NETFS_DOWNLOAD_FROM_SERVER,
NETFS_READ_FROM_CACHE,
NETFS_INVALID_READ,
+ NETFS_UPLOAD_TO_SERVER,
+ NETFS_WRITE_TO_CACHE,
+ NETFS_INVALID_WRITE,
} __mode(byte);
typedef void (*netfs_io_terminated_t)(void *priv, ssize_t transferred_or_error,
struct fscache_cookie *cache;
#endif
loff_t remote_i_size; /* Size of the remote file */
+ loff_t zero_point; /* Size after which we assume there's no data
+ * on the server */
unsigned long flags;
#define NETFS_ICTX_ODIRECT 0 /* The file has DIO in progress */
+#define NETFS_ICTX_UNBUFFERED 1 /* I/O should not use the pagecache */
+#define NETFS_ICTX_WRITETHROUGH 2 /* Write-through caching */
+#define NETFS_ICTX_NO_WRITE_STREAMING 3 /* Don't engage in write-streaming */
};
+/*
+ * A netfs group - for instance a ceph snap. This is marked on dirty pages and
+ * pages marked with a group must be flushed before they can be written under
+ * the domain of another group.
+ */
+struct netfs_group {
+ refcount_t ref;
+ void (*free)(struct netfs_group *netfs_group);
+};
+
+/*
+ * Information about a dirty page (attached only if necessary).
+ * folio->private
+ */
+struct netfs_folio {
+ struct netfs_group *netfs_group; /* Filesystem's grouping marker (or NULL). */
+ unsigned int dirty_offset; /* Write-streaming dirty data offset */
+ unsigned int dirty_len; /* Write-streaming dirty data length */
+};
+#define NETFS_FOLIO_INFO 0x1UL /* OR'd with folio->private. */
+
+static inline struct netfs_folio *netfs_folio_info(struct folio *folio)
+{
+ void *priv = folio_get_private(folio);
+
+ if ((unsigned long)priv & NETFS_FOLIO_INFO)
+ return (struct netfs_folio *)((unsigned long)priv & ~NETFS_FOLIO_INFO);
+ return NULL;
+}
+
+static inline struct netfs_group *netfs_folio_group(struct folio *folio)
+{
+ struct netfs_folio *finfo;
+ void *priv = folio_get_private(folio);
+
+ finfo = netfs_folio_info(folio);
+ if (finfo)
+ return finfo->netfs_group;
+ return priv;
+}
+
/*
* Resources required to do operations on a cache.
*/
};
/*
- * Descriptor for a single component subrequest.
+ * Descriptor for a single component subrequest. Each operation represents an
+ * individual read/write from/to a server, a cache, a journal, etc..
+ *
+ * The buffer iterator is persistent for the life of the subrequest struct and
+ * the pages it points to can be relied on to exist for the duration.
