1 /* SPDX-License-Identifier: GPL-2.0-or-later */ 2 /* 3 * Copyright (C) International Business Machines Corp., 2000-2002 4 * Portions Copyright (C) Christoph Hellwig, 2001-2002 5 */ 6 #ifndef _H_JFS_METAPAGE 7 #define _H_JFS_METAPAGE 8 9 #include <linux/pagemap.h> 10 11 struct metapage { 12 /* Common logsyncblk prefix (see jfs_logmgr.h) */ 13 u16 xflag; 14 u16 unused; 15 lid_t lid; 16 int lsn; 17 struct list_head synclist; 18 /* End of logsyncblk prefix */ 19 20 unsigned long flag; /* See Below */ 21 unsigned long count; /* Reference count */ 22 void *data; /* Data pointer */ 23 sector_t index; /* block address of page */ 24 wait_queue_head_t wait; 25 26 /* implementation */ 27 struct page *page; 28 struct super_block *sb; 29 unsigned int logical_size; 30 31 /* Journal management */ 32 int clsn; 33 int nohomeok; 34 struct jfs_log *log; 35 }; 36 37 /* metapage flag */ 38 #define META_locked 0 39 #define META_dirty 2 40 #define META_sync 3 41 #define META_discard 4 42 #define META_forcewrite 5 43 #define META_io 6 44 45 #define mark_metapage_dirty(mp) set_bit(META_dirty, &(mp)->flag) 46 47 /* function prototypes */ 48 extern int metapage_init(void); 49 extern void metapage_exit(void); 50 extern struct metapage *__get_metapage(struct inode *inode, 51 unsigned long lblock, unsigned int size, 52 int absolute, unsigned long new); 53 54 #define read_metapage(inode, lblock, size, absolute)\ 55 __get_metapage(inode, lblock, size, absolute, false) 56 57 #define get_metapage(inode, lblock, size, absolute)\ 58 __get_metapage(inode, lblock, size, absolute, true) 59 60 extern void release_metapage(struct metapage *); 61 extern void grab_metapage(struct metapage *); 62 extern void force_metapage(struct metapage *); 63 64 /* 65 * hold_metapage and put_metapage are used in conjunction. The page lock 66 * is not dropped between the two, so no other threads can get or release 67 * the metapage 68 */ 69 extern void hold_metapage(struct metapage *); 70 extern void put_metapage(struct metapage *); 71 write_metapage(struct metapage * mp)72 static inline void write_metapage(struct metapage *mp) 73 { 74 set_bit(META_dirty, &mp->flag); 75 release_metapage(mp); 76 } 77 flush_metapage(struct metapage * mp)78 static inline void flush_metapage(struct metapage *mp) 79 { 80 set_bit(META_sync, &mp->flag); 81 write_metapage(mp); 82 } 83 discard_metapage(struct metapage * mp)84 static inline void discard_metapage(struct metapage *mp) 85 { 86 clear_bit(META_dirty, &mp->flag); 87 set_bit(META_discard, &mp->flag); 88 release_metapage(mp); 89 } 90 metapage_nohomeok(struct metapage * mp)91 static inline void metapage_nohomeok(struct metapage *mp) 92 { 93 struct page *page = mp->page; 94 lock_page(page); 95 if (!mp->nohomeok++) { 96 mark_metapage_dirty(mp); 97 get_page(page); 98 wait_on_page_writeback(page); 99 } 100 unlock_page(page); 101 } 102 103 /* 104 * This serializes access to mp->lsn when metapages are added to logsynclist 105 * without setting nohomeok. i.e. updating imap & dmap 106 */ metapage_wait_for_io(struct metapage * mp)107 static inline void metapage_wait_for_io(struct metapage *mp) 108 { 109 if (test_bit(META_io, &mp->flag)) 110 wait_on_page_writeback(mp->page); 111 } 112 113 /* 114 * This is called when already holding the metapage 115 */ _metapage_homeok(struct metapage * mp)116 static inline void _metapage_homeok(struct metapage *mp) 117 { 118 if (!--mp->nohomeok) 119 put_page(mp->page); 120 } 121 metapage_homeok(struct metapage * mp)122 static inline void metapage_homeok(struct metapage *mp) 123 { 124 hold_metapage(mp); 125 _metapage_homeok(mp); 126 put_metapage(mp); 127 } 128 129 extern const struct address_space_operations jfs_metapage_aops; 130 131 /* 132 * This routines invalidate all pages for an extent. 133 */ 134 extern void __invalidate_metapages(struct inode *, s64, int); 135 #define invalidate_pxd_metapages(ip, pxd) \ 136 __invalidate_metapages((ip), addressPXD(&(pxd)), lengthPXD(&(pxd))) 137 #define invalidate_dxd_metapages(ip, dxd) \ 138 __invalidate_metapages((ip), addressDXD(&(dxd)), lengthDXD(&(dxd))) 139 #define invalidate_xad_metapages(ip, xad) \ 140 __invalidate_metapages((ip), addressXAD(&(xad)), lengthXAD(&(xad))) 141 142 #endif /* _H_JFS_METAPAGE */ 143