diff options
Diffstat (limited to 'source3/locking/locking.c')
| -rw-r--r-- | source3/locking/locking.c | 641 |
1 files changed, 13 insertions, 628 deletions
diff --git a/source3/locking/locking.c b/source3/locking/locking.c index fa56e0a628..75198d6303 100644 --- a/source3/locking/locking.c +++ b/source3/locking/locking.c @@ -42,190 +42,6 @@ int global_smbpid; /* the locking database handle */ static TDB_CONTEXT *tdb; -/* - * Doubly linked list to hold pending closes needed for - * POSIX locks. This may be changed to use a hash table (as - * in lib/hash.c if this is too slow in use.... JRA. - */ - -struct pending_closes { - struct pending_closes *next; - struct pending_closes *prev; - SMB_DEV_T dev; - SMB_INO_T inode; - int num_posix_locks; - size_t fd_array_size; - int *fd_array; -}; - -static struct pending_closes *pending_close_list = NULL; - -/**************************************************************************** - Find a dev/inode pair in the pending close list. -****************************************************************************/ - -static struct pending_closes *find_pending_close_entry(SMB_DEV_T dev, SMB_INO_T inode) -{ - struct pending_closes *pc; - - for(pc = pending_close_list; pc; pc = pc->next) { - if (dev == pc->dev && inode == pc->inode) { - DLIST_PROMOTE(pending_close_list,pc); - return pc; - } - } - - return NULL; -} - -/**************************************************************************** - Add an fd into the pending close array. -****************************************************************************/ - -static BOOL add_fd_to_close_entry(struct pending_closes *pc, int fd) -{ - if ((pc->fd_array = (int *)Realloc(pc->fd_array, (pc->fd_array_size + 1)*sizeof(int))) == NULL) { - DEBUG(0,("add_fd_to_close_entry: Unable to increase fd_array !\n")); - return False; - } - - pc->fd_array[pc->fd_array_size] = fd; - pc->fd_array_size++; - - DEBUG(10,("add_fd_to_close_entry: added fd = %d, size = %u : dev = %.0f, ino = %.0f\n", - fd, (unsigned int)pc->fd_array_size, (double)pc->dev, (double)pc->inode )); - - return True; -} - -/**************************************************************************** - Deal with pending closes needed by POSIX locking support. -****************************************************************************/ - -int fd_close_posix(struct connection_struct *conn, files_struct *fsp) -{ - struct pending_closes *pc; - int saved_errno = 0; - int ret; - size_t i; - - if (!lp_posix_locking(SNUM(conn))) { - ret = conn->vfs_ops.close(fsp->fd); - fsp->fd = -1; - return ret; - } - - pc = find_pending_close_entry(fsp->dev, fsp->inode); - - if (!pc) { - /* - * No other open with a POSIX lock on this dev/inode within this smbd. - * Just close the fd. - */ - ret = conn->vfs_ops.close(fsp->fd); - fsp->fd = -1; - return ret; - } - - if (pc->num_posix_locks) { - /* - * There are outstanding locks on this dev/inode pair. - * Add our fd to the list and set fsp->fd to -1 to - * stop the close. - */ - - if (!add_fd_to_close_entry(pc, fsp->fd)) - return False; - - fsp->fd = -1; - return 0; - } - - DEBUG(10,("fd_close_posix: doing close on %u fd's.\n", (unsigned int)pc->fd_array_size )); - - /* - * This is the last close. If there are pending fd's close them - * now. Save the errno just in case. - */ - - for(i = 0; i < pc->fd_array_size; i++) { - if (pc->fd_array[i] != -1) { - if (conn->vfs_ops.close(pc->fd_array[i]) == -1) { - saved_errno = errno; - } - } - } - - if (pc->fd_array) - free((char *)pc->fd_array); - - DLIST_REMOVE(pending_close_list, pc); - - free((char *)pc); - - ret = conn->vfs_ops.close(fsp->fd); - - if (saved_errno != 0) { - errno = saved_errno; - ret = -1; - } - - fsp->fd = -1; - - return ret; -} - -/**************************************************************************** - A POSIX lock was granted. Increment the lock list count (create if needed). -****************************************************************************/ - -static void increment_posix_lock_list(files_struct *fsp) -{ - struct pending_closes *pc; - - if ((pc = find_pending_close_entry(fsp->dev, fsp->inode)) == NULL) { - if (!