#include <linux/pipe_fs_i.h>
#include <linux/swap.h>
#include <linux/splice.h>
+ #include <linux/aio.h>
MODULE_ALIAS_MISCDEV(FUSE_MINOR);
MODULE_ALIAS("devname:fuse");
sigprocmask(SIG_SETMASK, oldset, NULL);
}
-static void __fuse_get_request(struct fuse_req *req)
+void __fuse_get_request(struct fuse_req *req)
{
atomic_inc(&req->count);
}
req->in.h.pid = current->pid;
}
-struct fuse_req *fuse_get_req(struct fuse_conn *fc, unsigned npages)
+static bool fuse_block_alloc(struct fuse_conn *fc, bool for_background)
+{
+ return !fc->initialized || (for_background && fc->blocked);
+}
+
+static struct fuse_req *__fuse_get_req(struct fuse_conn *fc, unsigned npages,
+ bool for_background)
{
struct fuse_req *req;
- sigset_t oldset;
- int intr;
int err;
-
atomic_inc(&fc->num_waiting);
- block_sigs(&oldset);
- intr = wait_event_interruptible(fc->blocked_waitq, !fc->blocked);
- restore_sigs(&oldset);
- err = -EINTR;
- if (intr)
- goto out;
+
+ if (fuse_block_alloc(fc, for_background)) {
+ sigset_t oldset;
+ int intr;
+
+ block_sigs(&oldset);
+ intr = wait_event_interruptible_exclusive(fc->blocked_waitq,
+ !fuse_block_alloc(fc, for_background));
+ restore_sigs(&oldset);
+ err = -EINTR;
+ if (intr)
+ goto out;
+ }
err = -ENOTCONN;
if (!fc->connected)
req = fuse_request_alloc(npages);
err = -ENOMEM;
- if (!req)
+ if (!req) {
+ if (for_background)
+ wake_up(&fc->blocked_waitq);
goto out;
+ }
fuse_req_init_context(req);
req->waiting = 1;
+ req->background = for_background;
return req;
out:
atomic_dec(&fc->num_waiting);
return ERR_PTR(err);
}
+
+struct fuse_req *fuse_get_req(struct fuse_conn *fc, unsigned npages)
+{
+ return __fuse_get_req(fc, npages, false);
+}
EXPORT_SYMBOL_GPL(fuse_get_req);
+struct fuse_req *fuse_get_req_for_background(struct fuse_conn *fc,
+ unsigned npages)
+{
+ return __fuse_get_req(fc, npages, true);
+}
+EXPORT_SYMBOL_GPL(fuse_get_req_for_background);
+
/*
* Return request in fuse_file->reserved_req. However that may
* currently be in use. If that is the case, wait for it to become
struct fuse_req *req;
atomic_inc(&fc->num_waiting);
- wait_event(fc->blocked_waitq, !fc->blocked);
+ wait_event(fc->blocked_waitq, fc->initialized);
req = fuse_request_alloc(0);
if (!req)
req = get_reserved_req(fc, file);
fuse_req_init_context(req);
req->waiting = 1;
+ req->background = 0;
return req;
}
void fuse_put_request(struct fuse_conn *fc, struct fuse_req *req)
{
if (atomic_dec_and_test(&req->count)) {
+ if (unlikely(req->background)) {
+ /*
+ * We get here in the unlikely case that a background
+ * request was allocated but not sent
+ */
+ spin_lock(&fc->lock);
+ if (!fc->blocked)
+ wake_up(&fc->blocked_waitq);
+ spin_unlock(&fc->lock);
+ }
+
if (req->waiting)
atomic_dec(&fc->num_waiting);
list_del(&req->intr_entry);
req->state = FUSE_REQ_FINISHED;
if (req->background) {
- if (fc->num_background == fc->max_background) {
+ req->background = 0;
+
+ if (fc->num_background == fc->max_background)
fc->blocked = 0;
- wake_up_all(&fc->blocked_waitq);
- }
+
+ /* Wake up next waiter, if any */
+ if (!fc->blocked && waitqueue_active(&fc->blocked_waitq))
+ wake_up(&fc->blocked_waitq);
+
if (fc->num_background == fc->congestion_threshold &&
fc->connected && fc->bdi_initialized) {
clear_bdi_congested(&fc->bdi, BLK_RW_SYNC);
static void __fuse_request_send(struct fuse_conn *fc, struct fuse_req *req)
{
+ BUG_ON(req->background);
spin_lock(&fc->lock);
if (!fc->connected)
req->out.h.error = -ENOTCONN;
static void fuse_request_send_nowait_locked(struct fuse_conn *fc,
struct fuse_req *req)
{
- req->background = 1;
+ BUG_ON(!req->background);
fc->num_background++;
if (fc->num_background == fc->max_background)
fc->blocked = 1;
if (fc->connected) {
fc->connected = 0;
fc->blocked = 0;
+ fc->initialized = 1;
end_io_requests(fc);
end_queued_requests(fc);
end_polls(fc);
spin_lock(&fc->lock);
fc->connected = 0;
fc->blocked = 0;
+ fc->initialized = 1;
end_queued_requests(fc);
end_polls(fc);
wake_up_all(&fc->blocked_waitq);
#include <linux/module.h>
#include <linux/compat.h>
#include <linux/swap.h>
+ #include <linux/aio.h>
static const struct file_operations fuse_direct_io_file_operations;
struct fuse_req *req = ff->reserved_req;
if (sync) {
+ req->background = 0;
fuse_request_send(ff->fc, req);
path_put(&req->misc.release.path);
fuse_put_request(ff->fc, req);
} else {
req->end = fuse_release_end;
+ req->background = 1;
fuse_request_send_background(ff->fc, req);
}
kfree(ff);
WARN_ON(atomic_read(&ff->count) > 1);
fuse_prepare_release(ff, flags, FUSE_RELEASE);
ff->reserved_req->force = 1;
+ ff->reserved_req->background = 0;
fuse_request_send(ff->fc, ff->reserved_req);
fuse_put_request(ff->fc, ff->reserved_req);
kfree(ff);
req->out.args[0].size = count;
}
-static size_t fuse_send_read(struct fuse_req *req, struct file *file,
+static void fuse_release_user_pages(struct fuse_req *req, int write)
+{
+ unsigned i;
+
+ for (i = 0; i < req->num_pages; i++) {
+ struct page *page = req->pages[i];
+ if (write)
+ set_page_dirty_lock(page);
+ put_page(page);
+ }
+}
+
+/**
+ * In case of short read, the caller sets 'pos' to the position of
+ * actual end of fuse request in IO request. Otherwise, if bytes_requested
+ * == bytes_transferred or rw == WRITE, the caller sets 'pos' to -1.
+ *
+ * An example:
+ * User requested DIO read of 64K. It was splitted into two 32K fuse requests,
+ * both submitted asynchronously. The first of them was ACKed by userspace as
+ * fully completed (req->out.args[0].size == 32K) resulting in pos == -1. The
+ * second request was ACKed as short, e.g. only 1K was read, resulting in
+ * pos == 33K.
+ *
+ * Thus, when all fuse requests are completed, the minimal non-negative 'pos'
+ * will be equal to the length of the longest contiguous fragment of
+ * transferred data starting from the beginning of IO request.
+ */
+static void fuse_aio_complete(struct fuse_io_priv *io, int err, ssize_t pos)
+{
+ int left;
+
+ spin_lock(&io->lock);
+ if (err)
+ io->err = io->err ? : err;
+ else if (pos >= 0 && (io->bytes < 0 || pos < io->bytes))
+ io->bytes = pos;
+
+ left = --io->reqs;
+ spin_unlock(&io->lock);
+
+ if (!left) {
+ long res;
+
+ if (io->err)
+ res = io->err;
+ else if (io->bytes >= 0 && io->write)
+ res = -EIO;
+ else {
+ res = io->bytes < 0 ? io->size : io->bytes;
+
+ if (!is_sync_kiocb(io->iocb)) {
+ struct path *path = &io->iocb->ki_filp->f_path;
+ struct inode *inode = path->dentry->d_inode;
+ struct fuse_conn *fc = get_fuse_conn(inode);
+ struct fuse_inode *fi = get_fuse_inode(inode);
+
+ spin_lock(&fc->lock);
+ fi->attr_version = ++fc->attr_version;
+ spin_unlock(&fc->lock);
+ }
+ }
+
+ aio_complete(io->iocb, res, 0);
+ kfree(io);
+ }
+}
+
+static void fuse_aio_complete_req(struct fuse_conn *fc, struct fuse_req *req)
+{
+ struct fuse_io_priv *io = req->io;
+ ssize_t pos = -1;
+
+ fuse_release_user_pages(req, !io->write);
+
+ if (io->write) {
+ if (req->misc.write.in.size != req->misc.write.out.size)
+ pos = req->misc.write.in.offset - io->offset +
+ req->misc.write.out.size;
+ } else {
+ if (req->misc.read.in.size != req->out.args[0].size)
+ pos = req->misc.read.in.offset - io->offset +
+ req->out.args[0].size;
+ }
+
+ fuse_aio_complete(io, req->out.h.error, pos);
+}
+
+static size_t fuse_async_req_send(struct fuse_conn *fc, struct fuse_req *req,
+ size_t num_bytes, struct fuse_io_priv *io)
+{
+ spin_lock(&io->lock);
+ io->size += num_bytes;
+ io->reqs++;
+ spin_unlock(&io->lock);
+
+ req->io = io;
+ req->end = fuse_aio_complete_req;
+
+ __fuse_get_request(req);
+ fuse_request_send_background(fc, req);
+
+ return num_bytes;
+}
+
+static size_t fuse_send_read(struct fuse_req *req, struct fuse_io_priv *io,
loff_t pos, size_t count, fl_owner_t owner)
{
+ struct file *file = io->file;
struct fuse_file *ff = file->private_data;
struct fuse_conn *fc = ff->fc;
inarg->read_flags |= FUSE_READ_LOCKOWNER;
inarg->lock_owner = fuse_lock_owner_id(fc, owner);
}
+
+ if (io->async)
+ return fuse_async_req_send(fc, req, count, io);
+
fuse_request_send(fc, req);
return req->out.args[0].size;
}
static int fuse_readpage(struct file *file, struct page *page)
{
+ struct fuse_io_priv io = { .async = 0, .file = file };
struct inode *inode = page->mapping->host;
struct fuse_conn *fc = get_fuse_conn(inode);
struct fuse_req *req;
req->num_pages = 1;
req->pages[0] = page;
req->page_descs[0].length = count;
- num_read = fuse_send_read(req, file, pos, count, NULL);
+ num_read = fuse_send_read(req, &io, pos, count, NULL);
err = req->out.h.error;
fuse_put_request(fc, req);
int nr_alloc = min_t(unsigned, data->nr_pages,
FUSE_MAX_PAGES_PER_REQ);
fuse_send_readpages(req, data->file);
- data->req = req = fuse_get_req(fc, nr_alloc);
+ if (fc->async_read)
+ req = fuse_get_req_for_background(fc, nr_alloc);
+ else
+ req = fuse_get_req(fc, nr_alloc);
+
+ data->req = req;
if (IS_ERR(req)) {
unlock_page(page);
return PTR_ERR(req);
data.file = file;
data.inode = inode;
- data.req = fuse_get_req(fc, nr_alloc);
+ if (fc->async_read)
+ data.req = fuse_get_req_for_background(fc, nr_alloc);
+ else
+ data.req = fuse_get_req(fc, nr_alloc);
data.nr_pages = nr_pages;
err = PTR_ERR(data.req);
if (IS_ERR(data.req))
req->out.args[0].value = outarg;
}
-static size_t fuse_send_write(struct fuse_req *req, struct file *file,
+static size_t fuse_send_write(struct fuse_req *req, struct fuse_io_priv *io,
loff_t pos, size_t count, fl_owner_t owner)
{
+ struct file *file = io->file;
struct fuse_file *ff = file->private_data;
struct fuse_conn *fc = ff->fc;
struct fuse_write_in *inarg = &req->misc.write.in;
inarg->write_flags |= FUSE_WRITE_LOCKOWNER;
inarg->lock_owner = fuse_lock_owner_id(fc, owner);
}
+
+ if (io->async)
+ return fuse_async_req_send(fc, req, count, io);
+
fuse_request_send(fc, req);
return req->misc.write.out.size;
}
size_t res;
unsigned offset;
unsigned i;
+ struct fuse_io_priv io = { .async = 0, .file = file };
for (i = 0; i < req->num_pages; i++)
fuse_wait_on_page_writeback(inode, req->pages[i]->index);
- res = fuse_send_write(req, file, pos, count, NULL);
+ res = fuse_send_write(req, &io, pos, count, NULL);
offset = req->page_descs[0].offset;
count = res;
return written ? written : err;
}
-static void fuse_release_user_pages(struct fuse_req *req, int write)
-{
- unsigned i;
-
- for (i = 0; i < req->num_pages; i++) {
- struct page *page = req->pages[i];
- if (write)
- set_page_dirty_lock(page);
- put_page(page);
- }
-}
-
static inline void fuse_page_descs_length_init(struct fuse_req *req,
unsigned index, unsigned nr_pages)
{
return min(npages, FUSE_MAX_PAGES_PER_REQ);
}
-ssize_t fuse_direct_io(struct file *file, const struct iovec *iov,
+ssize_t fuse_direct_io(struct fuse_io_priv *io, const struct iovec *iov,
unsigned long nr_segs, size_t count, loff_t *ppos,
int write)
{
+ struct file *file = io->file;
struct fuse_file *ff = file->private_data;
struct fuse_conn *fc = ff->fc;
size_t nmax = write ? fc->max_write : fc->max_read;
}
if (write)
- nres = fuse_send_write(req, file, pos, nbytes, owner);
+ nres = fuse_send_write(req, io, pos, nbytes, owner);
else
- nres = fuse_send_read(req, file, pos, nbytes, owner);
+ nres = fuse_send_read(req, io, pos, nbytes, owner);
- fuse_release_user_pages(req, !write);
+ if (!io->async)
+ fuse_release_user_pages(req, !write);
if (req->out.h.error) {
if (!res)
res = req->out.h.error;
}
EXPORT_SYMBOL_GPL(fuse_direct_io);
-static ssize_t __fuse_direct_read(struct file *file, const struct iovec *iov,
- unsigned long nr_segs, loff_t *ppos)
+static ssize_t __fuse_direct_read(struct fuse_io_priv *io,
+ const struct iovec *iov,
+ unsigned long nr_segs, loff_t *ppos,
+ size_t count)
{
ssize_t res;
+ struct file *file = io->file;
struct inode *inode = file_inode(file);
if (is_bad_inode(inode))
return -EIO;
- res = fuse_direct_io(file, iov, nr_segs, iov_length(iov, nr_segs),
- ppos, 0);
+ res = fuse_direct_io(io, iov, nr_segs, count, ppos, 0);
fuse_invalidate_attr(inode);
static ssize_t fuse_direct_read(struct file *file, char __user *buf,
size_t count, loff_t *ppos)
{
+ struct fuse_io_priv io = { .async = 0, .file = file };
struct iovec iov = { .iov_base = buf, .iov_len = count };
- return __fuse_direct_read(file, &iov, 1, ppos);
+ return __fuse_direct_read(&io, &iov, 1, ppos, count);
}
-static ssize_t __fuse_direct_write(struct file *file, const struct iovec *iov,
+static ssize_t __fuse_direct_write(struct fuse_io_priv *io,
+ const struct iovec *iov,
unsigned long nr_segs, loff_t *ppos)
{
+ struct file *file = io->file;
struct inode *inode = file_inode(file);
size_t count = iov_length(iov, nr_segs);
ssize_t res;
res = generic_write_checks(file, ppos, &count, 0);
- if (!res) {
- res = fuse_direct_io(file, iov, nr_segs, count, ppos, 1);
- if (res > 0)
- fuse_write_update_size(inode, *ppos);
- }
+ if (!res)
+ res = fuse_direct_io(io, iov, nr_segs, count, ppos, 1);
fuse_invalidate_attr(inode);
struct iovec iov = { .iov_base = (void __user *)buf, .iov_len = count };
struct inode *inode = file_inode(file);
ssize_t res;
+ struct fuse_io_priv io = { .async = 0, .file = file };
if (is_bad_inode(inode))
return -EIO;
/* Don't allow parallel writes to the same file */
mutex_lock(&inode->i_mutex);
- res = __fuse_direct_write(file, &iov, 1, ppos);
+ res = __fuse_direct_write(&io, &iov, 1, ppos);
+ if (res > 0)
+ fuse_write_update_size(inode, *ppos);
mutex_unlock(&inode->i_mutex);
return res;
if (!req)
goto err;
+ req->background = 1; /* writeback always goes to bg_queue */
tmp_page = alloc_page(GFP_NOFS | __GFP_HIGHMEM);
if (!tmp_page)
goto err_free;
return 0;
}
+static void fuse_do_truncate(struct file *file)
+{
+ struct inode *inode = file->f_mapping->host;
+ struct iattr attr;
+
+ attr.ia_valid = ATTR_SIZE;
+ attr.ia_size = i_size_read(inode);
+
+ attr.ia_file = file;
+ attr.ia_valid |= ATTR_FILE;
+
+ fuse_do_setattr(inode, &attr, file);
+}
+
static ssize_t
fuse_direct_IO(int rw, struct kiocb *iocb, const struct iovec *iov,
loff_t offset, unsigned long nr_segs)
{
ssize_t ret = 0;
- struct file *file = NULL;
+ struct file *file = iocb->ki_filp;
+ struct fuse_file *ff = file->private_data;
loff_t pos = 0;
+ struct inode *inode;
+ loff_t i_size;
+ size_t count = iov_length(iov, nr_segs);
+ struct fuse_io_priv *io;
- file = iocb->ki_filp;
pos = offset;
+ inode = file->f_mapping->host;
+ i_size = i_size_read(inode);
+
+ /* optimization for short read */
+ if (rw != WRITE && offset + count > i_size) {
+ if (offset >= i_size)
+ return 0;
+ count = i_size - offset;
+ }
+
+ io = kmalloc(sizeof(struct fuse_io_priv), GFP_KERNEL);
+ if (!io)
+ return -ENOMEM;
+ spin_lock_init(&io->lock);
+ io->reqs = 1;
+ io->bytes = -1;
+ io->size = 0;
+ io->offset = offset;
+ io->write = (rw == WRITE);
+ io->err = 0;
+ io->file = file;
+ /*
+ * By default, we want to optimize all I/Os with async request
+ * submission to the client filesystem if supported.
+ */
+ io->async = ff->fc->async_dio;
+ io->iocb = iocb;
+
+ /*
+ * We cannot asynchronously extend the size of a file. We have no method
+ * to wait on real async I/O requests, so we must submit this request
+ * synchronously.
+ */
+ if (!is_sync_kiocb(iocb) && (offset + count > i_size))
+ io->async = false;
if (rw == WRITE)
- ret = __fuse_direct_write(file, iov, nr_segs, &pos);
+ ret = __fuse_direct_write(io, iov, nr_segs, &pos);
else
- ret = __fuse_direct_read(file, iov, nr_segs, &pos);
+ ret = __fuse_direct_read(io, iov, nr_segs, &pos, count);
+
+ if (io->async) {
+ fuse_aio_complete(io, ret < 0 ? ret : 0, -1);
+
+ /* we have a non-extending, async request, so return */
+ if (ret > 0 && !is_sync_kiocb(iocb))
+ return -EIOCBQUEUED;
+
+ ret = wait_on_sync_kiocb(iocb);
+ } else {
+ kfree(io);
+ }
+
+ if (rw == WRITE) {
+ if (ret > 0)
+ fuse_write_update_size(inode, pos);
+ else if (ret < 0 && offset + count > i_size)
+ fuse_do_truncate(file);
+ }
return ret;
}
git.openpandora.org / pandora-kernel.git / commitdiff