return 0;
/* Try lock this page */
- if (buf->ops->steal(pipe, buf) == 0) {
+ if (pipe_buf_steal(pipe, buf) == 0) {
/* Get reference and unlock page for moving */
get_page(buf->page);
unlock_page(buf->page);
range_lock_init(&range, *ppos, *ppos + count - 1);
vio->vui_fd = LUSTRE_FPRIVATE(file);
- vio->vui_io_subtype = args->via_io_subtype;
+ vio->vui_iter = args->u.normal.via_iter;
+ vio->vui_iocb = args->u.normal.via_iocb;
+ /*
+ * Direct IO reads must also take range lock,
+ * or multiple reads will try to work on the same pages
+ * See LU-6227 for details.
+ */
+ if (((iot == CIT_WRITE) ||
+ (iot == CIT_READ && (file->f_flags & O_DIRECT))) &&
+ !(vio->vui_fd->fd_flags & LL_FILE_GROUP_LOCKED)) {
+ CDEBUG(D_VFSTRACE, "Range lock [%llu, %llu]\n",
+ range.rl_node.in_extent.start,
+ range.rl_node.in_extent.end);
+ result = range_lock(&lli->lli_write_tree,
+ &range);
+ if (result < 0)
+ goto out;
- switch (vio->vui_io_subtype) {
- case IO_NORMAL:
- vio->vui_iter = args->u.normal.via_iter;
- vio->vui_iocb = args->u.normal.via_iocb;
- /*
- * Direct IO reads must also take range lock,
- * or multiple reads will try to work on the same pages
- * See LU-6227 for details.
- */
- if (((iot == CIT_WRITE) ||
- (iot == CIT_READ && (file->f_flags & O_DIRECT))) &&
- !(vio->vui_fd->fd_flags & LL_FILE_GROUP_LOCKED)) {
- CDEBUG(D_VFSTRACE, "Range lock [%llu, %llu]\n",
- range.rl_node.in_extent.start,
- range.rl_node.in_extent.end);
- result = range_lock(&lli->lli_write_tree,
- &range);
- if (result < 0)
- goto out;
-
- range_locked = true;
- }
- down_read(&lli->lli_trunc_sem);
- break;
- case IO_SPLICE:
- vio->u.splice.vui_pipe = args->u.splice.via_pipe;
- vio->u.splice.vui_flags = args->u.splice.via_flags;
- break;
- default:
- CERROR("Unknown IO type - %u\n", vio->vui_io_subtype);
- LBUG();
+ range_locked = true;
}
+ down_read(&lli->lli_trunc_sem);
ll_cl_add(file, env, io);
result = cl_io_loop(env, io);
ll_cl_remove(file, env);
- if (args->via_io_subtype == IO_NORMAL)
- up_read(&lli->lli_trunc_sem);
+ up_read(&lli->lli_trunc_sem);
if (range_locked) {
CDEBUG(D_VFSTRACE, "Range unlock [%llu, %llu]\n",
range.rl_node.in_extent.start,
if (IS_ERR(env))
return PTR_ERR(env);
- args = ll_env_args(env, IO_NORMAL);
+ args = ll_env_args(env);
args->u.normal.via_iter = to;
args->u.normal.via_iocb = iocb;
if (IS_ERR(env))
return PTR_ERR(env);
- args = ll_env_args(env, IO_NORMAL);
+ args = ll_env_args(env);
args->u.normal.via_iter = from;
args->u.normal.via_iocb = iocb;
return result;
}
-/*
- * Send file content (through pagecache) somewhere with helper
- */
-static ssize_t ll_file_splice_read(struct file *in_file, loff_t *ppos,
- struct pipe_inode_info *pipe, size_t count,
- unsigned int flags)
-{
- struct lu_env *env;
- struct vvp_io_args *args;
- ssize_t result;
- int refcheck;
-
- env = cl_env_get(&refcheck);
- if (IS_ERR(env))
- return PTR_ERR(env);
-
- args = ll_env_args(env, IO_SPLICE);
- args->u.splice.via_pipe = pipe;
- args->u.splice.via_flags = flags;
-
- result = ll_file_io_generic(env, args, in_file, CIT_READ, ppos, count);
- cl_env_put(env, &refcheck);
- return result;
-}
-
int ll_lov_setstripe_ea_info(struct inode *inode, struct dentry *dentry,
__u64 flags, struct lov_user_md *lum,
int lum_size)
.release = ll_file_release,
.mmap = ll_file_mmap,
.llseek = ll_file_seek,
- .splice_read = ll_file_splice_read,
