1 /* 2 * File-specific pager functionality. 3 * 4 * Copyright (C) 2021, 2022, 2023, 2024 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 object_flags_t _object_flags; 38 offset_t _data_current; 39 40 /* Notification endpoint for event subscription. */ 41 42 l4_cap_idx_t _notifier = L4_INVALID_CAP; 43 44 /* Resize flag for notification. */ 45 46 bool _resized = false; 47 48 /* Helper methods. */ 49 50 bool copy_on_write(); 51 52 public: 53 fileid_t fileid; 54 55 explicit FilePager(fileid_t fileid, FileProvider *provider, flags_t flags, 56 object_flags_t object_flags); 57 58 virtual void close(); 59 60 /* Server details. */ 61 62 ipc_server_default_config_type config(); 63 64 void *interface() 65 { return static_cast<MappedFileObject *>(this); } 66 67 /* Flush methods. */ 68 69 virtual long flush(offset_t position, offset_t *size); 70 71 virtual long refresh(offset_t *position, offset_t *start_pos, 72 offset_t *end_pos, offset_t *size, 73 object_flags_t *object_flags); 74 75 /* File methods. */ 76 77 virtual long reopen(flags_t flags, offset_t *size, l4_cap_idx_t *file, 78 object_flags_t *object_flags); 79 80 virtual long resize(offset_t *size); 81 82 /* Pager and mapped file methods. */ 83 84 virtual long map(offset_t offset, map_address_t hot_spot, map_flags_t flags, 85 l4_snd_fpage_t *region); 86 87 virtual long mmap(offset_t position, offset_t length, 88 offset_t start_visible, offset_t end_visible, 89 offset_t *start_pos, offset_t *end_pos, offset_t *size); 90 91 /* Notification methods. */ 92 93 virtual long subscribe(l4_cap_idx_t notifier, notify_flags_t flags); 94 95 virtual long unsubscribe(); 96 }; 97 98 // vim: tabstop=4 expandtab shiftwidth=4