include "backend/file.h"
|
||||
#include "backend/filedescriptor.h"
|
||||
#include "backend/filedescriptorregistry.h"
|
||||
|
||||
//NOBUG_DEFINE_FLAG_PARENT (filedescriptorregistry, file_all);
|
||||
|
||||
/*
|
||||
Filedescriptor registry
|
||||
|
||||
This registry stores all acquired filedescriptors for lookup, they will be freed when not referenced anymore.
|
||||
*/
|
||||
static PSplay filedescriptorregistry = NULL;
|
||||
static lumiera_mutex filedescriptorregistry_mutex;
|
||||
|
||||
|
||||
static int
|
||||
cmp_fn (const void* keya, const void* keyb)
|
||||
{
|
||||
const LumieraFiledescriptor a = (const LumieraFiledescriptor)keya;
|
||||
const LumieraFiledescriptor b = (const LumieraFiledescriptor)keyb;
|
||||
|
||||
if (a->stat.st_dev < b->stat.st_dev)
|
||||
return -1;
|
||||
else if (a->stat.st_dev > b->stat.st_dev)
|
||||
return 1;
|
||||
|
||||
if (a->stat.st_ino < b->stat.st_ino)
|
||||
return -1;
|
||||
else if (a->stat.st_ino > b->stat.st_ino)
|
||||
return 1;
|
||||
|
||||
if ((a->flags&LUMIERA_FILE_MASK) < (b->flags&LUMIERA_FILE_MASK))
|
||||
return -1;
|
||||
else if ((a->flags&LUMIERA_FILE_MASK) > (b->flags&LUMIERA_FILE_MASK))
|
||||
return 1;
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
|
||||
static void
|
||||
delete_fn (PSplaynode node)
|
||||
{
|
||||
TODO ("figure name out? or is the handle here always closed");
|
||||
lumiera_filedescriptor_delete ((LumieraFiledescriptor) node, NULL);
|
||||
}
|
||||
|
||||
|
||||
static const void*
|
||||
key_fn (const PSplaynode node)
|
||||
{
|
||||
return node;
|
||||
}
|
||||
|
||||
|
||||
|
||||
void
|
||||
lumiera_filedescriptorregistry_init (void)
|
||||
{
|
||||
TRACE (filedescriptor_dbg);
|
||||
REQUIRE (!filedescriptorregistry);
|
||||
|
||||
filedescriptorregistry = psplay_new (cmp_fn, key_fn, delete_fn);
|
||||
if (!filedescriptorregistry)
|
||||
LUMIERA_DIE (NO_MEMORY);
|
||||
|
||||
lumiera_mutex_init (&filedescriptorregistry_mutex, "filedescriptorregistry", &NOBUG_FLAG (mutex_dbg), NOBUG_CONTEXT);
|
||||
}
|
||||
|
||||
void
|
||||
lumiera_filedescriptorregistry_destroy (void)
|
||||
{
|
||||
TRACE (filedescriptor_dbg);
|
||||
REQUIRE (!psplay_nelements (filedescriptorregistry));
|
||||
|
||||
lumiera_mutex_destroy (&filedescriptorregistry_mutex, &NOBUG_FLAG (mutex_dbg), NOBUG_CONTEXT);
|
||||
|
||||
if (filedescriptorregistry)
|
||||
psplay_destroy (filedescriptorregistry);
|
||||
|
||||
filedescriptorregistry = NULL;
|
||||
}
|
||||
|
||||
|
||||
LumieraFiledescriptor
|
||||
lumiera_filedescriptorregistry_ensure (LumieraFiledescriptor template)
|
||||
{
|
||||
REQUIRE (filedescriptorregistry, "not initialized");
|
||||
|
||||
LumieraFiledescriptor ret = NULL;
|
||||
|
||||
LUMIERA_MUTEX_SECTION (mutex_sync, &filedescriptorregistry_mutex)
|
||||
{
|
||||
/* lookup/create descriptor */
|
||||
ret = (LumieraFiledescriptor) psplay_find (filedescriptorregistry, template, 100);
|
||||
|
||||
if (!ret)
|
||||
{
|
||||
ret = lumiera_filedescriptor_new (template);
|
||||
if (!ret)
|
||||
goto error;
|
||||
|
||||
psplay_insert (filedescriptorregistry, &ret->node, 100);
|
||||
}
|
||||
|
||||
error:
|
||||
;
|
||||
}
|
||||
|
||||
return ret;
|
||||
}
|
||||
|
||||
|
||||
/**
|
||||
* Removes a Filedescriptor from the registry.
|
||||
*/
|
||||
void
|
||||
lumiera_filedescriptorregistry_remove (LumieraFiledescriptor self)
|
||||
{
|
||||
LUMIERA_MUTEX_SECTION (mutex_sync, &filedescriptorregistry_mutex)
|
||||
psplay_remove (filedescriptorregistry, &self->node);
|
||||
}
|
||||
|
||||
|
||||
58
src/backend/filedescriptorregistry.h
Normal file
58
src/backend/filedescriptorregistry.h
Normal file
|
|
@ -0,0 +1,58 @@
|
|||
/*
|
||||
filedescriptorregistry.h - register all files in use
|
||||
|
||||
Copyright (C) Lumiera.org
|
||||
2008, 2010, Christian Thaeter <ct@pipapo.org>
|
||||
|
||||
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 program is distributed in the hope that it will be useful,
|
||||
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||||
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
||||
GNU General Public License for more details.
|
||||
|
||||
You should have received a copy of the GNU General Public License
|
||||
along with this program; if not, write to the Free Software
|
||||
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
|
||||
*/
|
||||
|
||||
#ifndef LUMIERA_FILEDESCRIPTORREGISTRY_H
|
||||
#define LUMIERA_FILEDESCRIPTORREGISTRY_H
|
||||
|
||||
#include "backend/filedescriptor.h"
|
||||
|
||||
|
||||
/**
|
||||
* Initialize the global filedescriptor registry.
|
||||
* Opening hardlinked files will be targeted to the same filedescriptor.
|
||||
* This function never fails but dies on error. TODO backend/subsystem failure
|
||||
*/
|
||||
void
|
||||
lumiera_filedescriptorregistry_init (void);
|
||||
|
||||
/**
|
||||
* Destroy and free the global filedescriptor registry.
|
||||
* Never fails.
|
||||
*/
|
||||
void
|
||||
lumiera_filedescriptorregistry_destroy (void);
|
||||
|
||||
/**
|
||||
* Ensures that a filedescriptor is in the registry.
|
||||
* Looks template up and if not found, create a new one from template.
|
||||
* @return filedescriptor from registry
|
||||
*/
|
||||
LumieraFiledescriptor
|
||||
lumiera_filedescriptorregistry_ensure (LumieraFiledescriptor template);
|
||||
|
||||
/**
|
||||
* Removes a Filedescriptor from the registry.
|
||||
*/
|
||||
void
|
||||
lumiera_filedescriptorregistry_remove (LumieraFiledescriptor self);
|
||||
|
||||
|
||||
#endif
|
||||
Loading…
Reference in a new issue