+ .splice_read = generic_file_splice_read,
.fsync = ll_fsync,
.flush = ll_flush
};
.release = ll_file_release,
.mmap = ll_file_mmap,
.llseek = ll_file_seek,
- .splice_read = ll_file_splice_read,
+ .splice_read = generic_file_splice_read,
.fsync = ll_fsync,
.flush = ll_flush,
.flock = ll_file_flock,
.release = ll_file_release,
.mmap = ll_file_mmap,
.llseek = ll_file_seek,
- .splice_read = ll_file_splice_read,
+ .splice_read = generic_file_splice_read,
.fsync = ll_fsync,
.flush = ll_flush,
.flock = ll_file_noflock,
*/
struct vvp_io_args {
/** normal/splice */
- enum vvp_io_subtype via_io_subtype;
-
union {
struct {
struct kiocb *via_iocb;
struct iov_iter *via_iter;
} normal;
- struct {
- struct pipe_inode_info *via_pipe;
- unsigned int via_flags;
- } splice;
} u;
};
return lti;
}
-static inline struct vvp_io_args *ll_env_args(const struct lu_env *env,
- enum vvp_io_subtype type)
+static inline struct vvp_io_args *ll_env_args(const struct lu_env *env)
{
- struct vvp_io_args *via = &ll_env_info(env)->lti_args;
-
- via->via_io_subtype = type;
-
- return via;
+ return &ll_env_info(env)->lti_args;
}
void ll_queue_done_writing(struct inode *inode, unsigned long flags);
struct obd_export;
struct page;
-/* specific architecture can implement only part of this list */
-enum vvp_io_subtype {
- /** normal IO */
- IO_NORMAL,
- /** io started from splice_{read|write} */
- IO_SPLICE
-};
-
/**
* IO state private to IO state private to VVP layer.
*/
*/
bool ft_flags_valid;
} fault;
- struct {
- struct pipe_inode_info *vui_pipe;
- unsigned int vui_flags;
- } splice;
struct {
struct cl_page_list vui_queue;
unsigned long vui_written;
} write;
} u;
- enum vvp_io_subtype vui_io_subtype;
-
/**
* Layout version when this IO is initialized
*/
return vio;
}
-/**
- * True, if \a io is a normal io, False for splice_{read,write}
- */
-static int cl_is_normalio(const struct lu_env *env, const struct cl_io *io)
-{
- struct vvp_io *vio = vvp_env_io(env);
-
- LASSERT(io->ci_type == CIT_READ || io->ci_type == CIT_WRITE);
-
- return vio->vui_io_subtype == IO_NORMAL;
-}
-
/**
* For swapping layout. The file's layout may have changed.
* To avoid populating pages to a wrong stripe, we have to verify the
LASSERT(io->ci_type == CIT_READ || io->ci_type == CIT_WRITE);
- if (!cl_is_normalio(env, io))
- return 0;
-
if (!vio->vui_iter) /* nfs or loop back device write */
return 0;
const struct cl_io_slice *ios,
size_t nob)
{
- struct vvp_io *vio = cl2vvp_io(env, ios);
- struct cl_io *io = ios->cis_io;
struct cl_object *obj = ios->cis_io->ci_obj;
-
+ struct vvp_io *vio = cl2vvp_io(env, ios);
CLOBINVRNT(env, obj, vvp_object_invariant(obj));
- if (!cl_is_normalio(env, io))
- return;
-
iov_iter_reexpand(vio->vui_iter, vio->vui_tot_count -= nob);
}
{
size_t size = io->u.ci_rw.crw_count;
- if (!cl_is_normalio(env, io) || !vio->vui_iter)
+ if (!vio->vui_iter)
return;
iov_iter_truncate(vio->vui_iter, size);
/* BUG: 5972 */
file_accessed(file);
- switch (vio->vui_io_subtype) {
- case IO_NORMAL:
- LASSERT(vio->vui_iocb->ki_pos == pos);
- result = generic_file_read_iter(vio->vui_iocb, vio->vui_iter);
- break;
- case IO_SPLICE:
- result = generic_file_splice_read(file, &pos,
- vio->u.splice.vui_pipe, cnt,
- vio->u.splice.vui_flags);
- /* LU-1109: do splice read stripe by stripe otherwise if it
- * may make nfsd stuck if this read occupied all internal pipe
- * buffers.
