diff options
Diffstat (limited to 'source3/smbd/notify_kernel.c')
-rw-r--r-- | source3/smbd/notify_kernel.c | 109 |
1 files changed, 71 insertions, 38 deletions
diff --git a/source3/smbd/notify_kernel.c b/source3/smbd/notify_kernel.c index 19ea41e195..8454917163 100644 --- a/source3/smbd/notify_kernel.c +++ b/source3/smbd/notify_kernel.c @@ -1,5 +1,6 @@ /* - Unix SMB/CIFS implementation. + Unix SMB/Netbios implementation. + Version 3.0 change notify handling - linux kernel based implementation Copyright (C) Andrew Tridgell 2000 @@ -22,9 +23,9 @@ #if HAVE_KERNEL_CHANGE_NOTIFY -static VOLATILE sig_atomic_t fd_pending; -static VOLATILE sig_atomic_t signals_received; -static VOLATILE sig_atomic_t signals_processed; +#define FD_PENDING_SIZE 20 +static SIG_ATOMIC_T fd_pending_array[FD_PENDING_SIZE]; +static SIG_ATOMIC_T signals_received; #ifndef DN_ACCESS #define DN_ACCESS 0x00000001 /* File accessed in directory */ @@ -53,84 +54,114 @@ static VOLATILE sig_atomic_t signals_processed; This is the structure to keep the information needed to determine if a directory has changed. *****************************************************************************/ + struct change_data { int directory_handle; }; /**************************************************************************** -the signal handler for change notify + The signal handler for change notify. + The Linux kernel has a bug in that we should be able to block any + further delivery of RT signals until the kernel_check_notify() function + unblocks them, but it seems that any signal mask we're setting here is + being overwritten on exit from this handler. I should create a standalone + test case for the kernel hackers. JRA. *****************************************************************************/ + static void signal_handler(int sig, siginfo_t *info, void *unused) { - BlockSignals(True, sig); - fd_pending = (sig_atomic_t)info->si_fd; - signals_received++; + 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(); } - - /**************************************************************************** Check if a change notify should be issued. time non-zero means timeout check (used for hash). Ignore this (async method where time is zero will be used instead). *****************************************************************************/ + static BOOL kernel_check_notify(connection_struct *conn, uint16 vuid, char *path, uint32 flags, void *datap, time_t t) { struct change_data *data = (struct change_data *)datap; + int i; + BOOL ret = False; if (t) return False; - if (data->directory_handle != (int)fd_pending) return False; - - DEBUG(3,("kernel change notify on %s fd=%d\n", path, (int)fd_pending)); - - close((int)fd_pending); - fd_pending = (sig_atomic_t)-1; - data->directory_handle = -1; - signals_processed++; + BlockSignals(True, RT_SIGNAL_NOTIFY); + for (i = 0; i < signals_received; i++) { + if (data->directory_handle == (int)fd_pending_array[i]) { + DEBUG(3,("kernel_check_notify: kernel change notify on %s fd[%d]=%d (signals_received=%d)\n", + path, i, (int)fd_pending_array[i], (int)signals_received )); + + close((int)fd_pending_array[i]); + fd_pending_array[i] = (SIG_ATOMIC_T)-1; + if (signals_received - i - 1) { + memmove((void *)&fd_pending_array[i], (void *)&fd_pending_array[i+1], + sizeof(SIG_ATOMIC_T)*(signals_received-i-1)); + } + data->directory_handle = -1; + signals_received--; + ret = True; + break; + } + } BlockSignals(False, RT_SIGNAL_NOTIFY); - return True; + return ret; } /**************************************************************************** -remove a change notify data structure + Remove a change notify data structure. *****************************************************************************/ + static void kernel_remove_notify(void *datap) { struct change_data *data = (struct change_data *)datap; int fd = data->directory_handle; if (fd != -1) { - if (fd == (int)fd_pending) { - fd_pending = (sig_atomic_t)-1; - signals_processed++; - BlockSignals(False, RT_SIGNAL_NOTIFY); + int i; + BlockSignals(True, RT_SIGNAL_NOTIFY); + for (i = 0; i < signals_received; i++) { + if (fd == (int)fd_pending_array[i]) { + close(fd); + fd_pending_array[i] = (SIG_ATOMIC_T)-1; + if (signals_received - i - 1) { + memmove((void *)&fd_pending_array[i], (void *)&fd_pending_array[i+1], + sizeof(SIG_ATOMIC_T)*(signals_received-i-1)); + } + data->directory_handle = -1; + signals_received--; + break; + } } - close(fd); + BlockSignals(False, RT_SIGNAL_NOTIFY); } SAFE_FREE(data); - DEBUG(3,("removed kernel change notify fd=%d\n", fd)); + DEBUG(3,("kernel_remove_notify: fd=%d\n", fd)); } - /**************************************************************************** -register a change notify request + Register a change notify request. *****************************************************************************/ + static void *kernel_register_notify(connection_struct *conn, char *path, uint32 flags) { struct change_data data; int fd; unsigned long kernel_flags; - fd = conn->vfs_ops.open(conn, path, O_RDONLY, 0); + fd = sys_open(path,O_RDONLY, 0); if (fd == -1) { DEBUG(3,("Failed to open directory %s for change notify\n", path)); return NULL; } - if (fcntl(fd, F_SETSIG, RT_SIGNAL_NOTIFY) == -1) { + if (sys_fcntl_long(fd, F_SETSIG, RT_SIGNAL_NOTIFY) == -1) { DEBUG(3,("Failed to set signal handler for change notify\n")); return NULL; } @@ -147,7 +178,7 @@ static void *kernel_register_notify(connection_struct *conn, char *path, uint32 if (flags & FILE_NOTIFY_CHANGE_EA) kernel_flags |= DN_ATTRIB; if (flags & FILE_NOTIFY_CHANGE_FILE_NAME) kernel_flags |= DN_RENAME|DN_DELETE; - if (fcntl(fd, F_NOTIFY, kernel_flags) == -1) { + if (sys_fcntl_long(fd, F_NOTIFY, kernel_flags) == -1) { DEBUG(3,("Failed to set async flag for change notify\n")); return NULL; } @@ -161,22 +192,24 @@ static void *kernel_register_notify(connection_struct *conn, char *path, uint32 } /**************************************************************************** -see if the kernel supports change notify + See if the kernel supports change notify. ****************************************************************************/ + static BOOL kernel_notify_available(void) { int fd, ret; fd = open("/tmp", O_RDONLY); - if (fd == -1) return False; /* uggh! */ - ret = fcntl(fd, F_NOTIFY, 0); + if (fd == -1) + return False; /* uggh! */ + ret = sys_fcntl_long(fd, F_NOTIFY, 0); close(fd); return ret == 0; } - /**************************************************************************** -setup kernel based change notify + Setup kernel based change notify. ****************************************************************************/ + struct cnotify_fns *kernel_notify_init(void) { static struct cnotify_fns cnotify; @@ -190,7 +223,8 @@ struct cnotify_fns *kernel_notify_init(void) return NULL; } - if (!kernel_notify_available()) return NULL; + if (!kernel_notify_available()) + return NULL; cnotify.register_notify = kernel_register_notify; cnotify.check_notify = kernel_check_notify; @@ -200,7 +234,6 @@ struct cnotify_fns *kernel_notify_init(void) return &cnotify; } - #else void notify_kernel_dummy(void) {} #endif /* HAVE_KERNEL_CHANGE_NOTIFY */ |