(pc = (struct pending_closes *)malloc(sizeof(struct pending_closes)))) { - DEBUG(0,("increment_lock_list: malloc fail.\n")); - return; - } - ZERO_STRUCTP(pc); - pc->dev = fsp->dev; - pc->inode = fsp->inode; - DLIST_ADD(pending_close_list, pc); - - DEBUG(10,("increment_posix_lock_list: creating entry for file %s: dev = %.0f, ino = %.0f\n", - fsp->fsp_name, (double)fsp->dev, (double)fsp->inode )); - } - - pc->num_posix_locks++; - - DEBUG(10,("increment_posix_lock_list: entry for file %s: dev = %.0f, ino = %.0f, num_locks = %d\n", - fsp->fsp_name, (double)pc->dev, (double)pc->inode, pc->num_posix_locks )); -} - - -/**************************************************************************** - A POSIX lock was granted. Decrement the lock list count. -****************************************************************************/ - -static void decrement_posix_lock_list(files_struct *fsp) -{ - struct pending_closes *pc; - - pc = find_pending_close_entry(fsp->dev, fsp->inode); - - if (pc == NULL) { - smb_panic("decrement_lock_list: Unlock not found !\n"); - } - - pc->num_posix_locks--; - - DEBUG(10,("decrement_posix_lock_list: entry for file %s: dev = %.0f, ino = %.0f, num_locks = %d\n", - fsp->fsp_name, (double)pc->dev, (double)pc->inode, pc->num_posix_locks )); - - SMB_ASSERT(pc->num_posix_locks >= 0); -} - /**************************************************************************** Debugging aid :-). ****************************************************************************/ @@ -236,347 +52,6 @@ static const char *lock_type_name(enum brl_type lock_type) } /**************************************************************************** - Utility function to map a lock type correctly depending on the open - mode of a file. -****************************************************************************/ - -static int map_posix_lock_type( files_struct *fsp, enum brl_type lock_type) -{ - if((lock_type == WRITE_LOCK) && !fsp->can_write) { - /* - * Many UNIX's cannot get a write lock on a file opened read-only. - * Win32 locking semantics allow this. - * Do the best we can and attempt a read-only lock. - */ - DEBUG(10,("map_posix_lock_type: Downgrading write lock to read due to read-only file.\n")); - return F_RDLCK; - } else if((lock_type == READ_LOCK) && !fsp->can_read) { - /* - * Ditto for read locks on write only files. - */ - DEBUG(10,("map_posix_lock_type: Changing read lock to write due to write-only file.\n")); - return F_WRLCK; - } - - /* - * This return should be the most normal, as we attempt - * to always open files read/write. - */ - - return (lock_type == READ_LOCK) ? F_RDLCK : F_WRLCK; -} - -/**************************************************************************** - Check to see if the given unsigned lock range is within the possible POSIX - range. Modifies the given args to be in range if possible, just returns - False if not. -****************************************************************************/ - -static BOOL posix_lock_in_range(SMB_OFF_T *offset_out, SMB_OFF_T *count_out, - SMB_BIG_UINT u_offset, SMB_BIG_UINT u_count) -{ - SMB_OFF_T offset; - SMB_OFF_T count; - -#if defined(LARGE_SMB_OFF_T) && !defined(HAVE_BROKEN_FCNTL64_LOCKS) - - SMB_OFF_T mask2 = ((SMB_OFF_T)0x4) << (SMB_OFF_T_BITS-4); - SMB_OFF_T mask = (mask2<<1); - SMB_OFF_T neg_mask = ~mask; - - /* - * In this case SMB_OFF_T is 64 bits, - * and the underlying system can handle 64 bit signed locks. - * Cast to signed type. - */ - - offset = (SMB_OFF_T)u_offset; - count = (SMB_OFF_T)u_count; - - /* - * Deal with a very common case of count of all ones. - * (lock entire file). - */ - - if(count == (SMB_OFF_T)-1) - count &= ~mask; - - /* - * POSIX lock ranges cannot be negative. - * Fail if any combination becomes negative. - */ - - if(offset < 0 || count < 0 || (offset + count < 0)) { - DEBUG(10,("posix_lock_in_range: negative range: offset = %.0f, count = %.0f. Ignoring lock.