- */
- io->ci_continue = 0;
- break;
- default:
- CERROR("Wrong IO type %u\n", vio->vui_io_subtype);
- LBUG();
- }
+ LASSERT(vio->vui_iocb->ki_pos == pos);
+ result = generic_file_read_iter(vio->vui_iocb, vio->vui_iter);
out:
if (result >= 0) {
return vfs_iter_read(cfi->cfi_container, to, &iocb->ki_pos);
}
-static ssize_t
-coda_file_splice_read(struct file *coda_file, loff_t *ppos,
- struct pipe_inode_info *pipe, size_t count,
- unsigned int flags)
-{
- ssize_t (*splice_read)(struct file *, loff_t *,
- struct pipe_inode_info *, size_t, unsigned int);
- struct coda_file_info *cfi;
- struct file *host_file;
-
- cfi = CODA_FTOC(coda_file);
- BUG_ON(!cfi || cfi->cfi_magic != CODA_MAGIC);
- host_file = cfi->cfi_container;
-
- splice_read = host_file->f_op->splice_read;
- if (!splice_read)
- splice_read = default_file_splice_read;
-
- return splice_read(host_file, ppos, pipe, count, flags);
-}
-
static ssize_t
coda_file_write_iter(struct kiocb *iocb, struct iov_iter *to)
{
.open = coda_open,
.release = coda_release,
.fsync = coda_fsync,
- .splice_read = coda_file_splice_read,
+ .splice_read = generic_file_splice_read,
};
if ((dio->op == REQ_OP_READ) &&
((offset + transferred) > dio->i_size))
transferred = dio->i_size - offset;
+ /* ignore EFAULT if some IO has been done */
+ if (unlikely(ret == -EFAULT) && transferred)
+ ret = 0;
}
if (ret == 0)
struct pipe_buffer *buf = cs->pipebufs;
if (!cs->write) {
- err = buf->ops->confirm(cs->pipe, buf);
+ err = pipe_buf_confirm(cs->pipe, buf);
if (err)
return err;
fuse_copy_finish(cs);
- err = buf->ops->confirm(cs->pipe, buf);
+ err = pipe_buf_confirm(cs->pipe, buf);
if (err)
return err;
if (cs->len != PAGE_SIZE)
goto out_fallback;
- if (buf->ops->steal(cs->pipe, buf) != 0)
+ if (pipe_buf_steal(cs->pipe, buf) != 0)
goto out_fallback;
newpage = buf->page;
struct pipe_inode_info *pipe,
size_t len, unsigned int flags)
{
- int ret;
+ int total, ret;
int page_nr = 0;
- int do_wakeup = 0;
struct pipe_buffer *bufs;
struct fuse_copy_state cs;
struct fuse_dev *fud = fuse_get_dev(in);
if (ret < 0)
goto out;
- ret = 0;
- pipe_lock(pipe);
-
- if (!pipe->readers) {
- send_sig(SIGPIPE, current, 0);
- if (!ret)
- ret = -EPIPE;
- goto out_unlock;
- }
-
if (pipe->nrbufs + cs.nr_segs > pipe->buffers) {
ret = -EIO;
- goto out_unlock;
+ goto out;
}
- while (page_nr < cs.nr_segs) {
- int newbuf = (pipe->curbuf + pipe->nrbufs) & (pipe->buffers - 1);
- struct pipe_buffer *buf = pipe->bufs + newbuf;
-
- buf->page = bufs[page_nr].page;
- buf->offset = bufs[page_nr].offset;
- buf->len = bufs[page_nr].len;
+ for (ret = total = 0; page_nr < cs.nr_segs; total += ret) {
/*
* Need to be careful about this. Having buf->ops in module
* code can Oops if the buffer persists after module unload.
