diff options
author | Paolo Bonzini <pbonzini@redhat.com> | 2012-09-18 13:26:25 +0200 |
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committer | Paolo Bonzini <pbonzini@redhat.com> | 2012-09-19 15:26:28 +0200 |
commit | 2c8d9f065538a5a0ef2421e90b6076d05148accf (patch) | |
tree | e302eabc6302f61e5a2f1c41f7afe7b06f7cbdab /nbd.c | |
parent | ff2b68aa70d10b7eae813b04e9a23723dbd89ebd (diff) | |
download | qemu-2c8d9f065538a5a0ef2421e90b6076d05148accf.zip qemu-2c8d9f065538a5a0ef2421e90b6076d05148accf.tar.gz qemu-2c8d9f065538a5a0ef2421e90b6076d05148accf.tar.bz2 |
nbd: add reference counting to NBDExport
We will use a similar two-phase destruction for NBDExport, so we need
each NBDClient to add a reference to NBDExport.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'nbd.c')
-rw-r--r-- | nbd.c | 37 |
1 files changed, 31 insertions, 6 deletions
@@ -89,6 +89,7 @@ struct NBDRequest { }; struct NBDExport { + int refcount; BlockDriverState *bs; off_t dev_offset; off_t size; @@ -664,6 +665,7 @@ void nbd_client_put(NBDClient *client) qemu_set_fd_handler2(client->sock, NULL, NULL, NULL, NULL); close(client->sock); client->sock = -1; + nbd_export_put(client->exp); g_free(client); } } @@ -722,6 +724,7 @@ NBDExport *nbd_export_new(BlockDriverState *bs, off_t dev_offset, { NBDExport *exp = g_malloc0(sizeof(NBDExport)); QSIMPLEQ_INIT(&exp->requests); + exp->refcount = 1; exp->bs = bs; exp->dev_offset = dev_offset; exp->nbdflags = nbdflags; @@ -731,14 +734,34 @@ NBDExport *nbd_export_new(BlockDriverState *bs, off_t dev_offset, void nbd_export_close(NBDExport *exp) { - while (!QSIMPLEQ_EMPTY(&exp->requests)) { - NBDRequest *first = QSIMPLEQ_FIRST(&exp->requests); - QSIMPLEQ_REMOVE_HEAD(&exp->requests, entry); - qemu_vfree(first->data); - g_free(first); + assert(exp->refcount == 1); + + /* stub */ +} + +void nbd_export_get(NBDExport *exp) +{ + assert(exp->refcount > 0); + exp->refcount++; +} + +void nbd_export_put(NBDExport *exp) +{ + assert(exp->refcount > 0); + if (exp->refcount == 1) { + nbd_export_close(exp); } - g_free(exp); + if (--exp->refcount == 0) { + while (!QSIMPLEQ_EMPTY(&exp->requests)) { + NBDRequest *first = QSIMPLEQ_FIRST(&exp->requests); + QSIMPLEQ_REMOVE_HEAD(&exp->requests, entry); + qemu_vfree(first->data); + g_free(first); + } + + g_free(exp); + } } static int nbd_can_read(void *opaque); @@ -1011,5 +1034,7 @@ NBDClient *nbd_client_new(NBDExport *exp, int csock, client->close = close; qemu_co_mutex_init(&client->send_lock); qemu_set_fd_handler2(csock, nbd_can_read, nbd_read, NULL, client); + + nbd_export_get(exp); return client; } |