\n", - (double)offset, (double)count )); - return False; - } - - /* - * In this case SMB_OFF_T is 64 bits, the offset and count - * fit within the positive range, and the underlying - * system can handle 64 bit locks. Just return as the - * cast values are ok. - */ - -#else /* !LARGE_SMB_OFF_T || HAVE_BROKEN_FCNTL64_LOCKS */ - - /* - * In this case either SMB_OFF_T is 32 bits, - * or the underlying system cannot handle 64 bit signed locks. - * Either way we have to try and mangle to fit within 31 bits. - * This is difficult. - */ - -#if defined(HAVE_BROKEN_FCNTL64_LOCKS) - - /* - * SMB_OFF_T is 64 bits, but we need to use 31 bits due to - * broken large locking. - */ - - /* - * Deal with a very common case of count of all ones. - * (lock entire file). - */ - - if(u_count == (SMB_BIG_UINT)-1) - count = 0x7FFFFFFF; - - if(((u_offset >> 32) & 0xFFFFFFFF) || ((u_count >> 32) & 0xFFFFFFFF)) { - DEBUG(10,("posix_lock_in_range: top 32 bits not zero. offset = %.0f, count = %.0f. Ignoring lock.\n", - (double)u_offset, (double)u_count )); - /* Top 32 bits of offset or count were not zero. */ - return False; - } - - /* Cast from 64 bits unsigned to 64 bits signed. */ - offset = (SMB_OFF_T)u_offset; - count = (SMB_OFF_T)u_count; - - /* - * Check if we are within the 2^31 range. - */ - - { - int32 low_offset = (int32)offset; - int32 low_count = (int32)count; - - if(low_offset < 0 || low_count < 0 || (low_offset + low_count < 0)) { - DEBUG(10,("posix_lock_in_range: not within 2^31 range. low_offset = %d, low_count = %d. Ignoring lock.\n", - low_offset, low_count )); - return False; - } - } - - /* - * Ok - we can map from a 64 bit number to a 31 bit lock. - */ - -#else /* HAVE_BROKEN_FCNTL64_LOCKS */ - - /* - * SMB_OFF_T is 32 bits. - */ - -#if defined(HAVE_LONGLONG) - - /* - * SMB_BIG_UINT is 64 bits, we can do a 32 bit shift. - */ - - /* - * Deal with a very common case of count of all ones. - * (lock entire file). - */ - - if(u_count == (SMB_BIG_UINT)-1) - count = 0x7FFFFFFF; - - if(((u_offset >> 32) & 0xFFFFFFFF) || ((u_count >> 32) & 0xFFFFFFFF)) { - DEBUG(10,("posix_lock_in_range: top 32 bits not zero. u_offset = %.0f, u_count = %.0f. Ignoring lock.\n", - (double)u_offset, (double)u_count )); - return False; - } - - /* Cast from 64 bits unsigned to 32 bits signed. */ - offset = (SMB_OFF_T)u_offset; - count = (SMB_OFF_T)u_count; - - /* - * Check if we are within the 2^31 range. - */ - - if(offset < 0 || count < 0 || (offset + count < 0)) { - DEBUG(10,("posix_lock_in_range: not within 2^31 range. offset = %d, count = %d. Ignoring lock.\n", - (int)offset, (int)count )); - return False; - } - -#else /* HAVE_LONGLONG */ - - /* - * SMB_BIG_UINT and SMB_OFF_T are both 32 bits, - * just cast. - */ - - /* - * Deal with a very common case of count of all ones. - * (lock entire file). - */ - - if(u_count == (SMB_BIG_UINT)-1) - count = 0x7FFFFFFF; - - /* Cast from 32 bits unsigned to 32 bits signed. */ - offset = (SMB_OFF_T)u_offset; - count = (SMB_OFF_T)u_count; - - /* - * Check if we are within the 2^31 range. - */ - - if(offset < 0 || count < 0 || (offset + count < 0)) { - DEBUG(10,("posix_lock_in_range: not within 2^31 range. offset = %d, count = %d. Ignoring lock.