/trunk/uspace/lib/libc/include/rwlock.h |
---|
44,6 → 44,9 |
typedef atomic_t rwlock_t; |
#define RWLOCK_INITIALIZE(rwlock) \ |
rwlock_t rwlock = FUTEX_INITIALIZER |
#define rwlock_initialize(rwlock) futex_initialize((rwlock), 1) |
#define rwlock_reader_lock(rwlock) futex_down((rwlock)) |
#define rwlock_writer_lock(rwlock) futex_down((rwlock)) |
/trunk/uspace/srv/vfs/vfs_unlink.c |
---|
35,14 → 35,13 |
* @brief |
*/ |
#include <atomic.h> |
#include <futex.h> |
#include <rwlock.h> |
/** |
* This futex prevents the race between a triplet-to-VFS-node resolution and a |
* This rwlock prevents the race between a triplet-to-VFS-node resolution and a |
* concurrent VFS operation which modifies the file system namespace. |
*/ |
atomic_t namespace_futex = FUTEX_INITIALIZER; |
RWLOCK_INITIALIZE(namespace_rwlock); |
/** |
* @} |
/trunk/uspace/srv/vfs/vfs_open.c |
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38,7 → 38,7 |
#include <ipc/ipc.h> |
#include <async.h> |
#include <errno.h> |
#include <futex.h> |
#include <rwlock.h> |
#include <sys/types.h> |
#include <stdlib.h> |
#include "vfs.h" |
93,7 → 93,7 |
* find/create-and-lock the VFS node corresponding to the looked-up |
* triplet. |
*/ |
futex_down(&namespace_futex); |
rwlock_reader_lock(&namespace_rwlock); |
/* |
* The path is now populated and we can call vfs_lookup_internal(). |
101,7 → 101,7 |
vfs_triplet_t triplet; |
rc = vfs_lookup_internal(path, size, &triplet, NULL); |
if (rc) { |
futex_up(&namespace_futex); |
rwlock_reader_unlock(&namespace_rwlock); |
ipc_answer_0(rid, rc); |
free(path); |
return; |
113,7 → 113,7 |
free(path); |
vfs_node_t *node = vfs_node_get(&triplet); |
futex_up(&namespace_futex); |
rwlock_reader_unlock(&namespace_rwlock); |
/* |
* Get ourselves a file descriptor and the corresponding vfs_file_t |
/trunk/uspace/srv/vfs/vfs_mount.c |
---|
182,13 → 182,13 |
/* |
* We already have the root FS. |
*/ |
futex_down(&namespace_futex); |
rwlock_writer_lock(&namespace_rwlock); |
rc = vfs_lookup_internal(buf, size, &mp, NULL); |
if (rc != EOK) { |
/* |
* The lookup failed for some reason. |
*/ |
futex_up(&namespace_futex); |
rwlock_writer_unlock(&namespace_rwlock); |
futex_up(&rootfs_futex); |
vfs_node_put(mr_node); /* failed -> drop reference */ |
free(buf); |
197,7 → 197,7 |
} |
mp_node = vfs_node_get(&mp); |
if (!mp_node) { |
futex_up(&namespace_futex); |
rwlock_writer_unlock(&namespace_rwlock); |
futex_up(&rootfs_futex); |
vfs_node_put(mr_node); /* failed -> drop reference */ |
free(buf); |
209,7 → 209,7 |
* It will be dropped upon the corresponding VFS_UNMOUNT. |
* This prevents the mount point from being deleted. |
*/ |
futex_up(&namespace_futex); |
rwlock_writer_unlock(&namespace_rwlock); |
} else { |
/* |
* We still don't have the root file system mounted. |
/trunk/uspace/srv/vfs/vfs.h |
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173,8 → 173,8 |
extern uint8_t *plb; /**< Path Lookup Buffer */ |
extern link_t plb_head; /**< List of active PLB entries. */ |
/** Holding this futex prevents extern changes in file system namespace. */ |
atomic_t namespace_futex; |
/** Holding this rwlock prevents changes in file system namespace. */ |
extern rwlock_t namespace_rwlock; |
extern int vfs_grab_phone(int); |
extern void vfs_release_phone(int); |