*/
- buf->ops = &nosteal_pipe_buf_ops;
-
- pipe->nrbufs++;
- page_nr++;
- ret += buf->len;
-
- if (pipe->files)
- do_wakeup = 1;
- }
-
-out_unlock:
- pipe_unlock(pipe);
-
- if (do_wakeup) {
- smp_mb();
- if (waitqueue_active(&pipe->wait))
- wake_up_interruptible(&pipe->wait);
- kill_fasync(&pipe->fasync_readers, SIGIO, POLL_IN);
+ bufs[page_nr].ops = &nosteal_pipe_buf_ops;
+ ret = add_to_pipe(pipe, &bufs[page_nr++]);
+ if (unlikely(ret < 0))
+ break;
}
-
+ if (total)
+ ret = total;
out:
for (; page_nr < cs.nr_segs; page_nr++)
put_page(bufs[page_nr].page);
pipe->curbuf = (pipe->curbuf + 1) & (pipe->buffers - 1);
pipe->nrbufs--;
} else {
- ibuf->ops->get(pipe, ibuf);
+ pipe_buf_get(pipe, ibuf);
*obuf = *ibuf;
obuf->flags &= ~PIPE_BUF_FLAG_GIFT;
obuf->len = rem;
ret = fuse_dev_do_write(fud, &cs, len);
- for (idx = 0; idx < nbuf; idx++) {
- struct pipe_buffer *buf = &bufs[idx];
- buf->ops->release(pipe, buf);
- }
+ for (idx = 0; idx < nbuf; idx++)
+ pipe_buf_release(pipe, &bufs[idx]);
+
out:
kfree(bufs);
return ret;
return ret;
}
-static ssize_t gfs2_file_splice_read(struct file *in, loff_t *ppos,
- struct pipe_inode_info *pipe, size_t len,
- unsigned int flags)
-{
- struct inode *inode = in->f_mapping->host;
- struct gfs2_inode *ip = GFS2_I(inode);
- struct gfs2_holder gh;
- int ret;
-
- inode_lock(inode);
-
- ret = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &gh);
- if (ret) {
- inode_unlock(inode);
- return ret;
- }
-
- gfs2_glock_dq_uninit(&gh);
- inode_unlock(inode);
-
- return generic_file_splice_read(in, ppos, pipe, len, flags);
-}
-
-
static ssize_t gfs2_file_splice_write(struct pipe_inode_info *pipe,
struct file *out, loff_t *ppos,
size_t len, unsigned int flags)
.fsync = gfs2_fsync,
.lock = gfs2_lock,
.flock = gfs2_flock,
- .splice_read = gfs2_file_splice_read,
+ .splice_read = generic_file_splice_read,
.splice_write = gfs2_file_splice_write,
.setlease = simple_nosetlease,
.fallocate = gfs2_fallocate,
.open = gfs2_open,
.release = gfs2_release,
.fsync = gfs2_fsync,
- .splice_read = gfs2_file_splice_read,
+ .splice_read = generic_file_splice_read,
.splice_write = gfs2_file_splice_write,
.setlease = generic_setlease,
.fallocate = gfs2_fallocate,
}
EXPORT_SYMBOL_GPL(nfs_file_read);
-ssize_t
-nfs_file_splice_read(struct file *filp, loff_t *ppos,
- struct pipe_inode_info *pipe, size_t count,
- unsigned int flags)
-{
- struct inode *inode = file_inode(filp);
- ssize_t res;
-
- dprintk("NFS: splice_read(%pD2, %lu@%Lu)\n",
- filp, (unsigned long) count, (unsigned long long) *ppos);
-
- nfs_start_io_read(inode);
- res = nfs_revalidate_mapping(inode, filp->f_mapping);
- if (!res) {
- res = generic_file_splice_read(filp, ppos, pipe, count, flags);
- if (res > 0)
- nfs_add_stats(inode, NFSIOS_NORMALREADBYTES, res);
- }
- nfs_end_io_read(inode);
- return res;
-}
-EXPORT_SYMBOL_GPL(nfs_file_splice_read);
-
int
nfs_file_mmap(struct file * file, struct vm_area_struct * vma)
{
.fsync = nfs_file_fsync,
.lock = nfs_lock,
.flock = nfs_flock,
