struct chlg_reader_state {
/* Shortcut to the corresponding OBD device */
- struct obd_device *crs_obd;
+ struct obd_device *crs_obd;
+ /* the corresponding chlg_registered_dev */
+ struct chlg_registered_dev *crs_ced;
/* Producer thread (if any) */
- struct task_struct *crs_prod_task;
+ struct task_struct *crs_prod_task;
/* An error occurred that prevents from reading further */
- int crs_err;
+ int crs_err;
/* EOF, no more records available */
- bool crs_eof;
+ bool crs_eof;
/* Desired start position */
- __u64 crs_start_offset;
+ __u64 crs_start_offset;
/* Wait queue for the catalog processing thread */
- wait_queue_head_t crs_waitq_prod;
+ wait_queue_head_t crs_waitq_prod;
/* Wait queue for the record copy threads */
- wait_queue_head_t crs_waitq_cons;
+ wait_queue_head_t crs_waitq_cons;
/* Mutex protecting crs_rec_count and crs_rec_queue */
- struct mutex crs_lock;
+ struct mutex crs_lock;
/* Number of item in the list */
- __u64 crs_rec_count;
+ __u64 crs_rec_count;
/* List of prefetched enqueued_record::enq_linkage_items */
- struct list_head crs_rec_queue;
- unsigned int crs_last_catidx;
- unsigned int crs_last_idx;
- bool crs_poll;
+ struct list_head crs_rec_queue;
+ unsigned int crs_last_catidx;
+ unsigned int crs_last_idx;
+ bool crs_poll;
};
struct chlg_rec_entry {
};
/**
+ * Deregister a changelog character device whose refcount has reached zero.
+ */
+static void chlg_dev_clear(struct kref *kref)
+{
+ struct chlg_registered_dev *entry = container_of(kref,
+ struct chlg_registered_dev,
+ ced_refs);
+ ENTRY;
+
+ list_del(&entry->ced_link);
+ misc_deregister(&entry->ced_misc);
+ OBD_FREE_PTR(entry);
+ EXIT;
+}
+
+static inline struct obd_device* chlg_obd_get(struct chlg_registered_dev *dev)
+{
+ struct obd_device *obd;
+
+ mutex_lock(&chlg_registered_dev_lock);
+ if (list_empty(&dev->ced_obds))
+ return NULL;
+
+ obd = list_first_entry(&dev->ced_obds, struct obd_device,
+ u.cli.cl_chg_dev_linkage);
+ class_incref(obd, "changelog", dev);
+ mutex_unlock(&chlg_registered_dev_lock);
+ return obd;
+}
+
+static inline void chlg_obd_put(struct chlg_registered_dev *dev,
+ struct obd_device *obd)
+{
+ class_decref(obd, "changelog", dev);
+}
+
+/**
* ChangeLog catalog processing callback invoked on each record.
* If the current record is eligible to userland delivery, push
* it into the crs_rec_queue where the consumer code will fetch it.
static int chlg_load(void *args)
{
struct chlg_reader_state *crs = args;
- struct obd_device *obd = crs->crs_obd;
+ struct chlg_registered_dev *ced = crs->crs_ced;
+ struct obd_device *obd = NULL;
struct llog_ctxt *ctx = NULL;
struct llog_handle *llh = NULL;
int rc;
ENTRY;
- ctx = llog_get_context(obd, LLOG_CHANGELOG_REPL_CTXT);
- if (ctx == NULL)
- GOTO(err_out, rc = -ENOENT);
-
crs->crs_last_catidx = -1;
crs->crs_last_idx = 0;
again:
+ obd = chlg_obd_get(ced);
+ if (obd == NULL)
+ RETURN(-ENODEV);
+
+ crs->crs_obd = obd;
+
+ ctx = llog_get_context(obd, LLOG_CHANGELOG_REPL_CTXT);
+ if (ctx == NULL)
+ GOTO(err_out, rc = -ENOENT);
+
rc = llog_open(NULL, ctx, &llh, NULL, CHANGELOG_CATALOG,
LLOG_OPEN_EXISTS);
if (rc) {
}
if (!kthread_should_stop() && crs->crs_poll) {
llog_cat_close(NULL, llh);
- schedule_timeout_interruptible(HZ);
+ llog_ctxt_put(ctx);
+ class_decref(obd, "changelog", crs);
+ schedule_timeout_interruptible(cfs_time_seconds(1));
goto again;
}
if (ctx != NULL)
llog_ctxt_put(ctx);
+ crs->crs_obd = NULL;
+ chlg_obd_put(ced, obd);
wait_event_interruptible(crs->crs_waitq_prod, kthread_should_stop());
RETURN(rc);
*/
static int chlg_clear(struct chlg_reader_state *crs, __u32 reader, __u64 record)
{
- struct obd_device *obd = crs->crs_obd;
+ struct obd_device *obd = NULL;
struct changelog_setinfo cs = {
.cs_recno = record,
.cs_id = reader
};
+ int rc;
+
+ obd = chlg_obd_get(crs->crs_ced);
+ if (obd == NULL)
+ return -ENODEV;
- return obd_set_info_async(NULL, obd->obd_self_export,
- strlen(KEY_CHANGELOG_CLEAR),
- KEY_CHANGELOG_CLEAR, sizeof(cs), &cs, NULL);
+ rc = obd_set_info_async(NULL, obd->obd_self_export,
+ strlen(KEY_CHANGELOG_CLEAR),
+ KEY_CHANGELOG_CLEAR, sizeof(cs), &cs, NULL);
+
+ chlg_obd_put(crs->crs_ced, obd);
+ return rc;
}
/** Maximum changelog control command size */
}
/**
- * Find the OBD device associated to a changelog character device.