\n", - (int)offset, (int)count )); - return False; - } - -#endif /* HAVE_LONGLONG */ -#endif /* LARGE_SMB_OFF_T */ -#endif /* !LARGE_SMB_OFF_T || HAVE_BROKEN_FCNTL64_LOCKS */ - - /* - * The mapping was successful. - */ - - DEBUG(10,("posix_lock_in_range: offset_out = %.0f, count_out = %.0f\n", - (double)offset, (double)count )); - - *offset_out = offset; - *count_out = count; - - return True; -} - -/**************************************************************************** - POSIX function to see if a file region is locked. Returns True if the - region is locked, False otherwise. -****************************************************************************/ - -static BOOL is_posix_locked(files_struct *fsp, SMB_BIG_UINT u_offset, SMB_BIG_UINT u_count, enum brl_type lock_type) -{ - SMB_OFF_T offset; - SMB_OFF_T count; - - DEBUG(10,("is_posix_locked: File %s, offset = %.0f, count = %.0f, type = %s\n", - fsp->fsp_name, (double)u_offset, (double)u_count, lock_type_name(lock_type) )); - - /* - * If the requested lock won't fit in the POSIX range, we will - * never set it, so presume it is not locked. - */ - - if(!posix_lock_in_range(&offset, &count, u_offset, u_count)) - return False; - - /* - * Note that most UNIX's can *test* for a write lock on - * a read-only fd, just not *set* a write lock on a read-only - * fd. So we don't need to use map_lock_type here. - */ - - return fcntl_lock(fsp->fd,SMB_F_GETLK,offset,count,lock_type); -} - -/**************************************************************************** - POSIX function to acquire a lock. Returns True if the - lock could be granted, False if not. -****************************************************************************/ - -static BOOL set_posix_lock(files_struct *fsp, SMB_BIG_UINT u_offset, SMB_BIG_UINT u_count, enum brl_type lock_type) -{ - SMB_OFF_T offset; - SMB_OFF_T count; - BOOL ret = True; - - DEBUG(5,("set_posix_lock: File %s, offset = %.0f, count = %.0f, type = %s\n", - fsp->fsp_name, (double)u_offset, (double)u_count, lock_type_name(lock_type) )); - - /* - * If the requested lock won't fit in the POSIX range, we will - * pretend it was successful. - */ - - if(!posix_lock_in_range(&offset, &count, u_offset, u_count)) { - increment_posix_lock_list(fsp); - return True; - } - - /* - * Note that setting multiple overlapping read locks on different - * file descriptors will not be held separately by the kernel (POSIX - * braindamage), but will be merged into one continuous read lock - * range. We cope with this case in the release_posix_lock code - * below. JRA. - */ - - ret = fcntl_lock(fsp->fd,SMB_F_SETLK,offset,count,map_posix_lock_type(fsp,lock_type)); - - if (ret) - increment_posix_lock_list(fsp); - - return ret; -} - -/**************************************************************************** - POSIX function to release a lock given a list. Returns True if the - lock could be released, False if not. -****************************************************************************/ - -static BOOL release_posix_lock(files_struct *fsp, struct unlock_list *ulist) -{ - BOOL ret = True; - - for(; ulist; ulist = ulist->next) { - SMB_OFF_T offset = ulist->start; - SMB_OFF_T count = ulist->size; - - DEBUG(5,("release_posix_lock: File %s, offset = %.0f, count = %.0f\n", - fsp->fsp_name, (double)offset, (double)count )); - - if(count == 0) { - - /* - * This lock must overlap with an existing read-only lock - * held by another fd. Don't do any POSIX call. - */ - - continue; - } - - /* - * If the requested lock won't fit in the POSIX range, we will - * pretend it was successful. - */ - - if(!posix_lock_in_range(&offset, &count, offset, count)) - continue; - - ret = fcntl_lock(fsp->fd,SMB_F_SETLK,offset,count,F_UNLCK); - } - - /* - * We treat this as one unlock request for POSIX accounting purposes even - * if it may have been split into multiple smaller POSIX unlock ranges. - */ - - decrement_posix_lock_list(fsp); - - return ret; -} - -/**************************************************************************** Utility function called to see if a file region is locked. ****************************************************************************/ @@ -675,10 +150,6 @@ BOOL do_unlock(files_struct *fsp,connection_struct *conn, int *eclass,uint32 *ecode) { BOOL ok = False; - TALLOC_CTX *ul_ctx = NULL; - struct unlock_list *ulist = NULL; - struct unlock_list *ul = NULL; - pid_t pid; if (!lp_locking(SNUM(conn))) return(True); @@ -698,10 +169,8 @@ BOOL do_unlock(files_struct *fsp,connection_struct *conn, * match then don't bother looking to remove POSIX locks. */ - pid = getpid(); - ok = brl_unlock(fsp->dev, fsp->inode, fsp->fnum, - global_smbpid, pid, conn->cnum, offset, count); + global_smbpid, getpid(), conn->cnum, offset, count); if (!ok) { DEBUG(10,("do_unlock: returning ERRlock.