vlclient.o \
vlocation.o \
vnode.o \
- volume.o
+ volume.o \
+ write.o
obj-$(CONFIG_AFS_FS) := kafs.o
enum AFS_FS_Operations {
FSFETCHDATA = 130, /* AFS Fetch file data */
FSFETCHSTATUS = 132, /* AFS Fetch file status */
+ FSSTOREDATA = 133, /* AFS Store file data */
+ FSSTORESTATUS = 135, /* AFS Store file status */
FSREMOVEFILE = 136, /* AFS Remove a file */
FSCREATEFILE = 137, /* AFS Create a file */
FSRENAME = 138, /* AFS Rename or move a file or directory */
.rename = afs_rename,
.permission = afs_permission,
.getattr = afs_getattr,
+ .setattr = afs_setattr,
};
static struct dentry_operations afs_fs_dentry_operations = {
#include <linux/slab.h>
#include <linux/fs.h>
#include <linux/pagemap.h>
+#include <linux/writeback.h>
#include "internal.h"
static int afs_readpage(struct file *file, struct page *page);
static void afs_invalidatepage(struct page *page, unsigned long offset);
static int afs_releasepage(struct page *page, gfp_t gfp_flags);
+static int afs_launder_page(struct page *page);
const struct file_operations afs_file_operations = {
.open = afs_open,
.release = afs_release,
.llseek = generic_file_llseek,
.read = do_sync_read,
+ .write = do_sync_write,
.aio_read = generic_file_aio_read,
+ .aio_write = afs_file_write,
.mmap = generic_file_readonly_mmap,
.sendfile = generic_file_sendfile,
+ .fsync = afs_fsync,
};
const struct inode_operations afs_file_inode_operations = {
.getattr = afs_getattr,
+ .setattr = afs_setattr,
.permission = afs_permission,
};
const struct address_space_operations afs_fs_aops = {
.readpage = afs_readpage,
- .set_page_dirty = __set_page_dirty_nobuffers,
+ .set_page_dirty = afs_set_page_dirty,
+ .launder_page = afs_launder_page,
.releasepage = afs_releasepage,
.invalidatepage = afs_invalidatepage,
+ .prepare_write = afs_prepare_write,
+ .commit_write = afs_commit_write,
+ .writepage = afs_writepage,
+ .writepages = afs_writepages,
};
/*
BUG_ON(!PageLocked(page));
if (PagePrivate(page)) {
-#ifdef AFS_CACHING_SUPPORT
- struct afs_vnode *vnode = AFS_FS_I(page->mapping->host);
- cachefs_uncache_page(vnode->cache,page);
-#endif
-
/* We release buffers only if the entire page is being
* invalidated.
* The get_block cached value has been unconditionally
_leave(" = %d", ret);
}
+/*
+ * write back a dirty page
+ */
+static int afs_launder_page(struct page *page)
+{
+ _enter("{%lu}", page->index);
+
+ return 0;
+}
+
/*
* release a page and cleanup its private data
*/
static int afs_releasepage(struct page *page, gfp_t gfp_flags)
{
struct afs_vnode *vnode = AFS_FS_I(page->mapping->host);
+ struct afs_writeback *wb;
_enter("{{%x:%u}[%lu],%lx},%x",
vnode->fid.vid, vnode->fid.vnode, page->index, page->flags,
gfp_flags);
if (PagePrivate(page)) {
+ wb = (struct afs_writeback *) page_private(page);
+ ASSERT(wb != NULL);
set_page_private(page, 0);
ClearPagePrivate(page);
+ afs_put_writeback(wb);
}
_leave(" = 0");
*/
static void xdr_decode_AFSFetchStatus(const __be32 **_bp,
struct afs_file_status *status,
- struct afs_vnode *vnode)
+ struct afs_vnode *vnode,
+ afs_dataversion_t *store_version)
{
+ afs_dataversion_t expected_version;
const __be32 *bp = *_bp;
umode_t mode;
u64 data_version, size;
vnode->vfs_inode.i_atime = vnode->vfs_inode.i_ctime;
}
- if (status->data_version != data_version) {
+ expected_version = status->data_version;
+ if (store_version)
+ expected_version = *store_version;
+
+ if (expected_version != data_version) {
status->data_version = data_version;
if (vnode && !test_bit(AFS_VNODE_UNSET, &vnode->flags)) {
_debug("vnode modified %llx on {%x:%u}",
set_bit(AFS_VNODE_MODIFIED, &vnode->flags);
set_bit(AFS_VNODE_ZAP_DATA, &vnode->flags);
}
+ } else if (store_version) {
+ status->data_version = data_version;
}
}
*_bp = bp;
}
+/*
+ * encode the requested attributes into an AFSStoreStatus block
+ */
+static void xdr_encode_AFS_StoreStatus(__be32 **_bp, struct iattr *attr)
+{
+ __be32 *bp = *_bp;
+ u32 mask = 0, mtime = 0, owner = 0, group = 0, mode = 0;
+
+ mask = 0;
+ if (attr->ia_valid & ATTR_MTIME) {
+ mask |= AFS_SET_MTIME;
+ mtime = attr->ia_mtime.tv_sec;
+ }
+
+ if (attr->ia_valid & ATTR_UID) {
+ mask |= AFS_SET_OWNER;
+ owner = attr->ia_uid;
+ }
+
+ if (attr->ia_valid & ATTR_GID) {
+ mask |= AFS_SET_GROUP;
+ group = attr->ia_gid;
+ }
+
+ if (attr->ia_valid & ATTR_MODE) {
+ mask |= AFS_SET_MODE;
+ mode = attr->ia_mode & S_IALLUGO;
+ }
+
+ *bp++ = htonl(mask);
+ *bp++ = htonl(mtime);
+ *bp++ = htonl(owner);
+ *bp++ = htonl(group);
+ *bp++ = htonl(mode);
+ *bp++ = 0; /* segment size */
+ *_bp = bp;
+}
+
/*
* deliver reply data to an FS.FetchStatus
*/
/* unmarshall the reply once we've received all of it */
bp = call->buffer;
- xdr_decode_AFSFetchStatus(&bp, &vnode->status, vnode);
+ xdr_decode_AFSFetchStatus(&bp, &vnode->status, vnode, NULL);
xdr_decode_AFSCallBack(&bp, vnode);
if (call->reply2)
xdr_decode_AFSVolSync(&bp, call->reply2);
}
bp = call->buffer;
- xdr_decode_AFSFetchStatus(&bp, &vnode->status, vnode);
+ xdr_decode_AFSFetchStatus(&bp, &vnode->status, vnode, NULL);
xdr_decode_AFSCallBack(&bp, vnode);
if (call->reply2)
xdr_decode_AFSVolSync(&bp, call->reply2);
/* unmarshall the reply once we've received all of it */
bp = call->buffer;
xdr_decode_AFSFid(&bp, call->reply2);
- xdr_decode_AFSFetchStatus(&bp, call->reply3, NULL);
- xdr_decode_AFSFetchStatus(&bp, &vnode->status, vnode);
+ xdr_decode_AFSFetchStatus(&bp, call->reply3, NULL, NULL);
+ xdr_decode_AFSFetchStatus(&bp, &vnode->status, vnode, NULL);
xdr_decode_AFSCallBack_raw(&bp, call->reply4);
/* xdr_decode_AFSVolSync(&bp, call->replyX); */
/* unmarshall the reply once we've received all of it */
bp = call->buffer;
- xdr_decode_AFSFetchStatus(&bp, &vnode->status, vnode);
+ xdr_decode_AFSFetchStatus(&bp, &vnode->status, vnode, NULL);
/* xdr_decode_AFSVolSync(&bp, call->replyX); */
_leave(" = 0 [done]");
