]> git.samba.org - metze/samba/wip.git/blobdiff - source3/smbd/oplock_linux.c
s3:smbd: make kernel oplocks event driven
[metze/samba/wip.git] / source3 / smbd / oplock_linux.c
index fa7cb42bc6d9ca4bcb17e617ad0a35ef01fa755e..51cce0ed48aa60600eaeed7751368519e4ba88b7 100644 (file)
 
 #define DBGC_CLASS DBGC_LOCKING
 #include "includes.h"
+#include "smbd/globals.h"
 
 #if HAVE_KERNEL_OPLOCKS_LINUX
 
-/* these can be removed when they are in glibc headers */
-struct  cap_user_header {
-       uint32 version;
-       int pid;
-} header;
-struct cap_user_data {
-       uint32 effective;
-       uint32 permitted;
-       uint32 inheritable;
-} data;
-
-extern int capget(struct cap_user_header * hdrp,
-                 struct cap_user_data * datap);
-extern int capset(struct cap_user_header * hdrp,
-                 const struct cap_user_data * datap);
-
-static SIG_ATOMIC_T signals_received;
-#define FD_PENDING_SIZE 100
-static SIG_ATOMIC_T fd_pending_array[FD_PENDING_SIZE];
-
 #ifndef F_SETLEASE
 #define F_SETLEASE     1024
 #endif
@@ -62,53 +43,12 @@ static SIG_ATOMIC_T fd_pending_array[FD_PENDING_SIZE];
 #define F_SETSIG 10
 #endif
 
-/****************************************************************************
- Handle a LEASE signal, incrementing the signals_received and blocking the signal.
-****************************************************************************/
-
-static void signal_handler(int sig, siginfo_t *info, void *unused)
-{
-       if (signals_received < FD_PENDING_SIZE - 1) {
-               fd_pending_array[signals_received] = (SIG_ATOMIC_T)info->si_fd;
-               signals_received++;
-       } /* Else signal is lost. */
-       sys_select_signal(RT_SIGNAL_LEASE);
-}
-
-/****************************************************************************
- Try to gain a linux capability.
-****************************************************************************/
-
-static void set_capability(unsigned capability)
-{
-#ifndef _LINUX_CAPABILITY_VERSION
-#define _LINUX_CAPABILITY_VERSION 0x19980330
-#endif
-       header.version = _LINUX_CAPABILITY_VERSION;
-       header.pid = 0;
-
-       if (capget(&header, &data) == -1) {
-               DEBUG(3,("Unable to get kernel capabilities (%s)\n",
-                        strerror(errno)));
-               return;
-       }
-
-       if (0 == (data.effective & (1<<capability))) {
-               data.effective |= (1<<capability);
-
-               if (capset(&header, &data) == -1) {
-                       DEBUG(3,("Unable to set %d capability (%s)\n", 
-                                capability, strerror(errno)));
-               }
-       }
-}
-
 /*
  * public function to get linux lease capability. Needed by some VFS modules (eg. gpfs.c)
  */
 void linux_set_lease_capability(void)
 {
-       set_capability(CAP_LEASE);
+       set_effective_capability(LEASE_CAPABILITY);
 }
 
 /* 
@@ -136,7 +76,7 @@ int linux_setlease(int fd, int leasetype)
 
        ret = fcntl(fd, F_SETLEASE, leasetype);
        if (ret == -1 && errno == EACCES) {
-               set_capability(CAP_LEASE);
+               set_effective_capability(LEASE_CAPABILITY);
                ret = fcntl(fd, F_SETLEASE, leasetype);
        }
 
@@ -148,31 +88,25 @@ int linux_setlease(int fd, int leasetype)
  * oplock break protocol.
 ****************************************************************************/
 
-static files_struct *linux_oplock_receive_message(fd_set *fds)
+static void linux_oplock_signal_handler(struct tevent_context *ev_ctx,
+                                       struct tevent_signal *se,
+                                       int signum, int count,
+                                       void *_info, void *private_data)
 {
-       int fd;
+       siginfo_t *info = (siginfo_t *)_info;
+       int fd = info->si_fd;
        files_struct *fsp;
 