- .splice_read = nfs_file_splice_read,
+ .splice_read = generic_file_splice_read,
.splice_write = iter_file_splice_write,
.check_flags = nfs_check_flags,
.setlease = simple_nosetlease,
int nfs_file_fsync(struct file *file, loff_t start, loff_t end, int datasync);
loff_t nfs_file_llseek(struct file *, loff_t, int);
ssize_t nfs_file_read(struct kiocb *, struct iov_iter *);
-ssize_t nfs_file_splice_read(struct file *, loff_t *, struct pipe_inode_info *,
- size_t, unsigned int);
int nfs_file_mmap(struct file *, struct vm_area_struct *);
ssize_t nfs_file_write(struct kiocb *, struct iov_iter *);
int nfs_file_release(struct inode *, struct file *);
.fsync = nfs_file_fsync,
.lock = nfs_lock,
.flock = nfs_flock,
- .splice_read = nfs_file_splice_read,
+ .splice_read = generic_file_splice_read,
.splice_write = iter_file_splice_write,
.check_flags = nfs_check_flags,
.setlease = simple_nosetlease,
return ret;
}
-static ssize_t ocfs2_file_splice_read(struct file *in,
- loff_t *ppos,
- struct pipe_inode_info *pipe,
- size_t len,
- unsigned int flags)
-{
- int ret = 0, lock_level = 0;
- struct inode *inode = file_inode(in);
-
- trace_ocfs2_file_splice_read(inode, in, in->f_path.dentry,
- (unsigned long long)OCFS2_I(inode)->ip_blkno,
- in->f_path.dentry->d_name.len,
- in->f_path.dentry->d_name.name, len);
-
- /*
- * See the comment in ocfs2_file_read_iter()
- */
- ret = ocfs2_inode_lock_atime(inode, in->f_path.mnt, &lock_level);
- if (ret < 0) {
- mlog_errno(ret);
- goto bail;
- }
- ocfs2_inode_unlock(inode, lock_level);
-
- ret = generic_file_splice_read(in, ppos, pipe, len, flags);
-
-bail:
- return ret;
-}
-
static ssize_t ocfs2_file_read_iter(struct kiocb *iocb,
struct iov_iter *to)
{
#endif
.lock = ocfs2_lock,
.flock = ocfs2_flock,
- .splice_read = ocfs2_file_splice_read,
+ .splice_read = generic_file_splice_read,
.splice_write = iter_file_splice_write,
.fallocate = ocfs2_fallocate,
};
.compat_ioctl = ocfs2_compat_ioctl,
#endif
.flock = ocfs2_flock,
- .splice_read = ocfs2_file_splice_read,
+ .splice_read = generic_file_splice_read,
.splice_write = iter_file_splice_write,
.fallocate = ocfs2_fallocate,
};
DEFINE_OCFS2_FILE_OPS(ocfs2_file_splice_write);
-DEFINE_OCFS2_FILE_OPS(ocfs2_file_splice_read);
-
DEFINE_OCFS2_FILE_OPS(ocfs2_file_aio_read);
DEFINE_OCFS2_ULL_ULL_ULL_EVENT(ocfs2_truncate_file);
if (bufs) {
int curbuf = pipe->curbuf;
struct pipe_buffer *buf = pipe->bufs + curbuf;
- const struct pipe_buf_operations *ops = buf->ops;
size_t chars = buf->len;
size_t written;
int error;
if (chars > total_len)
chars = total_len;
- error = ops->confirm(pipe, buf);
+ error = pipe_buf_confirm(pipe, buf);
if (error) {
if (!ret)
ret = error;
}
if (!buf->len) {
- buf->ops = NULL;
- ops->release(pipe, buf);
+ pipe_buf_release(pipe, buf);
curbuf = (curbuf + 1) & (pipe->buffers - 1);
pipe->curbuf = curbuf;
pipe->nrbufs = --bufs;
int lastbuf = (pipe->curbuf + pipe->nrbufs - 1) &
(pipe->buffers - 1);
struct pipe_buffer *buf = pipe->bufs + lastbuf;
- const struct pipe_buf_operations *ops = buf->ops;