/* unmarshall the reply once we've received all of it */
bp = call->buffer;
- xdr_decode_AFSFetchStatus(&bp, &vnode->status, vnode);
- xdr_decode_AFSFetchStatus(&bp, &dvnode->status, dvnode);
+ xdr_decode_AFSFetchStatus(&bp, &vnode->status, vnode, NULL);
+ xdr_decode_AFSFetchStatus(&bp, &dvnode->status, dvnode, NULL);
/* xdr_decode_AFSVolSync(&bp, call->replyX); */
_leave(" = 0 [done]");
/* unmarshall the reply once we've received all of it */
bp = call->buffer;
xdr_decode_AFSFid(&bp, call->reply2);
- xdr_decode_AFSFetchStatus(&bp, call->reply3, NULL);
- xdr_decode_AFSFetchStatus(&bp, &vnode->status, vnode);
+ xdr_decode_AFSFetchStatus(&bp, call->reply3, NULL, NULL);
+ xdr_decode_AFSFetchStatus(&bp, &vnode->status, vnode, NULL);
/* xdr_decode_AFSVolSync(&bp, call->replyX); */
_leave(" = 0 [done]");
/* unmarshall the reply once we've received all of it */
bp = call->buffer;
- xdr_decode_AFSFetchStatus(&bp, &orig_dvnode->status, orig_dvnode);
+ xdr_decode_AFSFetchStatus(&bp, &orig_dvnode->status, orig_dvnode, NULL);
if (new_dvnode != orig_dvnode)
- xdr_decode_AFSFetchStatus(&bp, &new_dvnode->status, new_dvnode);
+ xdr_decode_AFSFetchStatus(&bp, &new_dvnode->status, new_dvnode,
+ NULL);
/* xdr_decode_AFSVolSync(&bp, call->replyX); */
_leave(" = 0 [done]");
return afs_make_call(&server->addr, call, GFP_NOFS, wait_mode);
}
+
+/*
+ * deliver reply data to an FS.StoreData
+ */
+static int afs_deliver_fs_store_data(struct afs_call *call,
+ struct sk_buff *skb, bool last)
+{
+ struct afs_vnode *vnode = call->reply;
+ const __be32 *bp;
+
+ _enter(",,%u", last);
+
+ afs_transfer_reply(call, skb);
+ if (!last) {
+ _leave(" = 0 [more]");
+ return 0;
+ }
+
+ if (call->reply_size != call->reply_max) {
+ _leave(" = -EBADMSG [%u != %u]",
+ call->reply_size, call->reply_max);
+ return -EBADMSG;
+ }
+
+ /* unmarshall the reply once we've received all of it */
+ bp = call->buffer;
+ xdr_decode_AFSFetchStatus(&bp, &vnode->status, vnode,
+ &call->store_version);
+ /* xdr_decode_AFSVolSync(&bp, call->replyX); */
+
+ afs_pages_written_back(vnode, call);
+
+ _leave(" = 0 [done]");
+ return 0;
+}
+
+/*
+ * FS.StoreData operation type
+ */
+static const struct afs_call_type afs_RXFSStoreData = {
+ .name = "FS.StoreData",
+ .deliver = afs_deliver_fs_store_data,
+ .abort_to_error = afs_abort_to_error,
+ .destructor = afs_flat_call_destructor,
+};
+
+/*
+ * store a set of pages
+ */
+int afs_fs_store_data(struct afs_server *server, struct afs_writeback *wb,
+ pgoff_t first, pgoff_t last,
+ unsigned offset, unsigned to,
+ const struct afs_wait_mode *wait_mode)
+{
+ struct afs_vnode *vnode = wb->vnode;
+ struct afs_call *call;
+ loff_t size, pos, i_size;
+ __be32 *bp;
+
+ _enter(",%x,{%x:%u},,",
+ key_serial(wb->key), vnode->fid.vid, vnode->fid.vnode);
+
+ size = to - offset;
+ if (first != last)
+ size += (loff_t)(last - first) << PAGE_SHIFT;
+ pos = (loff_t)first << PAGE_SHIFT;
+ pos += offset;
+
+ i_size = i_size_read(&vnode->vfs_inode);
+ if (pos + size > i_size)
+ i_size = size + pos;
+
+ _debug("size %llx, at %llx, i_size %llx",
+ (unsigned long long) size, (unsigned long long) pos,
+ (unsigned long long) i_size);
+
+ BUG_ON(i_size > 0xffffffff); // TODO: use 64-bit store
+
+ call = afs_alloc_flat_call(&afs_RXFSStoreData,
+ (4 + 6 + 3) * 4,
+ (21 + 6) * 4);
+ if (!call)
+ return -ENOMEM;
+
+ call->wb = wb;
+ call->key = wb->key;
+ call->reply = vnode;
+ call->service_id = FS_SERVICE;
+ call->port = htons(AFS_FS_PORT);
+ call->mapping = vnode->vfs_inode.i_mapping;
+ call->first = first;
+ call->last = last;
+ call->first_offset = offset;
+ call->last_to = to;
+ call->send_pages = true;
+ call->store_version = vnode->status.data_version + 1;
+
+ /* marshall the parameters */
+ bp = call->request;
+ *bp++ = htonl(FSSTOREDATA);
+ *bp++ = htonl(vnode->fid.vid);
+ *bp++ = htonl(vnode->fid.vnode);
+ *bp++ = htonl(vnode->fid.unique);
+
+ *bp++ = 0; /* mask */
+ *bp++ = 0; /* mtime */
+ *bp++ = 0; /* owner */
+ *bp++ = 0; /* group */
+ *bp++ = 0; /* unix mode */
+ *bp++ = 0; /* segment size */
+
+ *bp++ = htonl(pos);
+ *bp++ = htonl(size);
+ *bp++ = htonl(i_size);
+
+ return afs_make_call(&server->addr, call, GFP_NOFS, wait_mode);
+}
+
+/*
+ * deliver reply data to an FS.StoreStatus
+ */
+static int afs_deliver_fs_store_status(struct afs_call *call,
+ struct sk_buff *skb, bool last)
+{
+ afs_dataversion_t *store_version;
+ struct afs_vnode *vnode = call->reply;
+ const __be32 *bp;
+
+ _enter(",,%u", last);
+
+ afs_transfer_reply(call, skb);
+ if (!last) {
+ _leave(" = 0 [more]");
+ return 0;
+ }
+
+ if (call->reply_size != call->reply_max) {
+ _leave(" = -EBADMSG [%u != %u]",
+ call->reply_size, call->reply_max);
+ return -EBADMSG;
+ }
+
+ /* unmarshall the reply once we've received all of it */
+ store_version = NULL;
+ if (call->operation_ID == FSSTOREDATA)
+ store_version = &call->store_version;
+
+ bp = call->buffer;
+ xdr_decode_AFSFetchStatus(&bp, &vnode->status, vnode, store_version);
+ /* xdr_decode_AFSVolSync(&bp, call->replyX); */
+
+ _leave(" = 0 [done]");
+ return 0;
+}
+
+/*
+ * FS.StoreStatus operation type
+ */
+static const struct afs_call_type afs_RXFSStoreStatus = {
+ .name = "FS.StoreStatus",
+ .deliver = afs_deliver_fs_store_status,
+ .abort_to_error = afs_abort_to_error,
+ .destructor = afs_flat_call_destructor,
+};
+
+static const struct afs_call_type afs_RXFSStoreData_as_Status = {
+ .name = "FS.StoreData",
+ .deliver = afs_deliver_fs_store_status,
+ .abort_to_error = afs_abort_to_error,
+ .destructor = afs_flat_call_destructor,
+};
+
+/*
+ * set the attributes on a file, using FS.StoreData rather than FS.StoreStatus
+ * so as to alter the file size also
+ */
+static int afs_fs_setattr_size(struct afs_server *server, struct key *key,
+ struct afs_vnode *vnode, struct iattr *attr,
+ const struct afs_wait_mode *wait_mode)
+{