-       BlockSignals(True, RT_SIGNAL_LEASE);
-       fd = fd_pending_array[0];
        fsp = file_find_fd(fd);
-       fd_pending_array[0] = (SIG_ATOMIC_T)-1;
-       if (signals_received > 1)
-                memmove(CONST_DISCARD(void *, &fd_pending_array[0]),
-                        CONST_DISCARD(void *, &fd_pending_array[1]),
-                       sizeof(SIG_ATOMIC_T)*(signals_received-1));
-       signals_received--;
-       /* now we can receive more signals */
-       BlockSignals(False, RT_SIGNAL_LEASE);
-
-       return fsp;
+       break_kernel_oplock(smbd_messaging_context(), fsp);
 }
 
 /****************************************************************************
  Attempt to set an kernel oplock on a file.
 ****************************************************************************/
 
-static bool linux_set_kernel_oplock(files_struct *fsp, int oplock_type)
+static bool linux_set_kernel_oplock(struct kernel_oplocks *ctx,
+                                   files_struct *fsp, int oplock_type)
 {
        if ( SMB_VFS_LINUX_SETLEASE(fsp, F_WRLCK) == -1) {
                DEBUG(3,("linux_set_kernel_oplock: Refused oplock on file %s, "
@@ -195,7 +129,8 @@ static bool linux_set_kernel_oplock(files_struct *fsp, int oplock_type)
  Release a kernel oplock on a file.
 ****************************************************************************/
 
-static void linux_release_kernel_oplock(files_struct *fsp)
+static void linux_release_kernel_oplock(struct kernel_oplocks *ctx,
+                                       files_struct *fsp)
 {
        if (DEBUGLVL(10)) {
                /*
@@ -224,15 +159,6 @@ static void linux_release_kernel_oplock(files_struct *fsp)
        }
 }
 
-/****************************************************************************
- See if a oplock message is waiting.
-****************************************************************************/
-
-static bool linux_oplock_msg_waiting(fd_set *fds)
-{
-       return signals_received != 0;
-}
-
 /****************************************************************************
  See if the kernel supports oplocks.
 ****************************************************************************/
@@ -252,39 +178,45 @@ static bool linux_oplocks_available(void)
  Setup kernel oplocks.
 ****************************************************************************/
 
-struct kernel_oplocks *linux_init_kernel_oplocks(void) 
+static const struct kernel_oplocks_ops linux_koplocks = {
+       .set_oplock             = linux_set_kernel_oplock,
+       .release_oplock         = linux_release_kernel_oplock,
+};
+
+struct kernel_oplocks *linux_init_kernel_oplocks(TALLOC_CTX *mem_ctx)
 {
-       static struct kernel_oplocks koplocks;
-        struct sigaction act;
+       struct kernel_oplocks *ctx;
+       struct tevent_signal *se;
 
        if (!linux_oplocks_available()) {
                DEBUG(3,("Linux kernel oplocks not available\n"));
                return NULL;
        }
 
-       ZERO_STRUCT(act);
-
-       act.sa_handler = NULL;
-       act.sa_sigaction = signal_handler;
-       act.sa_flags = SA_SIGINFO;
-       sigemptyset( &act.sa_mask );
-       if (sigaction(RT_SIGNAL_LEASE, &act, NULL) != 0) {
-               DEBUG(0,("Failed to setup RT_SIGNAL_LEASE handler\n"));
+       ctx = talloc_zero(mem_ctx, struct kernel_oplocks);
+       if (!ctx) {
+               DEBUG(0,("Linux Kernel oplocks talloc_Zero failed\n"));
                return NULL;
        }
 
-       koplocks.receive_message = linux_oplock_receive_message;
-       koplocks.set_oplock = linux_set_kernel_oplock;
-       koplocks.release_oplock = linux_release_kernel_oplock;
-       koplocks.msg_waiting = linux_oplock_msg_waiting;
-       koplocks.notification_fd = -1;
+       ctx->ops = &linux_koplocks;
+
+       se = tevent_add_signal(smbd_event_context(),
+                              ctx,
+                              RT_SIGNAL_LEASE, SA_SIGINFO,
+                              linux_oplock_signal_handler,
+                              ctx);
+       if (!se) {
+               DEBUG(0,("Failed to setup RT_SIGNAL_LEASE handler"));
+               TALLOC_FREE(ctx);
+               return NULL;
+       }
 
-       /* the signal can start off blocked due to a bug in bash */
-       BlockSignals(False, RT_SIGNAL_LEASE);
+       ctx->private_data = se;
 
        DEBUG(3,("Linux kernel oplocks enabled\n"));
 
-       return &koplocks;
+       return ctx;
 }
 #else
  void oplock_linux_dummy(void);