int offset = buf->offset + buf->len;
- if (ops->can_merge && offset + chars <= PAGE_SIZE) {
- ret = ops->confirm(pipe, buf);
+ if (buf->ops->can_merge && offset + chars <= PAGE_SIZE) {
+ ret = pipe_buf_confirm(pipe, buf);
if (ret)
goto out;
for (i = 0; i < pipe->buffers; i++) {
struct pipe_buffer *buf = pipe->bufs + i;
if (buf->ops)
- buf->ops->release(pipe, buf);
+ pipe_buf_release(pipe, buf);
}
if (pipe->tmp_page)
__free_page(pipe->tmp_page);
struct splice_pipe_desc *spd)
{
unsigned int spd_pages = spd->nr_pages;
- int ret, do_wakeup, page_nr;
+ int ret = 0, page_nr = 0;
if (!spd_pages)
return 0;
- ret = 0;
- do_wakeup = 0;
- page_nr = 0;
-
- pipe_lock(pipe);
-
- for (;;) {
- if (!pipe->readers) {
- send_sig(SIGPIPE, current, 0);
- if (!ret)
- ret = -EPIPE;
- break;
- }
-
- if (pipe->nrbufs < pipe->buffers) {
- int newbuf = (pipe->curbuf + pipe->nrbufs) & (pipe->buffers - 1);
- struct pipe_buffer *buf = pipe->bufs + newbuf;
-
- buf->page = spd->pages[page_nr];
- buf->offset = spd->partial[page_nr].offset;
- buf->len = spd->partial[page_nr].len;
- buf->private = spd->partial[page_nr].private;
- buf->ops = spd->ops;
- if (spd->flags & SPLICE_F_GIFT)
- buf->flags |= PIPE_BUF_FLAG_GIFT;
-
- pipe->nrbufs++;
- page_nr++;
- ret += buf->len;
-
- if (pipe->files)
- do_wakeup = 1;
+ if (unlikely(!pipe->readers)) {
+ send_sig(SIGPIPE, current, 0);
+ ret = -EPIPE;
+ goto out;
+ }
- if (!--spd->nr_pages)
- break;
- if (pipe->nrbufs < pipe->buffers)
- continue;
+ while (pipe->nrbufs < pipe->buffers) {
+ int newbuf = (pipe->curbuf + pipe->nrbufs) & (pipe->buffers - 1);
+ struct pipe_buffer *buf = pipe->bufs + newbuf;
- break;
- }
+ buf->page = spd->pages[page_nr];
+ buf->offset = spd->partial[page_nr].offset;
+ buf->len = spd->partial[page_nr].len;
+ buf->private = spd->partial[page_nr].private;
+ buf->ops = spd->ops;
- if (spd->flags & SPLICE_F_NONBLOCK) {
- if (!ret)
- ret = -EAGAIN;
- break;
- }
+ pipe->nrbufs++;
+ page_nr++;
+ ret += buf->len;
- if (signal_pending(current)) {
- if (!ret)
- ret = -ERESTARTSYS;
+ if (!--spd->nr_pages)
break;
- }
-
- if (do_wakeup) {
- smp_mb();
- if (waitqueue_active(&pipe->wait))
- wake_up_interruptible_sync(&pipe->wait);
- kill_fasync(&pipe->fasync_readers, SIGIO, POLL_IN);
- do_wakeup = 0;
- }
-
- pipe->waiting_writers++;
- pipe_wait(pipe);
- pipe->waiting_writers--;
}
- pipe_unlock(pipe);
-
- if (do_wakeup)
- wakeup_pipe_readers(pipe);
+ if (!ret)
+ ret = -EAGAIN;
+out:
while (page_nr < spd_pages)
spd->spd_release(spd, page_nr++);
}
EXPORT_SYMBOL_GPL(splice_to_pipe);
+ssize_t add_to_pipe(struct pipe_inode_info *pipe, struct pipe_buffer *buf)
+{
+ int ret;
+
+ if (unlikely(!pipe->readers)) {
+ send_sig(SIGPIPE, current, 0);
+ ret = -EPIPE;
+ } else if (pipe->nrbufs == pipe->buffers) {
+ ret = -EAGAIN;
+ } else {
+ int newbuf = (pipe->curbuf + pipe->nrbufs) & (pipe->buffers - 1);
+ pipe->bufs[newbuf] = *buf;
+ pipe->nrbufs++;
+ return buf->len;
+ }
+ pipe_buf_release(pipe, buf);
+ return ret;