+ struct afs_call *call;
+ __be32 *bp;
+
+ _enter(",%x,{%x:%u},,",
+ key_serial(key), vnode->fid.vid, vnode->fid.vnode);
+
+ ASSERT(attr->ia_valid & ATTR_SIZE);
+ ASSERTCMP(attr->ia_size, <=, 0xffffffff); // TODO: use 64-bit store
+
+ call = afs_alloc_flat_call(&afs_RXFSStoreData_as_Status,
+ (4 + 6 + 3) * 4,
+ (21 + 6) * 4);
+ if (!call)
+ return -ENOMEM;
+
+ call->key = key;
+ call->reply = vnode;
+ call->service_id = FS_SERVICE;
+ call->port = htons(AFS_FS_PORT);
+ call->store_version = vnode->status.data_version + 1;
+ call->operation_ID = FSSTOREDATA;
+
+ /* marshall the parameters */
+ bp = call->request;
+ *bp++ = htonl(FSSTOREDATA);
+ *bp++ = htonl(vnode->fid.vid);
+ *bp++ = htonl(vnode->fid.vnode);
+ *bp++ = htonl(vnode->fid.unique);
+
+ xdr_encode_AFS_StoreStatus(&bp, attr);
+
+ *bp++ = 0; /* position of start of write */
+ *bp++ = 0; /* size of write */
+ *bp++ = htonl(attr->ia_size); /* new file length */
+
+ return afs_make_call(&server->addr, call, GFP_NOFS, wait_mode);
+}
+
+/*
+ * set the attributes on a file, using FS.StoreData if there's a change in file
+ * size, and FS.StoreStatus otherwise
+ */
+int afs_fs_setattr(struct afs_server *server, struct key *key,
+ struct afs_vnode *vnode, struct iattr *attr,
+ const struct afs_wait_mode *wait_mode)
+{
+ struct afs_call *call;
+ __be32 *bp;
+
+ if (attr->ia_valid & ATTR_SIZE)
+ return afs_fs_setattr_size(server, key, vnode, attr,
+ wait_mode);
+
+ _enter(",%x,{%x:%u},,",
+ key_serial(key), vnode->fid.vid, vnode->fid.vnode);
+
+ call = afs_alloc_flat_call(&afs_RXFSStoreStatus,
+ (4 + 6) * 4,
+ (21 + 6) * 4);
+ if (!call)
+ return -ENOMEM;
+
+ call->key = key;
+ call->reply = vnode;
+ call->service_id = FS_SERVICE;
+ call->port = htons(AFS_FS_PORT);
+ call->operation_ID = FSSTORESTATUS;
+
+ /* marshall the parameters */
+ bp = call->request;
+ *bp++ = htonl(FSSTORESTATUS);
+ *bp++ = htonl(vnode->fid.vid);
+ *bp++ = htonl(vnode->fid.vnode);
+ *bp++ = htonl(vnode->fid.unique);
+
+ xdr_encode_AFS_StoreStatus(&bp, attr);
+
+ return afs_make_call(&server->addr, call, GFP_NOFS, wait_mode);
+}
*/
void afs_zap_data(struct afs_vnode *vnode)
{
- kenter("zap data {%x:%u}", vnode->fid.vid, vnode->fid.vnode);
+ _enter("zap data {%x:%u}", vnode->fid.vid, vnode->fid.vnode);
/* nuke all the non-dirty pages that aren't locked, mapped or being
* written back */
vnode->server = NULL;
}
+ ASSERT(list_empty(&vnode->writebacks));
ASSERT(!vnode->cb_promised);
#ifdef AFS_CACHING_SUPPORT
_leave("");
}
+
+/*
+ * set the attributes of an inode
+ */
+int afs_setattr(struct dentry *dentry, struct iattr *attr)
+{
+ struct afs_vnode *vnode = AFS_FS_I(dentry->d_inode);
+ struct key *key;
+ int ret;
+
+ _enter("{%x:%u},{n=%s},%x",
+ vnode->fid.vid, vnode->fid.vnode, dentry->d_name.name,
+ attr->ia_valid);
+
+ if (!(attr->ia_valid & (ATTR_SIZE | ATTR_MODE | ATTR_UID | ATTR_GID |
+ ATTR_MTIME))) {
+ _leave(" = 0 [unsupported]");
+ return 0;
+ }
+
+ /* flush any dirty data outstanding on a regular file */
+ if (S_ISREG(vnode->vfs_inode.i_mode)) {
+ filemap_write_and_wait(vnode->vfs_inode.i_mapping);
+ afs_writeback_all(vnode);
+ }
+
+ if (attr->ia_valid & ATTR_FILE) {
+ key = attr->ia_file->private_data;
+ } else {
+ key = afs_request_key(vnode->volume->cell);
+ if (IS_ERR(key)) {
+ ret = PTR_ERR(key);
+ goto error;
+ }
+ }
+
+ ret = afs_vnode_setattr(vnode, key, attr);
+ if (!(attr->ia_valid & ATTR_FILE))
+ key_put(key);
+
+error:
+ _leave(" = %d", ret);
+ return ret;
+}
#define AFS_CELL_MAX_ADDRS 15
+struct pagevec;
struct afs_call;
typedef enum {
struct key *key; /* security for this call */
struct afs_server *server; /* server affected by incoming CM call */
void *request; /* request data (first part) */
- void *request2; /* request data (second part) */
+ struct address_space *mapping; /* page set */
+ struct afs_writeback *wb; /* writeback being performed */
void *buffer; /* reply receive buffer */
void *reply; /* reply buffer (first part) */
void *reply2; /* reply buffer (second part) */
void *reply3; /* reply buffer (third part) */
void *reply4; /* reply buffer (fourth part) */
+ pgoff_t first; /* first page in mapping to deal with */
+ pgoff_t last; /* last page in mapping to deal with */
enum { /* call state */
AFS_CALL_REQUESTING, /* request is being sent for outgoing call */
AFS_CALL_AWAIT_REPLY, /* awaiting reply to outgoing call */
unsigned request_size; /* size of request data */
unsigned reply_max; /* maximum size of reply */
unsigned reply_size; /* current size of reply */
+ unsigned first_offset; /* offset into mapping[first] */
+ unsigned last_to; /* amount of mapping[last] */
unsigned short offset; /* offset into received data store */
unsigned char unmarshall; /* unmarshalling phase */
bool incoming; /* T if incoming call */
+ bool send_pages; /* T if data from mapping should be sent */
u16 service_id; /* RxRPC service ID to call */
__be16 port; /* target UDP port */
__be32 operation_ID; /* operation ID for an incoming call */
u32 count; /* count for use in unmarshalling */
__be32 tmp; /* place to extract temporary data */
+ afs_dataversion_t store_version; /* updated version expected from store */
};
struct afs_call_type {
void (*destructor)(struct afs_call *call);
};
+/*
+ * record of an outstanding writeback on a vnode
+ */
+struct afs_writeback {
+ struct list_head link; /* link in vnode->writebacks */
+ struct work_struct writer; /* work item to perform the writeback */
+ struct afs_vnode *vnode; /* vnode to which this write applies */
+ struct key *key; /* owner of this write */
+ wait_queue_head_t waitq; /* completion and ready wait queue */
+ pgoff_t first; /* first page in batch */
+ pgoff_t point; /* last page in current store op */
+ pgoff_t last; /* last page in batch (inclusive) */
+ unsigned offset_first; /* offset into first page of start of write */
