diff --git a/fs/fuse/Kconfig b/fs/fuse/Kconfig index ca215a3cba3e..a774166264de 100644 --- a/fs/fuse/Kconfig +++ b/fs/fuse/Kconfig @@ -2,6 +2,7 @@ config FUSE_FS tristate "FUSE (Filesystem in Userspace) support" select FS_POSIX_ACL + select FS_IOMAP help With FUSE it is possible to implement a fully functional filesystem in a userspace program. diff --git a/fs/fuse/file.c b/fs/fuse/file.c index f102afc03359..ee6b7c7adba1 100644 --- a/fs/fuse/file.c +++ b/fs/fuse/file.c @@ -21,6 +21,7 @@ #include #include #include +#include static int fuse_send_open(struct fuse_mount *fm, u64 nodeid, unsigned int open_flags, int opcode, @@ -788,12 +789,16 @@ static void fuse_short_read(struct inode *inode, u64 attr_ver, size_t num_read, } } -static int fuse_do_readfolio(struct file *file, struct folio *folio) +static int fuse_do_readfolio(struct file *file, struct folio *folio, + size_t off, size_t len) { struct inode *inode = folio->mapping->host; struct fuse_mount *fm = get_fuse_mount(inode); - loff_t pos = folio_pos(folio); - struct fuse_folio_desc desc = { .length = folio_size(folio) }; + loff_t pos = folio_pos(folio) + off; + struct fuse_folio_desc desc = { + .offset = off, + .length = len, + }; struct fuse_io_args ia = { .ap.args.page_zeroing = true, .ap.args.out_pages = true, @@ -820,8 +825,6 @@ static int fuse_do_readfolio(struct file *file, struct folio *folio) if (res < desc.length) fuse_short_read(inode, attr_ver, res, &ia.ap); - folio_mark_uptodate(folio); - return 0; } @@ -834,13 +837,26 @@ static int fuse_read_folio(struct file *file, struct folio *folio) if (fuse_is_bad(inode)) goto out; - err = fuse_do_readfolio(file, folio); + err = fuse_do_readfolio(file, folio, 0, folio_size(folio)); + if (!err) + folio_mark_uptodate(folio); + fuse_invalidate_atime(inode); out: folio_unlock(folio); return err; } +static int fuse_iomap_read_folio_range(const struct iomap_iter *iter, + struct folio *folio, loff_t pos, + size_t len) +{ + struct file *file = iter->private; + size_t off = offset_in_folio(folio, pos); + + return fuse_do_readfolio(file, folio, off, len); +} + static void fuse_readpages_end(struct fuse_mount *fm, struct fuse_args *args, int err) { @@ -1375,6 +1391,24 @@ static void fuse_dio_unlock(struct kiocb *iocb, bool exclusive) } } +static const struct iomap_write_ops fuse_iomap_write_ops = { + .read_folio_range = fuse_iomap_read_folio_range, +}; + +static int fuse_iomap_begin(struct inode *inode, loff_t offset, loff_t length, + unsigned int flags, struct iomap *iomap, + struct iomap *srcmap) +{ + iomap->type = IOMAP_MAPPED; + iomap->length = length; + iomap->offset = offset; + return 0; +} + +static const struct iomap_ops fuse_iomap_ops = { + .iomap_begin = fuse_iomap_begin, +}; + static ssize_t fuse_cache_write_iter(struct kiocb *iocb, struct iov_iter *from) { struct file *file = iocb->ki_filp; @@ -1384,6 +1418,7 @@ static ssize_t fuse_cache_write_iter(struct kiocb *iocb, struct iov_iter *from) struct inode *inode = mapping->host; ssize_t err, count; struct fuse_conn *fc = get_fuse_conn(inode); + bool writeback = false; if (fc->writeback_cache) { /* Update size (EOF optimization) and mode (SUID clearing) */ @@ -1392,16 +1427,11 @@ static ssize_t fuse_cache_write_iter(struct kiocb *iocb, struct iov_iter *from) if (err) return err; - if (fc->handle_killpriv_v2 && - setattr_should_drop_suidgid(idmap, - file_inode(file))) { - goto writethrough; - } - - return generic_file_write_iter(iocb, from); + if (!fc->handle_killpriv_v2 || + !setattr_should_drop_suidgid(idmap, file_inode(file))) + writeback = true; } -writethrough: inode_lock(inode); err = count = generic_write_checks(iocb, from); @@ -1420,6 +1450,15 @@ writethrough: goto out; written = direct_write_fallback(iocb, from, written, fuse_perform_write(iocb, from)); + } else if (writeback) { + /* + * Use iomap so that we can do granular uptodate reads + * and granular dirty tracking for large folios. + */ + written = iomap_file_buffered_write(iocb, from, + &fuse_iomap_ops, + &fuse_iomap_write_ops, + file); } else { written = fuse_perform_write(iocb, from); } @@ -2209,84 +2248,6 @@ out: return err; } -/* - * It's worthy to make sure that space is reserved on disk for the write, - * but how to implement it without killing performance need more thinking. - */ -static int fuse_write_begin(struct file *file, struct address_space *mapping, - loff_t pos, unsigned len, struct folio **foliop, void **fsdata) -{ - pgoff_t index = pos >> PAGE_SHIFT; - struct fuse_conn *fc = get_fuse_conn(file_inode(file)); - struct folio *folio; - loff_t fsize; - int err = -ENOMEM; - - WARN_ON(!fc->writeback_cache); - - folio = __filemap_get_folio(mapping, index, FGP_WRITEBEGIN, - mapping_gfp_mask(mapping)); - if (IS_ERR(folio)) - goto error; - - if (folio_test_uptodate(folio) || len >= folio_size(folio)) - goto success; - /* - * Check if the start of this folio comes after the end of file, - * in which case the readpage can be optimized away. - */ - fsize = i_size_read(mapping->host); - if (fsize <= folio_pos(folio)) { - size_t off = offset_in_folio(folio, pos); - if (off) - folio_zero_segment(folio, 0, off); - goto success; - } - err = fuse_do_readfolio(file, folio); - if (err) - goto cleanup; -success: - *foliop = folio; - return 0; - -cleanup: - folio_unlock(folio); - folio_put(folio); -error: - return err; -} - -static int fuse_write_end(struct file *file, struct address_space *mapping, - loff_t pos, unsigned len, unsigned copied, - struct folio *folio, void *fsdata) -{ - struct inode *inode = folio->mapping->host; - - /* Haven't copied anything? Skip zeroing, size extending, dirtying. */ - if (!copied) - goto unlock; - - pos += copied; - if (!folio_test_uptodate(folio)) { - /* Zero any unwritten bytes at the end of the page */ - size_t endoff = pos & ~PAGE_MASK; - if (endoff) - folio_zero_segment(folio, endoff, PAGE_SIZE); - folio_mark_uptodate(folio); - } - - if (pos > inode->i_size) - i_size_write(inode, pos); - - folio_mark_dirty(folio); - -unlock: - folio_unlock(folio); - folio_put(folio); - - return copied; -} - static int fuse_launder_folio(struct folio *folio) { int err = 0; @@ -3145,11 +3106,10 @@ static const struct address_space_operations fuse_file_aops = { .writepages = fuse_writepages, .launder_folio = fuse_launder_folio, .dirty_folio = filemap_dirty_folio, + .release_folio = iomap_release_folio, .migrate_folio = filemap_migrate_folio, .bmap = fuse_bmap, .direct_IO = fuse_direct_IO, - .write_begin = fuse_write_begin, - .write_end = fuse_write_end, }; void fuse_init_file_inode(struct inode *inode, unsigned int flags)