- * @param[in] cdev character device instance descriptor
- * @return corresponding OBD device or NULL if none was found.
- */
-static struct obd_device *chlg_obd_get(dev_t cdev)
-{
- int minor = MINOR(cdev);
- struct obd_device *obd = NULL;
- struct chlg_registered_dev *curr;
-
- mutex_lock(&chlg_registered_dev_lock);
- list_for_each_entry(curr, &chlg_registered_devices, ced_link) {
- if (curr->ced_misc.minor == minor) {
- /* take the first available OBD device attached */
- obd = list_first_entry(&curr->ced_obds,
- struct obd_device,
- u.cli.cl_chg_dev_linkage);
- break;
- }
- }
- mutex_unlock(&chlg_registered_dev_lock);
- return obd;
-}
-
-/**
* Open handler, initialize internal CRS state and spawn prefetch thread if
* needed.
* @param[in] inode Inode struct for the open character device.
static int chlg_open(struct inode *inode, struct file *file)
{
struct chlg_reader_state *crs;
- struct obd_device *obd = chlg_obd_get(inode->i_rdev);
+ struct miscdevice *misc = file->private_data;
+ struct chlg_registered_dev *dev;
struct task_struct *task;
int rc;
ENTRY;
- if (!obd)
- RETURN(-ENODEV);
+ dev = container_of(misc, struct chlg_registered_dev, ced_misc);
OBD_ALLOC_PTR(crs);
if (!crs)
RETURN(-ENOMEM);
- crs->crs_obd = obd;
+ kref_get(&dev->ced_refs);
+ crs->crs_ced = dev;
crs->crs_err = false;
crs->crs_eof = false;
if (IS_ERR(task)) {
rc = PTR_ERR(task);
CERROR("%s: cannot start changelog thread: rc = %d\n",
- obd->obd_name, rc);
+ dev->ced_name, rc);
GOTO(err_crs, rc);
}
crs->crs_prod_task = task;
RETURN(0);
err_crs:
+ kref_put(&dev->ced_refs, chlg_dev_clear);
OBD_FREE_PTR(crs);
return rc;
}
list_for_each_entry_safe(rec, tmp, &crs->crs_rec_queue, enq_linkage)
enq_record_delete(rec);
+ kref_put(&crs->crs_ced->ced_refs, chlg_dev_clear);
OBD_FREE_PTR(crs);
return rc;
{
struct chlg_registered_dev *dit;
+ LASSERT(mutex_is_locked(&chlg_registered_dev_lock));
list_for_each_entry(dit, &chlg_registered_devices, ced_link)
if (strcmp(name, dit->ced_name) == 0)
return dit;
struct chlg_registered_dev *dit;
struct obd_device *oit;
+ LASSERT(mutex_is_locked(&chlg_registered_dev_lock));
list_for_each_entry(dit, &chlg_registered_devices, ced_link)
list_for_each_entry(oit, &dit->ced_obds,
u.cli.cl_chg_dev_linkage)
GOTO(out_unlock, rc = 0);
}
+ list_add_tail(&obd->u.cli.cl_chg_dev_linkage, &entry->ced_obds);
+ list_add_tail(&entry->ced_link, &chlg_registered_devices);
+
/* Register new character device */
rc = misc_register(&entry->ced_misc);
- if (rc != 0)
+ if (rc != 0) {
+ list_del_init(&obd->u.cli.cl_chg_dev_linkage);
+ list_del(&entry->ced_link);
GOTO(out_unlock, rc);
-
- list_add_tail(&obd->u.cli.cl_chg_dev_linkage, &entry->ced_obds);
- list_add_tail(&entry->ced_link, &chlg_registered_devices);
+ }
entry = NULL; /* prevent it from being freed below */
}
/**
- * Deregister a changelog character device whose refcount has reached zero.
- */
-static void chlg_dev_clear(struct kref *kref)
-{
- struct chlg_registered_dev *entry = container_of(kref,
- struct chlg_registered_dev,
- ced_refs);
- ENTRY;
-
- list_del(&entry->ced_link);
- misc_deregister(&entry->ced_misc);
- OBD_FREE_PTR(entry);
- EXIT;
-}
-
-/**
* Release OBD, decrease reference count of the corresponding changelog device.
*/
void mdc_changelog_cdev_finish(struct obd_device *obd)
{
- struct chlg_registered_dev *dev = chlg_registered_dev_find_by_obd(obd);
- ENTRY;
+ struct chlg_registered_dev *dev;
+ ENTRY;
mutex_lock(&chlg_registered_dev_lock);
+ dev = chlg_registered_dev_find_by_obd(obd);
list_del_init(&obd->u.cli.cl_chg_dev_linkage);
kref_put(&dev->ced_refs, chlg_dev_clear);
mutex_unlock(&chlg_registered_dev_lock);
git://git.whamcloud.com / fs / lustre-release.git / blobdiff