Move c_src dirs back to toplevel

[bcachefs-tools-debian] / libbcachefs / fs-io-pagecache.h

diff --git a/libbcachefs/fs-io-pagecache.h b/libbcachefs/fs-io-pagecache.h
new file mode 100644 (file)
index 0000000..27f712a
--- /dev/null
+++ b/libbcachefs/fs-io-pagecache.h
@@ -0,0 +1,176 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _BCACHEFS_FS_IO_PAGECACHE_H
+#define _BCACHEFS_FS_IO_PAGECACHE_H
+
+#include <linux/pagemap.h>
+
+typedef DARRAY(struct folio *) folios;
+
+int bch2_filemap_get_contig_folios_d(struct address_space *, loff_t,
+                                    u64, fgf_t, gfp_t, folios *);
+int bch2_write_invalidate_inode_pages_range(struct address_space *, loff_t, loff_t);
+
+/*
+ * Use u64 for the end pos and sector helpers because if the folio covers the
+ * max supported range of the mapping, the start offset of the next folio
+ * overflows loff_t. This breaks much of the range based processing in the
+ * buffered write path.
+ */
+static inline u64 folio_end_pos(struct folio *folio)
+{
+       return folio_pos(folio) + folio_size(folio);
+}
+
+static inline size_t folio_sectors(struct folio *folio)
+{
+       return PAGE_SECTORS << folio_order(folio);
+}
+
+static inline loff_t folio_sector(struct folio *folio)
+{
+       return folio_pos(folio) >> 9;
+}
+
+static inline u64 folio_end_sector(struct folio *folio)
+{
+       return folio_end_pos(folio) >> 9;
+}
+
+#define BCH_FOLIO_SECTOR_STATE()       \
+       x(unallocated)                  \
+       x(reserved)                     \
+       x(dirty)                        \
+       x(dirty_reserved)               \
+       x(allocated)
+
+enum bch_folio_sector_state {
+#define x(n)   SECTOR_##n,
+       BCH_FOLIO_SECTOR_STATE()
+#undef x
+};
+
+struct bch_folio_sector {
+       /* Uncompressed, fully allocated replicas (or on disk reservation): */
+       unsigned                nr_replicas:4;
+
+       /* Owns PAGE_SECTORS * replicas_reserved sized in memory reservation: */
+       unsigned                replicas_reserved:4;
+
+       /* i_sectors: */
+       enum bch_folio_sector_state state:8;
+};
+
+struct bch_folio {
+       spinlock_t              lock;
+       atomic_t                write_count;
+       /*
+        * Is the sector state up to date with the btree?
+        * (Not the data itself)
+        */
+       bool                    uptodate;
+       struct bch_folio_sector s[];
+};
+
+/* Helper for when we need to add debug instrumentation: */
+static inline void bch2_folio_sector_set(struct folio *folio,
+                            struct bch_folio *s,
+                            unsigned i, unsigned n)
+{
+       s->s[i].state = n;
+}
+
+/* file offset (to folio offset) to bch_folio_sector index */
+static inline int folio_pos_to_s(struct folio *folio, loff_t pos)
+{
+       u64 f_offset = pos - folio_pos(folio);
+
+       BUG_ON(pos < folio_pos(folio) || pos >= folio_end_pos(folio));
+       return f_offset >> SECTOR_SHIFT;
+}
+
+/* for newly allocated folios: */
+static inline void __bch2_folio_release(struct folio *folio)
+{
+       kfree(folio_detach_private(folio));
+}
+
+static inline void bch2_folio_release(struct folio *folio)
+{
+       EBUG_ON(!folio_test_locked(folio));
+       __bch2_folio_release(folio);
+}
+
+static inline struct bch_folio *__bch2_folio(struct folio *folio)
+{
+       return folio_has_private(folio)
+               ? (struct bch_folio *) folio_get_private(folio)
+               : NULL;
+}
+
+static inline struct bch_folio *bch2_folio(struct folio *folio)
+{
+       EBUG_ON(!folio_test_locked(folio));
+
+       return __bch2_folio(folio);
+}
+
+struct bch_folio *__bch2_folio_create(struct folio *, gfp_t);
+struct bch_folio *bch2_folio_create(struct folio *, gfp_t);
+
+struct bch2_folio_reservation {
+       struct disk_reservation disk;
+       struct quota_res        quota;
+};
+
+static inline unsigned inode_nr_replicas(struct bch_fs *c, struct bch_inode_info *inode)
+{
+       /* XXX: this should not be open coded */
+       return inode->ei_inode.bi_data_replicas
+               ? inode->ei_inode.bi_data_replicas - 1
+               : c->opts.data_replicas;
+}
+
+static inline void bch2_folio_reservation_init(struct bch_fs *c,
+                       struct bch_inode_info *inode,
+                       struct bch2_folio_reservation *res)
+{
+       memset(res, 0, sizeof(*res));
+
+       res->disk.nr_replicas = inode_nr_replicas(c, inode);
+}
+
+int bch2_folio_set(struct bch_fs *, subvol_inum, struct folio **, unsigned);
+void bch2_bio_page_state_set(struct bio *, struct bkey_s_c);
+
+void bch2_mark_pagecache_unallocated(struct bch_inode_info *, u64, u64);
+void bch2_mark_pagecache_reserved(struct bch_inode_info *, u64, u64);
+
+int bch2_get_folio_disk_reservation(struct bch_fs *,
+                               struct bch_inode_info *,
+                               struct folio *, bool);
+
+void bch2_folio_reservation_put(struct bch_fs *,
+                       struct bch_inode_info *,
+                       struct bch2_folio_reservation *);
+int bch2_folio_reservation_get(struct bch_fs *,
+                       struct bch_inode_info *,
+                       struct folio *,
+                       struct bch2_folio_reservation *,
+                       unsigned, unsigned);
+
+void bch2_set_folio_dirty(struct bch_fs *,
+                         struct bch_inode_info *,
+                         struct folio *,
+                         struct bch2_folio_reservation *,
+                         unsigned, unsigned);
+
+vm_fault_t bch2_page_fault(struct vm_fault *);
+vm_fault_t bch2_page_mkwrite(struct vm_fault *);
+void bch2_invalidate_folio(struct folio *, size_t, size_t);
+bool bch2_release_folio(struct folio *, gfp_t);
+
+loff_t bch2_seek_pagecache_data(struct inode *, loff_t, loff_t, unsigned, bool);
+loff_t bch2_seek_pagecache_hole(struct inode *, loff_t, loff_t, unsigned, bool);
+int bch2_clamp_data_hole(struct inode *, u64 *, u64 *, unsigned, bool);
+
+#endif /* _BCACHEFS_FS_IO_PAGECACHE_H */