*/
struct netfs_io_subrequest {
struct netfs_io_request *rreq; /* Supervising I/O request */
+ struct work_struct work;
struct list_head rreq_link; /* Link in rreq->subrequests */
struct iov_iter io_iter; /* Iterator for this subrequest */
loff_t start; /* Where to start the I/O */
NETFS_READAHEAD, /* This read was triggered by readahead */
NETFS_READPAGE, /* This read is a synchronous read */
NETFS_READ_FOR_WRITE, /* This read is to prepare a write */
+ NETFS_WRITEBACK, /* This write was triggered by writepages */
+ NETFS_WRITETHROUGH, /* This write was made by netfs_perform_write() */
+ NETFS_LAUNDER_WRITE, /* This is triggered by ->launder_folio() */
+ NETFS_UNBUFFERED_WRITE, /* This is an unbuffered write */
+ NETFS_DIO_READ, /* This is a direct I/O read */
+ NETFS_DIO_WRITE, /* This is a direct I/O write */
+ nr__netfs_io_origin
} __mode(byte);
/*
};
struct inode *inode; /* The file being accessed */
struct address_space *mapping; /* The mapping being accessed */
+ struct kiocb *iocb; /* AIO completion vector */
struct netfs_cache_resources cache_resources;
struct list_head proc_link; /* Link in netfs_iorequests */
struct list_head subrequests; /* Contributory I/O operations */
struct bio_vec *direct_bv; /* DIO buffer list (when handling iovec-iter) */
unsigned int direct_bv_count; /* Number of elements in direct_bv[] */
unsigned int debug_id;
+ unsigned int rsize; /* Maximum read size (0 for none) */
+ unsigned int wsize; /* Maximum write size (0 for none) */
+ unsigned int subreq_counter; /* Next subreq->debug_index */
atomic_t nr_outstanding; /* Number of ops in progress */
atomic_t nr_copy_ops; /* Number of copy-to-cache ops in progress */
size_t submitted; /* Amount submitted for I/O so far */
size_t len; /* Length of the request */
+ size_t upper_len; /* Length can be extended to here */
+ size_t transferred; /* Amount to be indicated as transferred */
short error; /* 0 or error that occurred */
enum netfs_io_origin origin; /* Origin of the request */
bool direct_bv_unpin; /* T if direct_bv[] must be unpinned */
#define NETFS_RREQ_DONT_UNLOCK_FOLIOS 3 /* Don't unlock the folios on completion */
#define NETFS_RREQ_FAILED 4 /* The request failed */
#define NETFS_RREQ_IN_PROGRESS 5 /* Unlocked when the request completes */
+#define NETFS_RREQ_WRITE_TO_CACHE 7 /* Need to write to the cache */
+#define NETFS_RREQ_UPLOAD_TO_SERVER 8 /* Need to write to the server */
+#define NETFS_RREQ_NONBLOCK 9 /* Don't block if possible (O_NONBLOCK) */
+#define NETFS_RREQ_BLOCKED 10 /* We blocked */
const struct netfs_request_ops *netfs_ops;
+ void (*cleanup)(struct netfs_io_request *req);
};
/*
void (*free_request)(struct netfs_io_request *rreq);
void (*free_subrequest)(struct netfs_io_subrequest *rreq);
+ /* Read request handling */
void (*expand_readahead)(struct netfs_io_request *rreq);
bool (*clamp_length)(struct netfs_io_subrequest *subreq);
void (*issue_read)(struct netfs_io_subrequest *subreq);
int (*check_write_begin)(struct file *file, loff_t pos, unsigned len,
struct folio **foliop, void **_fsdata);
void (*done)(struct netfs_io_request *rreq);
+
+ /* Modification handling */
+ void (*update_i_size)(struct inode *inode, loff_t i_size);
+
+ /* Write request handling */
+ void (*create_write_requests)(struct netfs_io_request *wreq,
+ loff_t start, size_t len);
+ void (*invalidate_cache)(struct netfs_io_request *wreq);
};
/*
* actually do.
*/
int (*prepare_write)(struct netfs_cache_resources *cres,
- loff_t *_start, size_t *_len, loff_t i_size,
- bool no_space_allocated_yet);
+ loff_t *_start, size_t *_len, size_t upper_len,
+ loff_t i_size, bool no_space_allocated_yet);
/* Prepare an on-demand read operation, shortening it to a cached/uncached
* boundary as appropriate.
loff_t *_data_start, size_t *_data_len);
};
+/* High-level read API. */
+ssize_t netfs_unbuffered_read_iter(struct kiocb *iocb, struct iov_iter *iter);
+ssize_t netfs_buffered_read_iter(struct kiocb *iocb, struct iov_iter *iter);
+ssize_t netfs_file_read_iter(struct kiocb *iocb, struct iov_iter *iter);
+
+/* High-level write API */
+ssize_t netfs_perform_write(struct kiocb *iocb, struct iov_iter *iter,
+ struct netfs_group *netfs_group);
+ssize_t netfs_buffered_write_iter_locked(struct kiocb *iocb, struct iov_iter *from,
+ struct netfs_group *netfs_group);
+ssize_t netfs_unbuffered_write_iter(struct kiocb *iocb, struct iov_iter *from);
+ssize_t netfs_file_write_iter(struct kiocb *iocb, struct iov_iter *from);
+
+/* Address operations API */
struct readahead_control;
void netfs_readahead(struct readahead_control *);
int netfs_read_folio(struct file *, struct folio *);
int netfs_write_begin(struct netfs_inode *, struct file *,
struct address_space *, loff_t pos, unsigned int len,
struct folio **, void **fsdata);
+int netfs_writepages(struct address_space *mapping,
+ struct writeback_control *wbc);
bool netfs_dirty_folio(struct address_space *mapping, struct folio *folio);
int netfs_unpin_writeback(struct inode *inode, struct writeback_control *wbc);
void netfs_clear_inode_writeback(struct inode *inode, const void *aux);
void netfs_invalidate_folio(struct folio *folio, size_t offset, size_t length);
bool netfs_release_folio(struct folio *folio, gfp_t gfp);
+int netfs_launder_folio(struct folio *folio);
+
+/* VMA operations API. */
+vm_fault_t netfs_page_mkwrite(struct vm_fault *vmf, struct netfs_group *netfs_group);
+/* (Sub)request management API. */
void netfs_subreq_terminated(struct netfs_io_subrequest *, ssize_t, bool);
void netfs_get_subrequest(struct netfs_io_subrequest *subreq,
enum netfs_sreq_ref_trace what);
iov_iter_extraction_t extraction_flags);
size_t netfs_limit_iter(const struct iov_iter *iter, size_t start_offset,
size_t max_size, size_t max_segs);
+struct netfs_io_subrequest *netfs_create_write_request(
+ struct netfs_io_request *wreq, enum netfs_io_source dest,
+ loff_t start, size_t len, work_func_t worker);
+void netfs_write_subrequest_terminated(void *_op, ssize_t transferred_or_error,
+ bool was_async);
+void netfs_queue_write_request(struct netfs_io_subrequest *subreq);
int netfs_start_io_read(struct inode *inode);
void netfs_end_io_read(struct inode *inode);
* netfs_inode_init - Initialise a netfslib inode context
* @ctx: The netfs inode to initialise
* @ops: The netfs's operations list
+ * @use_zero_point: True to use the zero_point read optimisation
*
* Initialise the netfs library context struct. This is expected to follow on
* directly from the VFS inode struct.
*/
static inline void netfs_inode_init(struct netfs_inode *ctx,
- const struct netfs_request_ops *ops)
+ const struct netfs_request_ops *ops,
+ bool use_zero_point)
{
ctx->ops = ops;
ctx->remote_i_size = i_size_read(&ctx->inode);
+ ctx->zero_point = LLONG_MAX;
ctx->flags = 0;
#if IS_ENABLED(CONFIG_FSCACHE)
ctx->cache = NULL;
#endif
+ /* ->releasepage() drives zero_point */
+ if (use_zero_point) {
+ ctx->zero_point = ctx->remote_i_size;
+ mapping_set_release_always(ctx->inode.i_mapping);
+ }
}
/**
* netfs_resize_file - Note that a file got resized
* @ctx: The netfs inode being resized
* @new_i_size: The new file size
+ * @changed_on_server: The change was applied to the server
*
* Inform the netfs lib that a file got resized so that it can adjust its state.
*/
-static inline void netfs_resize_file(struct netfs_inode *ctx, loff_t new_i_size)
+static inline void netfs_resize_file(struct netfs_inode *ctx, loff_t new_i_size,
+ bool changed_on_server)
{
- ctx->remote_i_size = new_i_size;
+ if (changed_on_server)
+ ctx->remote_i_size = new_i_size;
+ if (new_i_size < ctx->zero_point)
+ ctx->zero_point = new_i_size;
}
/**
projects / linux-2.6-microblaze.git / blobdiff