+ unsigned to_last; /* offset into last page of end of write */
+ int num_conflicts; /* count of conflicting writes in list */
+ int usage;
+ bool conflicts; /* T if has dependent conflicts */
+ enum {
+ AFS_WBACK_SYNCING, /* synchronisation being performed */
+ AFS_WBACK_PENDING, /* write pending */
+ AFS_WBACK_CONFLICTING, /* conflicting writes posted */
+ AFS_WBACK_WRITING, /* writing back */
+ AFS_WBACK_COMPLETE /* the writeback record has been unlinked */
+ } state __attribute__((packed));
+};
+
/*
* AFS superblock private data
* - there's one superblock per volume
wait_queue_head_t update_waitq; /* status fetch waitqueue */
int update_cnt; /* number of outstanding ops that will update the
* status */
+ spinlock_t writeback_lock; /* lock for writebacks */
spinlock_t lock; /* waitqueue/flags lock */
unsigned long flags;
#define AFS_VNODE_CB_BROKEN 0 /* set if vnode's callback was broken */
long acl_order; /* ACL check count (callback break count) */
+ struct list_head writebacks; /* alterations in pagecache that need writing */
+
/* outstanding callback notification on this file */
struct rb_node server_rb; /* link in server->fs_vnodes */
struct rb_node cb_promise; /* link in server->cb_promises */
struct afs_vnode *, const char *,
struct afs_vnode *, const char *,
const struct afs_wait_mode *);
+extern int afs_fs_store_data(struct afs_server *, struct afs_writeback *,
+ pgoff_t, pgoff_t, unsigned, unsigned,
+ const struct afs_wait_mode *);
+extern int afs_fs_setattr(struct afs_server *, struct key *,
+ struct afs_vnode *, struct iattr *,
+ const struct afs_wait_mode *);
/*
* inode.c
extern void afs_zap_data(struct afs_vnode *);
extern int afs_validate(struct afs_vnode *, struct key *);
extern int afs_getattr(struct vfsmount *, struct dentry *, struct kstat *);
+extern int afs_setattr(struct dentry *, struct iattr *);
extern void afs_clear_inode(struct inode *);
/*
struct afs_file_status *, struct afs_server **);
extern int afs_vnode_rename(struct afs_vnode *, struct afs_vnode *,
struct key *, const char *, const char *);
+extern int afs_vnode_store_data(struct afs_writeback *, pgoff_t, pgoff_t,
+ unsigned, unsigned);
+extern int afs_vnode_setattr(struct afs_vnode *, struct key *, struct iattr *);
/*
* volume.c
extern int afs_volume_release_fileserver(struct afs_vnode *,
struct afs_server *, int);
+/*
+ * write.c
+ */
+extern int afs_set_page_dirty(struct page *);
+extern void afs_put_writeback(struct afs_writeback *);
+extern int afs_prepare_write(struct file *, struct page *, unsigned, unsigned);
+extern int afs_commit_write(struct file *, struct page *, unsigned, unsigned);
+extern int afs_writepage(struct page *, struct writeback_control *);
+extern int afs_writepages(struct address_space *, struct writeback_control *);
+extern int afs_write_inode(struct inode *, int);
+extern void afs_pages_written_back(struct afs_vnode *, struct afs_call *);
+extern ssize_t afs_file_write(struct kiocb *, const struct iovec *,
+ unsigned long, loff_t);
+extern int afs_writeback_all(struct afs_vnode *);
+extern int afs_fsync(struct file *, struct dentry *, int);
+
+
/*****************************************************************************/
/*
* debug tracing
call->buffer = NULL;
}
+/*
+ * attach the data from a bunch of pages on an inode to a call
+ */
+int afs_send_pages(struct afs_call *call, struct msghdr *msg, struct kvec *iov)
+{
+ struct page *pages[8];
+ unsigned count, n, loop, offset, to;
+ pgoff_t first = call->first, last = call->last;
+ int ret;
+
+ _enter("");
+
+ offset = call->first_offset;
+ call->first_offset = 0;
+
+ do {
+ _debug("attach %lx-%lx", first, last);
+
+ count = last - first + 1;
+ if (count > ARRAY_SIZE(pages))
+ count = ARRAY_SIZE(pages);
+ n = find_get_pages_contig(call->mapping, first, count, pages);
+ ASSERTCMP(n, ==, count);
+
+ loop = 0;
+ do {
+ msg->msg_flags = 0;
+ to = PAGE_SIZE;
+ if (first + loop >= last)
+ to = call->last_to;
+ else
+ msg->msg_flags = MSG_MORE;
+ iov->iov_base = kmap(pages[loop]) + offset;
+ iov->iov_len = to - offset;
+ offset = 0;
+
+ _debug("- range %u-%u%s",
+ offset, to, msg->msg_flags ? " [more]" : "");
+ msg->msg_iov = (struct iovec *) iov;
+ msg->msg_iovlen = 1;
+
+ /* have to change the state *before* sending the last
+ * packet as RxRPC might give us the reply before it
+ * returns from sending the request */
+ if (first + loop >= last)
+ call->state = AFS_CALL_AWAIT_REPLY;
+ ret = rxrpc_kernel_send_data(call->rxcall, msg,
+ to - offset);
+ kunmap(pages[loop]);
+ if (ret < 0)
+ break;
+ } while (++loop < count);
+ first += count;
+
+ for (loop = 0; loop < count; loop++)
+ put_page(pages[loop]);
+ if (ret < 0)
+ break;
+ } while (first < last);
+
+ _leave(" = %d", ret);
+ return ret;
+}
+
/*
* initiate a call
*/
ASSERT(call->type != NULL);
ASSERT(call->type->name != NULL);
- _debug("MAKE %p{%s} [%d]",
- call, call->type->name, atomic_read(&afs_outstanding_calls));
+ _debug("____MAKE %p{%s,%x} [%d]____",
+ call, call->type->name, key_serial(call->key),
+ atomic_read(&afs_outstanding_calls));
call->wait_mode = wait_mode;
INIT_WORK(&call->async_work, afs_process_async_call);
msg.msg_iovlen = 1;
msg.msg_control = NULL;
msg.msg_controllen = 0;
- msg.msg_flags = 0;
+ msg.msg_flags = (call->send_pages ? MSG_MORE : 0);
/* have to change the state *before* sending the last packet as RxRPC
* might give us the reply before it returns from sending the
* request */
- call->state = AFS_CALL_AWAIT_REPLY;
+ if (!call->send_pages)
+ call->state = AFS_CALL_AWAIT_REPLY;
ret = rxrpc_kernel_send_data(rxcall, &msg, call->request_size);
if (ret < 0)
goto error_do_abort;
+ if (call->send_pages) {
+ ret = afs_send_pages(call, &msg, iov);
+ if (ret < 0)
+ goto error_do_abort;
+ }
+
/* at this point, an async call may no longer exist as it may have
* already completed */
return wait_mode->wait(call);
.statfs = simple_statfs,
.alloc_inode = afs_alloc_inode,
.drop_inode = generic_delete_inode,
+ .write_inode = afs_write_inode,
.destroy_inode = afs_destroy_inode,
.clear_inode = afs_clear_inode,
.umount_begin = afs_umount_begin,
afs_opt_vol,
};
-static const match_table_t afs_options_list = {
+static match_table_t afs_options_list = {
{ afs_opt_cell, "cell=%s" },
{ afs_opt_rwpath, "rwpath" },
{ afs_opt_vol, "vol=%s" },
init_waitqueue_head(&vnode->update_waitq);
mutex_init(&vnode->permits_lock);
mutex_init(&vnode->validate_lock);
+ spin_lock_init(&vnode->writeback_lock);
spin_lock_init(&vnode->lock);
+ INIT_LIST_HEAD(&vnode->writebacks);
INIT_WORK(&vnode->cb_broken_work, afs_broken_callback_work);
}
}
_leave(" = %ld [cnt %d]", PTR_ERR(server), orig_dvnode->update_cnt);
return PTR_ERR(server);
}
+
+/*
+ * write to a file
+ */
+int afs_vnode_store_data(struct afs_writeback *wb, pgoff_t first, pgoff_t last,
+ unsigned offset, unsigned to)
+{
+ struct afs_server *server;
+ struct afs_vnode *vnode = wb->vnode;
+ int ret;
+
+ _enter("%s{%x:%u.%u},%x,%lx,%lx,%x,%x",
+ vnode->volume->vlocation->vldb.name,
+ vnode->fid.vid,
+ vnode->fid.vnode,
+ vnode->fid.unique,
+ key_serial(wb->key),
+ first, last, offset, to);
+
+ /* this op will fetch the status */
+ spin_lock(&vnode->lock);
+ vnode->update_cnt++;
+ spin_unlock(&vnode->lock);
+
+ do {
+ /* pick a server to query */
+ server = afs_volume_pick_fileserver(vnode);
+ if (IS_ERR(server))
+ goto no_server;
+
+ _debug("USING SERVER: %08x\n", ntohl(server->addr.s_addr));
+
+ ret = afs_fs_store_data(server, wb, first, last, offset, to,
+ &afs_sync_call);
+
+ } while (!afs_volume_release_fileserver(vnode, server, ret));
+
+ /* adjust the flags */
+ if (ret == 0) {
+ afs_vnode_finalise_status_update(vnode, server);
+ afs_put_server(server);
+ } else {
+ afs_vnode_status_update_failed(vnode, ret);
+ }
+
+ _leave(" = %d", ret);
+ return ret;
+
+no_server:
+ spin_lock(&vnode->lock);
+ vnode->update_cnt--;
+ ASSERTCMP(vnode->update_cnt, >=, 0);
+ spin_unlock(&vnode->lock);
+ return PTR_ERR(server);
+}
+
+/*
+ * set the attributes on a file
+ */
+int afs_vnode_setattr(struct afs_vnode *vnode, struct key *key,
+ struct iattr *attr)
+{
+ struct afs_server *server;
+ int ret;
+
+ _enter("%s{%x:%u.%u},%x",
+ vnode->volume->vlocation->vldb.name,
+ vnode->fid.vid,
+ vnode->fid.vnode,
+ vnode->fid.unique,
+ key_serial(key));
+
+ /* this op will fetch the status */
+ spin_lock(&vnode->lock);
+ vnode->update_cnt++;
+ spin_unlock(&vnode->lock);
+
+ do {
+ /* pick a server to query */
+ server = afs_volume_pick_fileserver(vnode);
+ if (IS_ERR(server))
+ goto no_server;
+
+ _debug("USING SERVER: %08x\n", ntohl(server->addr.s_addr));
+
+ ret = afs_fs_setattr(server, key, vnode, attr, &afs_sync_call);
+
+ } while (!afs_volume_release_fileserver(vnode, server, ret));
+
+ /* adjust the flags */
+ if (ret == 0) {
+ afs_vnode_finalise_status_update(vnode, server);
+ afs_put_server(server);
+ } else {
+ afs_vnode_status_update_failed(vnode, ret);
+ }
+
+ _leave(" = %d", ret);
+ return ret;
+
+no_server:
+ spin_lock(&vnode->lock);
+ vnode->update_cnt--;
+ ASSERTCMP(vnode->update_cnt, >=, 0);
+ spin_unlock(&vnode->lock);
+ return PTR_ERR(server);
+}
--- /dev/null
+/* handling of writes to regular files and writing back to the server
+ *
+ * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/slab.h>
+#include <linux/fs.h>
+#include <linux/pagemap.h>
+#include <linux/writeback.h>
+#include <linux/pagevec.h>
+#include "internal.h"
+
+static int afs_write_back_from_locked_page(struct afs_writeback *wb,
+ struct page *page);
+
+/*
+ * mark a page as having been made dirty and thus needing writeback
+ */
+int afs_set_page_dirty(struct page *page)
+{
+ _enter("");
+ return __set_page_dirty_nobuffers(page);
+}
+
+/*
+ * unlink a writeback record because its usage has reached zero
+ * - must be called with the wb->vnode->writeback_lock held
+ */
+static void afs_unlink_writeback(struct afs_writeback *wb)
+{
+ struct afs_writeback *front;
+ struct afs_vnode *vnode = wb->vnode;
+
+ list_del_init(&wb->link);
+ if (!list_empty(&vnode->writebacks)) {
+ /* if an fsync rises to the front of the queue then wake it
+ * up */
+ front = list_entry(vnode->writebacks.next,
+ struct afs_writeback, link);
+ if (front->state == AFS_WBACK_SYNCING) {
+ _debug("wake up sync");
+ front->state = AFS_WBACK_COMPLETE;
+ wake_up(&front->waitq);
+ }
+ }
+}
+
+/*
+ * free a writeback record
+ */
+static void afs_free_writeback(struct afs_writeback *wb)
+{
+ _enter("");
+ key_put(wb->key);
+ kfree(wb);
+}
+
+/*
+ * dispose of a reference to a writeback record
+ */
+void afs_put_writeback(struct afs_writeback *wb)
+{
+ struct afs_vnode *vnode = wb->vnode;
+
+ _enter("{%d}", wb->usage);
+
+ spin_lock(&vnode->writeback_lock);
+ if (--wb->usage == 0)
+ afs_unlink_writeback(wb);
+ else
+ wb = NULL;
+ spin_unlock(&vnode->writeback_lock);
+ if (wb)
+ afs_free_writeback(wb);
+}
+
+/*
+ * partly or wholly fill a page that's under preparation for writing
+ */
+static int afs_fill_page(struct afs_vnode *vnode, struct key *key,
+ unsigned start, unsigned len, struct page *page)
+{
+ int ret;
+
+ _enter(",,%u,%u", start, len);
+
+ ASSERTCMP(start + len, <=, PAGE_SIZE);
+
+ ret = afs_vnode_fetch_data(vnode, key, start, len, page);
+ if (ret < 0) {
+ if (ret == -ENOENT) {
+ _debug("got NOENT from server"
+ " - marking file deleted and stale");
+ set_bit(AFS_VNODE_DELETED, &vnode->flags);
+ ret = -ESTALE;
+ }
+ }
+
+ _leave(" = %d", ret);
+ return ret;
+}
+
+/*
+ * prepare a page for being written to
+ */
+static int afs_prepare_page(struct afs_vnode *vnode, struct page *page,
+ struct key *key, unsigned offset, unsigned to)
+{
+ unsigned eof, tail, start, stop, len;
+ loff_t i_size, pos;
+ void *p;
+ int ret;
+
+ _enter("");
+
+ if (offset == 0 && to == PAGE_SIZE)
+ return 0;
+
+ p = kmap(page);
+
+ i_size = i_size_read(&vnode->vfs_inode);
+ pos = (loff_t) page->index << PAGE_SHIFT;
+ if (pos >= i_size) {
+ /* partial write, page beyond EOF */
+ _debug("beyond");
+ if (offset > 0)
+ memset(p, 0, offset);
+ if (to < PAGE_SIZE)
+ memset(p + to, 0, PAGE_SIZE - to);
+ kunmap(page);
+ return 0;
+ }
+
+ if (i_size - pos >= PAGE_SIZE) {
+ /* partial write, page entirely before EOF */
+ _debug("before");
+ tail = eof = PAGE_SIZE;
+ } else {
+ /* partial write, page overlaps EOF */
+ eof = i_size - pos;
+ _debug("overlap %u", eof);
+ tail = max(eof, to);
+ if (tail < PAGE_SIZE)
+ memset(p + tail, 0, PAGE_SIZE - tail);
+ if (offset > eof)
+ memset(p + eof, 0, PAGE_SIZE - eof);
+ }
+
+ kunmap(p);
+
+ ret = 0;
+ if (offset > 0 || eof > to) {
+ /* need to fill one or two bits that aren't going to be written
+ * (cover both fillers in one read if there are two) */
+ start = (offset > 0) ? 0 : to;
+ stop = (eof > to) ? eof : offset;
+ len = stop - start;
+ _debug("wr=%u-%u av=0-%u rd=%u@%u",
+ offset, to, eof, start, len);
+ ret = afs_fill_page(vnode, key, start, len, page);
+ }
+
+ _leave(" = %d", ret);
+ return ret;
+}
+
+/*
+ * prepare to perform part of a write to a page
+ * - the caller holds the page locked, preventing it from being written out or
+ * modified by anyone else
+ */
+int afs_prepare_write(struct file *file, struct page *page,
+ unsigned offset, unsigned to)
+{
+ struct afs_writeback *candidate, *wb;
+ struct afs_vnode *vnode = AFS_FS_I(file->f_dentry->d_inode);
+ struct key *key = file->private_data;
+ pgoff_t index;
+ int ret;
+
+ _enter("{%x:%u},{%lx},%u,%u",
+ vnode->fid.vid, vnode->fid.vnode, page->index, offset, to);
+
+ candidate = kzalloc(sizeof(*candidate), GFP_KERNEL);
+ if (!candidate)
+ return -ENOMEM;
+ candidate->vnode = vnode;
+ candidate->first = candidate->last = page->index;
+ candidate->offset_first = offset;
+ candidate->to_last = to;
+ candidate->usage = 1;
+ candidate->state = AFS_WBACK_PENDING;
+ init_waitqueue_head(&candidate->waitq);
+
+ if (!PageUptodate(page)) {
+ _debug("not up to date");
+ ret = afs_prepare_page(vnode, page, key, offset, to);
+ if (ret < 0) {
+ kfree(candidate);
+ _leave(" = %d [prep]", ret);
+ return ret;
+ }
+ SetPageUptodate(page);
+ }
+
+try_again:
+ index = page->index;
+ spin_lock(&vnode->writeback_lock);
+
+ /* see if this page is already pending a writeback under a suitable key
+ * - if so we can just join onto that one */
+ wb = (struct afs_writeback *) page_private(page);
+ if (wb) {
+ if (wb->key == key && wb->state == AFS_WBACK_PENDING)
+ goto subsume_in_current_wb;
+ goto flush_conflicting_wb;
+ }
+
+ if (index > 0) {
+ /* see if we can find an already pending writeback that we can
+ * append this page to */
+ list_for_each_entry(wb, &vnode->writebacks, link) {
+ if (wb->last == index - 1 && wb->key == key &&
+ wb->state == AFS_WBACK_PENDING)
+ goto append_to_previous_wb;
+ }
+ }
+
+ list_add_tail(&candidate->link, &vnode->writebacks);
+ candidate->key = key_get(key);
+ spin_unlock(&vnode->writeback_lock);
+ SetPagePrivate(page);
+ set_page_private(page, (unsigned long) candidate);
+ _leave(" = 0 [new]");
+ return 0;
+
+subsume_in_current_wb:
+ _debug("subsume");
+ ASSERTRANGE(wb->first, <=, index, <=, wb->last);
+ if (index == wb->first && offset < wb->offset_first)
+ wb->offset_first = offset;
+ if (index == wb->last && to > wb->to_last)
+ wb->to_last = to;
+ spin_unlock(&vnode->writeback_lock);
+ kfree(candidate);
+ _leave(" = 0 [sub]");
+ return 0;
+
+append_to_previous_wb:
+ _debug("append into %lx-%lx", wb->first, wb->last);
+ wb->usage++;
+ wb->last++;
+ wb->to_last = to;
+ spin_unlock(&vnode->writeback_lock);
+ SetPagePrivate(page);
+ set_page_private(page, (unsigned long) wb);
+ kfree(candidate);
+ _leave(" = 0 [app]");
+ return 0;
+
+ /* the page is currently bound to another context, so if it's dirty we
+ * need to flush it before we can use the new context */
+flush_conflicting_wb:
+ _debug("flush conflict");
+ if (wb->state == AFS_WBACK_PENDING)
+ wb->state = AFS_WBACK_CONFLICTING;
+ spin_unlock(&vnode->writeback_lock);
+ if (PageDirty(page)) {
+ ret = afs_write_back_from_locked_page(wb, page);
+ if (ret < 0) {
+ afs_put_writeback(candidate);
+ _leave(" = %d", ret);
+ return ret;
+ }
+ }
+
+ /* the page holds a ref on the writeback record */
+ afs_put_writeback(wb);
+ set_page_private(page, 0);
+ ClearPagePrivate(page);
+ goto try_again;
+}
+
+/*
+ * finalise part of a write to a page
+ */
+int afs_commit_write(struct file *file, struct page *page,
+ unsigned offset, unsigned to)
+{
+ struct afs_vnode *vnode = AFS_FS_I(file->f_dentry->d_inode);
+ loff_t i_size, maybe_i_size;
+
+ _enter("{%x:%u},{%lx},%u,%u",
+ vnode->fid.vid, vnode->fid.vnode, page->index, offset, to);
+
+ maybe_i_size = (loff_t) page->index << PAGE_SHIFT;
+ maybe_i_size += to;
+
+ i_size = i_size_read(&vnode->vfs_inode);
+ if (maybe_i_size > i_size) {
+ spin_lock(&vnode->writeback_lock);
+ i_size = i_size_read(&vnode->vfs_inode);
+ if (maybe_i_size > i_size)
+ i_size_write(&vnode->vfs_inode, maybe_i_size);
+ spin_unlock(&vnode->writeback_lock);
+ }
+
+ set_page_dirty(page);
+
+ if (PageDirty(page))
+ _debug("dirtied");
+
+ return 0;
+}
+
+/*
+ * kill all the pages in the given range
+ */
+static void afs_kill_pages(struct afs_vnode *vnode, bool error,
+ pgoff_t first, pgoff_t last)
+{
+ struct pagevec pv;
+ unsigned count, loop;
+
+ _enter("{%x:%u},%lx-%lx",
+ vnode->fid.vid, vnode->fid.vnode, first, last);
+
+ pagevec_init(&pv, 0);
+
+ do {
+ _debug("kill %lx-%lx", first, last);
+
+ count = last - first + 1;
+ if (count > PAGEVEC_SIZE)
+ count = PAGEVEC_SIZE;
+ pv.nr = find_get_pages_contig(vnode->vfs_inode.i_mapping,
+ first, count, pv.pages);
+ ASSERTCMP(pv.nr, ==, count);
+
+ for (loop = 0; loop < count; loop++) {
+ ClearPageUptodate(pv.pages[loop]);
+ if (error)
+ SetPageError(pv.pages[loop]);
+ end_page_writeback(pv.pages[loop]);
+ }
+
+ __pagevec_release(&pv);
+ } while (first < last);
+
+ _leave("");
+}
+
+/*
+ * synchronously write back the locked page and any subsequent non-locked dirty
+ * pages also covered by the same writeback record
+ */
+static int afs_write_back_from_locked_page(struct afs_writeback *wb,
+ struct page *primary_page)
+{
+ struct page *pages[8], *page;
+ unsigned long count;
+ unsigned n, offset, to;
+ pgoff_t start, first, last;
+ int loop, ret;
+
+ _enter(",%lx", primary_page->index);
+
+ count = 1;
+ if (!clear_page_dirty_for_io(primary_page))
+ BUG();
+ if (test_set_page_writeback(primary_page))
+ BUG();
+
+ /* find all consecutive lockable dirty pages, stopping when we find a
+ * page that is not immediately lockable, is not dirty or is missing,
+ * or we reach the end of the range */
+ start = primary_page->index;
+ if (start >= wb->last)
+ goto no_more;
+ start++;
+ do {
+ _debug("more %lx [%lx]", start, count);
+ n = wb->last - start + 1;
+ if (n > ARRAY_SIZE(pages))
+ n = ARRAY_SIZE(pages);
+ n = find_get_pages_contig(wb->vnode->vfs_inode.i_mapping,
+ start, n, pages);
+ _debug("fgpc %u", n);
+ if (n == 0)
+ goto no_more;
+ if (pages[0]->index != start) {
+ for (n--; n >= 0; n--)
+ put_page(pages[n]);
+ goto no_more;
+ }
+
+ for (loop = 0; loop < n; loop++) {
+ page = pages[loop];
+ if (page->index > wb->last)
+ break;
+ if (TestSetPageLocked(page))
+ break;
+ if (!PageDirty(page) ||
+ page_private(page) != (unsigned long) wb) {
+ unlock_page(page);
+ break;
+ }
+ if (!clear_page_dirty_for_io(page))
+ BUG();
+ if (test_set_page_writeback(page))
+ BUG();
+ unlock_page(page);
+ put_page(page);
+ }
+ count += loop;
+ if (loop < n) {
+ for (; loop < n; loop++)
+ put_page(pages[loop]);
+ goto no_more;
+ }
+
+ start += loop;
+ } while (start <= wb->last && count < 65536);
+
+no_more:
+ /* we now have a contiguous set of dirty pages, each with writeback set
+ * and the dirty mark cleared; the first page is locked and must remain
+ * so, all the rest are unlocked */
+ first = primary_page->index;
+ last = first + count - 1;
+
+ offset = (first == wb->first) ? wb->offset_first : 0;
+ to = (last == wb->last) ? wb->to_last : PAGE_SIZE;
+
+ _debug("write back %lx[%u..] to %lx[..%u]", first, offset, last, to);
+
+ ret = afs_vnode_store_data(wb, first, last, offset, to);
+ if (ret < 0) {
+ switch (ret) {
+ case -EDQUOT:
+ case -ENOSPC:
+ set_bit(AS_ENOSPC,
+ &wb->vnode->vfs_inode.i_mapping->flags);
+ break;
+ case -EROFS:
+ case -EIO:
+ case -EREMOTEIO:
+ case -EFBIG:
+ case -ENOENT:
+ case -ENOMEDIUM:
+ case -ENXIO:
+ afs_kill_pages(wb->vnode, true, first, last);
+ set_bit(AS_EIO, &wb->vnode->vfs_inode.i_mapping->flags);
+ break;
+ case -EACCES:
+ case -EPERM:
+ case -ENOKEY:
+ case -EKEYEXPIRED:
+ case -EKEYREJECTED:
+ case -EKEYREVOKED:
+ afs_kill_pages(wb->vnode, false, first, last);
+ break;
+ default:
+ break;
+ }
+ } else {
+ ret = count;
+ }
+
+ _leave(" = %d", ret);
+ return ret;
+}
+
+/*
+ * write a page back to the server
+ * - the caller locked the page for us
+ */
+int afs_writepage(struct page *page, struct writeback_control *wbc)
+{
+ struct backing_dev_info *bdi = page->mapping->backing_dev_info;
+ struct afs_writeback *wb;
+ int ret;
+
+ _enter("{%lx},", page->index);
+
+ if (wbc->sync_mode != WB_SYNC_NONE)
+ wait_on_page_writeback(page);
+
+ if (PageWriteback(page) || !PageDirty(page)) {
+ unlock_page(page);
+ return 0;
+ }
+
+ wb = (struct afs_writeback *) page_private(page);
+ ASSERT(wb != NULL);
+
+ ret = afs_write_back_from_locked_page(wb, page);
+ unlock_page(page);
+ if (ret < 0) {
+ _leave(" = %d", ret);
+ return 0;
+ }
+
+ wbc->nr_to_write -= ret;
+ if (wbc->nonblocking && bdi_write_congested(bdi))
+ wbc->encountered_congestion = 1;
+
+ _leave(" = 0");
+ return 0;
+}
+
+/*
+ * write a region of pages back to the server
+ */
+int afs_writepages_region(struct address_space *mapping,
+ struct writeback_control *wbc,
+ pgoff_t index, pgoff_t end, pgoff_t *_next)
+{
+ struct backing_dev_info *bdi = mapping->backing_dev_info;
+ struct afs_writeback *wb;
+ struct page *page;
+ int ret, n;
+
+ _enter(",,%lx,%lx,", index, end);
+
+ do {
+ n = find_get_pages_tag(mapping, &index, PAGECACHE_TAG_DIRTY,
+ 1, &page);
+ if (!n)
+ break;
+
+ _debug("wback %lx", page->index);
+
+ if (page->index > end) {
+ *_next = index;
+ page_cache_release(page);
+ _leave(" = 0 [%lx]", *_next);
+ return 0;
+ }
+
+ /* at this point we hold neither mapping->tree_lock nor lock on
+ * the page itself: the page may be truncated or invalidated
+ * (changing page->mapping to NULL), or even swizzled back from
+ * swapper_space to tmpfs file mapping
+ */
+ lock_page(page);
+
+ if (page->mapping != mapping) {
+ unlock_page(page);
+ page_cache_release(page);
+ continue;
+ }
+
+ if (wbc->sync_mode != WB_SYNC_NONE)
+ wait_on_page_writeback(page);
+
+ if (PageWriteback(page) || !PageDirty(page)) {
+ unlock_page(page);
+ continue;
+ }
+
+ wb = (struct afs_writeback *) page_private(page);
+ ASSERT(wb != NULL);
+
+ spin_lock(&wb->vnode->writeback_lock);
+ wb->state = AFS_WBACK_WRITING;
+ spin_unlock(&wb->vnode->writeback_lock);
+
+ ret = afs_write_back_from_locked_page(wb, page);
+ unlock_page(page);
+ page_cache_release(page);
+ if (ret < 0) {
+ _leave(" = %d", ret);
+ return ret;
+ }
+
+ wbc->nr_to_write -= ret;
+
+ if (wbc->nonblocking && bdi_write_congested(bdi)) {
+ wbc->encountered_congestion = 1;
+ break;
+ }
+
+ cond_resched();
+ } while (index < end && wbc->nr_to_write > 0);
+
+ *_next = index;
+ _leave(" = 0 [%lx]", *_next);
+ return 0;
+}
+
+/*
+ * write some of the pending data back to the server
+ */
+int afs_writepages(struct address_space *mapping,
+ struct writeback_control *wbc)
+{
+ struct backing_dev_info *bdi = mapping->backing_dev_info;
+ pgoff_t start, end, next;
+ int ret;
+
+ _enter("");
+
+ if (wbc->nonblocking && bdi_write_congested(bdi)) {
+ wbc->encountered_congestion = 1;
+ _leave(" = 0 [congest]");
+ return 0;
+ }
+
+ if (wbc->range_cyclic) {
+ start = mapping->writeback_index;
+ end = -1;
+ ret = afs_writepages_region(mapping, wbc, start, end, &next);
+ if (start > 0 && wbc->nr_to_write > 0 && ret == 0 &&
+ !(wbc->nonblocking && wbc->encountered_congestion))
+ ret = afs_writepages_region(mapping, wbc, 0, start,
+ &next);
+ mapping->writeback_index = next;
+ } else if (wbc->range_start == 0 && wbc->range_end == LLONG_MAX) {
+ end = (pgoff_t)(LLONG_MAX >> PAGE_CACHE_SHIFT);
+ ret = afs_writepages_region(mapping, wbc, 0, end, &next);
+ if (wbc->nr_to_write > 0)
+ mapping->writeback_index = next;
+ } else {
+ start = wbc->range_start >> PAGE_CACHE_SHIFT;
+ end = wbc->range_end >> PAGE_CACHE_SHIFT;
+ ret = afs_writepages_region(mapping, wbc, start, end, &next);
+ }
+
+ _leave(" = %d", ret);
+ return ret;
+}
+
+/*
+ * write an inode back
+ */
+int afs_write_inode(struct inode *inode, int sync)
+{
+ struct afs_vnode *vnode = AFS_FS_I(inode);
+ int ret;
+
+ _enter("{%x:%u},", vnode->fid.vid, vnode->fid.vnode);
+
+ ret = 0;
+ if (sync) {
+ ret = filemap_fdatawait(inode->i_mapping);
+ if (ret < 0)
+ __mark_inode_dirty(inode, I_DIRTY_DATASYNC);
+ }
+
+ _leave(" = %d", ret);
+ return ret;
+}
+
+/*
+ * completion of write to server
+ */
+void afs_pages_written_back(struct afs_vnode *vnode, struct afs_call *call)
+{
+ struct afs_writeback *wb = call->wb;
+ struct pagevec pv;
+ unsigned count, loop;
+ pgoff_t first = call->first, last = call->last;
+ bool free_wb;
+
+ _enter("{%x:%u},{%lx-%lx}",
+ vnode->fid.vid, vnode->fid.vnode, first, last);
+
+ ASSERT(wb != NULL);
+
+ pagevec_init(&pv, 0);
+
+ do {
+ _debug("attach %lx-%lx", first, last);
+
+ count = last - first + 1;
+ if (count > PAGEVEC_SIZE)
+ count = PAGEVEC_SIZE;
+ pv.nr = find_get_pages_contig(call->mapping, first, count,
+ pv.pages);
+ ASSERTCMP(pv.nr, ==, count);
+
+ spin_lock(&vnode->writeback_lock);
+ for (loop = 0; loop < count; loop++) {
+ struct page *page = pv.pages[loop];
+ end_page_writeback(page);
+ if (page_private(page) == (unsigned long) wb) {
+ set_page_private(page, 0);
+ ClearPagePrivate(page);
+ wb->usage--;
+ }
+ }
+ free_wb = false;
+ if (wb->usage == 0) {
+ afs_unlink_writeback(wb);
+ free_wb = true;
+ }
+ spin_unlock(&vnode->writeback_lock);
+ first += count;
+ if (free_wb) {
+ afs_free_writeback(wb);
+ wb = NULL;
+ }
+
+ __pagevec_release(&pv);
+ } while (first < last);
+
+ _leave("");
+}
+
+/*
+ * write to an AFS file
+ */
+ssize_t afs_file_write(struct kiocb *iocb, const struct iovec *iov,
+ unsigned long nr_segs, loff_t pos)
+{
+ struct dentry *dentry = iocb->ki_filp->f_path.dentry;
+ struct afs_vnode *vnode = AFS_FS_I(dentry->d_inode);
+ ssize_t result;
+ size_t count = iov_length(iov, nr_segs);
+ int ret;
+
+ _enter("{%x.%u},{%zu},%lu,",
+ vnode->fid.vid, vnode->fid.vnode, count, nr_segs);
+
+ if (IS_SWAPFILE(&vnode->vfs_inode)) {
+ printk(KERN_INFO
+ "AFS: Attempt to write to active swap file!\n");
+ return -EBUSY;
+ }
+
+ if (!count)
+ return 0;
+
+ result = generic_file_aio_write(iocb, iov, nr_segs, pos);
+ if (IS_ERR_VALUE(result)) {
+ _leave(" = %zd", result);
+ return result;
+ }
+
+ /* return error values for O_SYNC and IS_SYNC() */
+ if (IS_SYNC(&vnode->vfs_inode) || iocb->ki_filp->f_flags & O_SYNC) {
+ ret = afs_fsync(iocb->ki_filp, dentry, 1);
+ if (ret < 0)
+ result = ret;
+ }
+
+ _leave(" = %zd", result);
+ return result;
+}
+
+/*
+ * flush the vnode to the fileserver
+ */
+int afs_writeback_all(struct afs_vnode *vnode)
+{
+ struct address_space *mapping = vnode->vfs_inode.i_mapping;
+ struct writeback_control wbc = {
+ .bdi = mapping->backing_dev_info,
+ .sync_mode = WB_SYNC_ALL,
+ .nr_to_write = LONG_MAX,
+ .for_writepages = 1,
+ .range_cyclic = 1,
+ };
+ int ret;
+
+ _enter("");
+
+ ret = mapping->a_ops->writepages(mapping, &wbc);
+ __mark_inode_dirty(mapping->host, I_DIRTY_PAGES);
+
+ _leave(" = %d", ret);
+ return ret;
+}
+
+/*
+ * flush any dirty pages for this process, and check for write errors.
+ * - the return status from this call provides a reliable indication of
+ * whether any write errors occurred for this process.
+ */
+int afs_fsync(struct file *file, struct dentry *dentry, int datasync)
+{
+ struct afs_writeback *wb, *xwb;
+ struct afs_vnode *vnode = AFS_FS_I(dentry->d_inode);
+ int ret;
+
+ _enter("{%x:%u},{n=%s},%d",
+ vnode->fid.vid, vnode->fid.vnode, dentry->d_name.name,
+ datasync);
+
+ /* use a writeback record as a marker in the queue - when this reaches
+ * the front of the queue, all the outstanding writes are either
+ * completed or rejected */
+ wb = kzalloc(sizeof(*wb), GFP_KERNEL);
+ if (!wb)
+ return -ENOMEM;
+ wb->vnode = vnode;
+ wb->first = 0;
+ wb->last = -1;
+ wb->offset_first = 0;
+ wb->to_last = PAGE_SIZE;
+ wb->usage = 1;
+ wb->state = AFS_WBACK_SYNCING;
+ init_waitqueue_head(&wb->waitq);
+
+ spin_lock(&vnode->writeback_lock);
+ list_for_each_entry(xwb, &vnode->writebacks, link) {
+ if (xwb->state == AFS_WBACK_PENDING)
+ xwb->state = AFS_WBACK_CONFLICTING;
+ }
+ list_add_tail(&wb->link, &vnode->writebacks);
+ spin_unlock(&vnode->writeback_lock);
+
+ /* push all the outstanding writebacks to the server */
+ ret = afs_writeback_all(vnode);
+ if (ret < 0) {
+ afs_put_writeback(wb);
+ _leave(" = %d [wb]", ret);
+ return ret;
+ }
+
+ /* wait for the preceding writes to actually complete */
+ ret = wait_event_interruptible(wb->waitq,
+ wb->state == AFS_WBACK_COMPLETE ||
+ vnode->writebacks.next == &wb->link);
+ afs_put_writeback(wb);
+ _leave(" = %d", ret);
+ return ret;
+}
projects / linux-2.6 / commitdiff