1 /* 2 * File-specific pager functionality. 3 * 4 * Copyright (C) 2021, 2022 Paul Boddie <paul@boddie.org.uk> 5 * 6 * This program is free software; you can redistribute it and/or 7 * modify it under the terms of the GNU General Public License as 8 * published by the Free Software Foundation; either version 2 of 9 * the License, or (at your option) any later version. 10 * 11 * This program is distributed in the hope that it will be useful, 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 * GNU General Public License for more details. 15 * 16 * You should have received a copy of the GNU General Public License 17 * along with this program; if not, write to the Free Software 18 * Foundation, Inc., 51 Franklin Street, Fifth Floor, 19 * Boston, MA 02110-1301, USA 20 */ 21 22 #pragma once 23 24 #include <fsserver/mapped_file_object_interface.h> 25 #include <fsserver/pager.h> 26 #include <fsserver/file_provider.h> 27 28 29 30 /* A pager abstraction for a file. */ 31 32 class FilePager : public Pager, public MappedFileObject 33 { 34 protected: 35 FileProvider *_provider; 36 flags_t _flags; 37 38 /* Notification endpoint for event subscription. */ 39 40 unsigned int _endpoint; 41 42 /* Resize flag for notification. */ 43 44 bool _resized = false; 45 46 /* Helper methods. */ 47 48 bool copy_on_write(); 49 50 public: 51 fileid_t fileid; 52 53 explicit FilePager(fileid_t fileid, FileProvider *provider, flags_t flags); 54 55 virtual void close(); 56 57 /* Server details. */ 58 59 int expected_items(); 60 61 ipc_server_handler_type handler(); 62 63 void *interface() 64 { return static_cast<MappedFileObject *>(this); } 65 66 /* File methods. */ 67 68 virtual long flush(offset_t populated_size, offset_t *size); 69 70 virtual long resize(offset_t *size); 71 72 /* Pager and mapped file methods. */ 73 74 virtual long map(offset_t offset, address_t hot_spot, map_flags_t flags, 75 l4_snd_fpage_t *region); 76 77 virtual long mmap(offset_t position, offset_t length, 78 offset_t start_visible, offset_t end_visible, 79 offset_t *start_pos, offset_t *end_pos, offset_t *size); 80 81 /* Notification methods. */ 82 83 virtual long subscribe(l4_cap_idx_t notifier, notify_flags_t flags); 84 85 virtual long unsubscribe(); 86 }; 87 88 // vim: tabstop=4 expandtab shiftwidth=4