\n" )); @@ -713,47 +182,7 @@ BOOL do_unlock(files_struct *fsp,connection_struct *conn, if (!lp_posix_locking(SNUM(conn))) return True; - if ((ul_ctx = talloc_init()) == NULL) { - DEBUG(0,("do_unlock: unable to init talloc context.\n")); - return True; /* Not a fatal error. */ - } - - if ((ul = (struct unlock_list *)talloc(ul_ctx, sizeof(struct unlock_list))) == NULL) { - DEBUG(0,("do_unlock: unable to talloc unlock list.\n")); - talloc_destroy(ul_ctx); - return True; /* Not a fatal error. */ - } - - /* - * Create the initial list entry containing the - * lock we want to remove. - */ - - ZERO_STRUCTP(ul); - ul->start = offset; - ul->size = count; - ul->smbpid = global_smbpid; - - DLIST_ADD(ulist, ul); - - /* - * The following call calculates if there are any - * overlapping read locks held by this process on - * other fd's open on the same file and creates a - * list of unlock ranges that will allow other - * POSIX lock ranges to remain on the file whilst the - * unlocks are performed. - */ - - ulist = brl_unlock_list(ul_ctx, ulist, pid, fsp->dev, fsp->inode); - - /* - * Release the POSIX locks on the list of ranges returned. - */ - - (void)release_posix_lock(fsp, ulist); - - talloc_destroy(ul_ctx); + (void)release_posix_lock(fsp, offset, count); return True; /* Did unlock */ } @@ -769,66 +198,19 @@ void locking_close_file(files_struct *fsp) if (!lp_locking(SNUM(fsp->conn))) return; - if(lp_posix_locking(SNUM(fsp->conn))) { - - TALLOC_CTX *ul_ctx = NULL; - struct unlock_list *ul = NULL; - int eclass; - uint32 ecode; - struct pending_closes *pc; - - /* - * Optimization for the common case where we are the only - * opener of a file. If all fd entries are our own, we don't - * need to explicitly release all the locks via the POSIX functions, - * we can just release all the brl locks, as in the no POSIX locking case. - */ - - if ((pc = find_pending_close_entry(fsp->dev, fsp->inode)) != NULL) { - - if (pc->fd_array_size == 1 && pc->fd_array[0] == fsp->fd ) { - /* - * Just release all the brl locks, no need to release individually. - */ - - brl_close(fsp->dev, fsp->inode, pid, fsp->conn->cnum, fsp->fnum); - return; - } - } - - if ((ul_ctx = talloc_init()) == NULL) { - DEBUG(0,("locking_close_file: unable to init talloc context.\n")); - return; - } - - /* - * We need to release all POSIX locks we have on this - * fd. Get all our existing locks from the tdb locking database. - */ - - ul = brl_getlocklist(ul_ctx, fsp->dev, fsp->inode, pid, fsp->conn->cnum, fsp->fnum); - - /* - * Now unlock all of them. This will remove the brl entry also - * for each lock. Note we need to make sure the global_smbpid matches - * the one associated with each lock in case the client plays games - * with smbpids (like smbtorture does :-). - */ + /* + * Just release all the brl locks, no need to release individually. + */ - for(; ul; ul = ul->next) { - global_smbpid = ul->smbpid; - do_unlock(fsp,fsp->conn,ul->size,ul->start,&eclass,&ecode); - } - - talloc_destroy(ul_ctx); + brl_close(fsp->dev, fsp->inode, pid, fsp->conn->cnum, fsp->fnum); - } else { + if(lp_posix_locking(SNUM(fsp->conn))) { - /* - * Just release all the brl locks, no need to release individually. + /* + * Release all the POSIX locks. */ + posix_locking_close_file(fsp); - brl_close(fsp->dev, fsp->inode, pid, fsp->conn->cnum, fsp->fnum); } } @@ -851,6 +233,9 @@ BOOL locking_init(int read_only) return False; } + if (!posix_locking_init()) + return False; + return True; } |