* need do nothing.
* RevokeValid set, Revoked set:
* buffer has been revoked.
+ *
+ * Locking rules:
+ * We keep two hash tables of revoke records. One hashtable belongs to the
+ * running transaction (is pointed to by journal->j_revoke), the other one
+ * belongs to the committing transaction. Accesses to the second hash table
+ * happen only from the kjournald and no other thread touches this table. Also
+ * journal_switch_revoke_table() which switches which hashtable belongs to the
+ * running and which to the committing transaction is called only from
+ * kjournald. Therefore we need no locks when accessing the hashtable belonging
+ * to the committing transaction.
+ *
+ * All users operating on the hash table belonging to the running transaction
+ * have a handle to the transaction. Therefore they are safe from kjournald
+ * switching hash tables under them. For operations on the lists of entries in
+ * the hash table j_revoke_lock is used.
+ *
+ * Finally, also replay code uses the hash tables but at this moment noone else
+ * can touch them (filesystem isn't mounted yet) and hence no locking is
+ * needed.
*/
#ifndef __KERNEL__
#include <linux/slab.h>
#include <linux/list.h>
#include <linux/init.h>
+#include <linux/bio.h>
#endif
#include <linux/log2.h>
{
struct list_head hash;
tid_t sequence; /* Used for recovery only */
- unsigned long blocknr;
+ unsigned int blocknr;
};
#ifdef __KERNEL__
static void write_one_revoke_record(journal_t *, transaction_t *,
struct journal_head **, int *,
- struct jbd_revoke_record_s *);
-static void flush_descriptor(journal_t *, struct journal_head *, int);
+ struct jbd_revoke_record_s *, int);
+static void flush_descriptor(journal_t *, struct journal_head *, int, int);
#endif
/* Utility functions to maintain the revoke table */
/* Borrowed from buffer.c: this is a tried and tested block hash function */
-static inline int hash(journal_t *journal, unsigned long block)
+static inline int hash(journal_t *journal, unsigned int block)
{
struct jbd_revoke_table_s *table = journal->j_revoke;
int hash_shift = table->hash_shift;
(block << (hash_shift - 12))) & (table->hash_size - 1);
}
-static int insert_revoke_hash(journal_t *journal, unsigned long blocknr,
+static int insert_revoke_hash(journal_t *journal, unsigned int blocknr,
tid_t seq)
{
struct list_head *hash_list;
/* Find a revoke record in the journal's hash table. */
static struct jbd_revoke_record_s *find_revoke_record(journal_t *journal,
- unsigned long blocknr)
+ unsigned int blocknr)
{
struct list_head *hash_list;
struct jbd_revoke_record_s *record;
* by one.
*/
-int journal_revoke(handle_t *handle, unsigned long blocknr,
+int journal_revoke(handle_t *handle, unsigned int blocknr,
struct buffer_head *bh_in)
{
struct buffer_head *bh = NULL;
}
}
- jbd_debug(2, "insert revoke for block %lu, bh_in=%p\n", blocknr, bh_in);
+ jbd_debug(2, "insert revoke for block %u, bh_in=%p\n", blocknr, bh_in);
err = insert_revoke_hash(journal, blocknr,
handle->h_transaction->t_tid);
BUFFER_TRACE(bh_in, "exit");
* the second time we would still have a pending revoke to cancel. So,
* do not trust the Revoked bit on buffers unless RevokeValid is also
* set.
- *
- * The caller must have the journal locked.
*/
int journal_cancel_revoke(handle_t *handle, struct journal_head *jh)
{
/*
* Write revoke records to the journal for all entries in the current
* revoke hash, deleting the entries as we go.
- *
- * Called with the journal lock held.
*/
-
void journal_write_revoke_records(journal_t *journal,
- transaction_t *transaction)
+ transaction_t *transaction, int write_op)
{
struct journal_head *descriptor;
struct jbd_revoke_record_s *record;
hash_list->next;
write_one_revoke_record(journal, transaction,
&descriptor, &offset,
- record);
+ record, write_op);
count++;
list_del(&record->hash);
kmem_cache_free(revoke_record_cache, record);
}
}
if (descriptor)
- flush_descriptor(journal, descriptor, offset);
+ flush_descriptor(journal, descriptor, offset, write_op);
jbd_debug(1, "Wrote %d revoke records\n", count);
}
transaction_t *transaction,
struct journal_head **descriptorp,
int *offsetp,
- struct jbd_revoke_record_s *record)
+ struct jbd_revoke_record_s *record,
+ int write_op)
{
struct journal_head *descriptor;
int offset;
/* Make sure we have a descriptor with space left for the record */
if (descriptor) {
if (offset == journal->j_blocksize) {
- flush_descriptor(journal, descriptor, offset);
+ flush_descriptor(journal, descriptor, offset, write_op);
descriptor = NULL;
}
}
static void flush_descriptor(journal_t *journal,
struct journal_head *descriptor,
- int offset)
+ int offset, int write_op)
{
journal_revoke_header_t *header;
struct buffer_head *bh = jh2bh(descriptor);
set_buffer_jwrite(bh);
BUFFER_TRACE(bh, "write");
set_buffer_dirty(bh);
- ll_rw_block(SWRITE, 1, &bh);
+ ll_rw_block((write_op == WRITE) ? SWRITE : SWRITE_SYNC_PLUG, 1, &bh);
}
#endif
*/
int journal_set_revoke(journal_t *journal,
- unsigned long blocknr,
+ unsigned int blocknr,
tid_t sequence)
{
struct jbd_revoke_record_s *record;
*/
int journal_test_revoke(journal_t *journal,
- unsigned long blocknr,
+ unsigned int blocknr,
tid_t sequence)
{
struct jbd_revoke_record_s *record;
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff