From 36cf66ed9f871fc0d0911921fba5873df3ddb2dc Mon Sep 17 00:00:00 2001 From: Maxim Patlasov Date: Fri, 14 Dec 2012 19:20:51 +0400 Subject: [PATCH] fuse: make fuse_direct_io() aware about AIO The patch implements passing "struct fuse_io_priv *io" down the stack up to fuse_send_read/write where it is used to submit request asynchronously. io->async==0 designates synchronous processing. Non-trivial part of the patch is changes in fuse_direct_io(): resources like fuse requests and user pages cannot be released immediately in async case. Signed-off-by: Maxim Patlasov Signed-off-by: Miklos Szeredi --- fs/fuse/cuse.c | 6 +++-- fs/fuse/dev.c | 2 +- fs/fuse/file.c | 64 +++++++++++++++++++++++++++++++++++------------- fs/fuse/fuse_i.h | 7 +++++- 4 files changed, 58 insertions(+), 21 deletions(-) diff --git a/fs/fuse/cuse.c b/fs/fuse/cuse.c index c59c097eb2e9..b3aaf7b3578b 100644 --- a/fs/fuse/cuse.c +++ b/fs/fuse/cuse.c @@ -92,8 +92,9 @@ static ssize_t cuse_read(struct file *file, char __user *buf, size_t count, { loff_t pos = 0; struct iovec iov = { .iov_base = buf, .iov_len = count }; + struct fuse_io_priv io = { .async = 0, .file = file }; - return fuse_direct_io(file, &iov, 1, count, &pos, 0); + return fuse_direct_io(&io, &iov, 1, count, &pos, 0); } static ssize_t cuse_write(struct file *file, const char __user *buf, @@ -101,12 +102,13 @@ static ssize_t cuse_write(struct file *file, const char __user *buf, { loff_t pos = 0; struct iovec iov = { .iov_base = (void __user *)buf, .iov_len = count }; + struct fuse_io_priv io = { .async = 0, .file = file }; /* * No locking or generic_write_checks(), the server is * responsible for locking and sanity checks. */ - return fuse_direct_io(file, &iov, 1, count, &pos, 1); + return fuse_direct_io(&io, &iov, 1, count, &pos, 1); } static int cuse_open(struct inode *inode, struct file *file) diff --git a/fs/fuse/dev.c b/fs/fuse/dev.c index be5c7e13320c..07bdb14ae7a3 100644 --- a/fs/fuse/dev.c +++ b/fs/fuse/dev.c @@ -111,7 +111,7 @@ static void restore_sigs(sigset_t *oldset) 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); } diff --git a/fs/fuse/file.c b/fs/fuse/file.c index 4002889fbcc1..e207dcdf32c0 100644 --- a/fs/fuse/file.c +++ b/fs/fuse/file.c @@ -593,14 +593,16 @@ static size_t fuse_async_req_send(struct fuse_conn *fc, struct fuse_req *req, 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 file *file, +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; @@ -611,6 +613,10 @@ static size_t fuse_send_read(struct fuse_req *req, struct file *file, 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; } @@ -631,6 +637,7 @@ static void fuse_read_update_size(struct inode *inode, loff_t 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; @@ -663,7 +670,7 @@ static int fuse_readpage(struct file *file, struct page *page) 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); @@ -873,9 +880,10 @@ static void fuse_write_fill(struct fuse_req *req, struct fuse_file *ff, 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; @@ -886,6 +894,10 @@ static size_t fuse_send_write(struct fuse_req *req, struct file *file, 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; } @@ -909,11 +921,12 @@ static size_t fuse_send_write_pages(struct fuse_req *req, struct file *file, 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; @@ -1251,10 +1264,11 @@ static inline int fuse_iter_npages(const struct iov_iter *ii_p) 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; @@ -1280,11 +1294,12 @@ ssize_t fuse_direct_io(struct file *file, const struct iovec *iov, } 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; @@ -1314,16 +1329,18 @@ ssize_t fuse_direct_io(struct file *file, const struct iovec *iov, } EXPORT_SYMBOL_GPL(fuse_direct_io); -static ssize_t __fuse_direct_read(struct file *file, const struct iovec *iov, +static ssize_t __fuse_direct_read(struct fuse_io_priv *io, + const struct iovec *iov, unsigned long nr_segs, loff_t *ppos) { 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), + res = fuse_direct_io(io, iov, nr_segs, iov_length(iov, nr_segs), ppos, 0); fuse_invalidate_attr(inode); @@ -1334,21 +1351,24 @@ static ssize_t __fuse_direct_read(struct file *file, const struct iovec *iov, 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); } -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) + res = fuse_direct_io(io, iov, nr_segs, count, ppos, 1); + if (!io->async && res > 0) fuse_write_update_size(inode, *ppos); } @@ -1363,13 +1383,14 @@ static ssize_t fuse_direct_write(struct file *file, const char __user *buf, 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); mutex_unlock(&inode->i_mutex); return res; @@ -2339,14 +2360,23 @@ fuse_direct_IO(int rw, struct kiocb *iocb, const struct iovec *iov, ssize_t ret = 0; struct file *file = NULL; loff_t pos = 0; + struct fuse_io_priv *io; file = iocb->ki_filp; pos = offset; + io = kzalloc(sizeof(struct fuse_io_priv), GFP_KERNEL); + if (!io) + return -ENOMEM; + + io->file = file; + 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); + + kfree(io); return ret; } diff --git a/fs/fuse/fuse_i.h b/fs/fuse/fuse_i.h index aea072413c47..337169a406c9 100644 --- a/fs/fuse/fuse_i.h +++ b/fs/fuse/fuse_i.h @@ -732,6 +732,11 @@ struct fuse_req *fuse_get_req(struct fuse_conn *fc, unsigned npages); struct fuse_req *fuse_get_req_for_background(struct fuse_conn *fc, unsigned npages); +/* + * Increment reference count on request + */ +void __fuse_get_request(struct fuse_req *req); + /** * Get a request, may fail with -ENOMEM, * useful for callers who doesn't use req->pages[] @@ -846,7 +851,7 @@ int fuse_reverse_inval_entry(struct super_block *sb, u64 parent_nodeid, int fuse_do_open(struct fuse_conn *fc, u64 nodeid, struct file *file, bool isdir); -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); long fuse_do_ioctl(struct file *file, unsigned int cmd, unsigned long arg, -- GitLab