+}
+EXPORT_SYMBOL(add_to_pipe);
+
void spd_release_page(struct splice_pipe_desc *spd, unsigned int i)
{
put_page(spd->pages[i]);
kfree(spd->partial);
}
-static int
-__generic_file_splice_read(struct file *in, loff_t *ppos,
- struct pipe_inode_info *pipe, size_t len,
- unsigned int flags)
-{
- struct address_space *mapping = in->f_mapping;
- unsigned int loff, nr_pages, req_pages;
- struct page *pages[PIPE_DEF_BUFFERS];
- struct partial_page partial[PIPE_DEF_BUFFERS];
- struct page *page;
- pgoff_t index, end_index;
- loff_t isize;
- int error, page_nr;
- struct splice_pipe_desc spd = {
- .pages = pages,
- .partial = partial,
- .nr_pages_max = PIPE_DEF_BUFFERS,
- .flags = flags,
- .ops = &page_cache_pipe_buf_ops,
- .spd_release = spd_release_page,
- };
-
- if (splice_grow_spd(pipe, &spd))
- return -ENOMEM;
-
- index = *ppos >> PAGE_SHIFT;
- loff = *ppos & ~PAGE_MASK;
- req_pages = (len + loff + PAGE_SIZE - 1) >> PAGE_SHIFT;
- nr_pages = min(req_pages, spd.nr_pages_max);
-
- /*
- * Lookup the (hopefully) full range of pages we need.
- */
- spd.nr_pages = find_get_pages_contig(mapping, index, nr_pages, spd.pages);
- index += spd.nr_pages;
-
- /*
- * If find_get_pages_contig() returned fewer pages than we needed,
- * readahead/allocate the rest and fill in the holes.
- */
- if (spd.nr_pages < nr_pages)
- page_cache_sync_readahead(mapping, &in->f_ra, in,
- index, req_pages - spd.nr_pages);
-
- error = 0;
- while (spd.nr_pages < nr_pages) {
- /*
- * Page could be there, find_get_pages_contig() breaks on
- * the first hole.
- */
- page = find_get_page(mapping, index);
- if (!page) {
- /*
- * page didn't exist, allocate one.
- */
- page = page_cache_alloc_cold(mapping);
- if (!page)
- break;
-
- error = add_to_page_cache_lru(page, mapping, index,
- mapping_gfp_constraint(mapping, GFP_KERNEL));
- if (unlikely(error)) {
- put_page(page);
- if (error == -EEXIST)
- continue;
- break;
- }
- /*
- * add_to_page_cache() locks the page, unlock it
- * to avoid convoluting the logic below even more.
- */
- unlock_page(page);
- }
-
- spd.pages[spd.nr_pages++] = page;
- index++;
- }
-
- /*
- * Now loop over the map and see if we need to start IO on any
- * pages, fill in the partial map, etc.
- */
- index = *ppos >> PAGE_SHIFT;
- nr_pages = spd.nr_pages;
- spd.nr_pages = 0;
- for (page_nr = 0; page_nr < nr_pages; page_nr++) {
- unsigned int this_len;
-
- if (!len)
- break;
-
- /*
- * this_len is the max we'll use from this page
- */
- this_len = min_t(unsigned long, len, PAGE_SIZE - loff);
- page = spd.pages[page_nr];
-
- if (PageReadahead(page))
- page_cache_async_readahead(mapping, &in->f_ra, in,
- page, index, req_pages - page_nr);
-
- /*
- * If the page isn't uptodate, we may need to start io on it
- */
- if (!PageUptodate(page)) {
- lock_page(page);
-
- /*
- * Page was truncated, or invalidated by the
- * filesystem. Redo the find/create, but this time the
- * page is kept locked, so there's no chance of another
- * race with truncate/invalidate.
- */
- if (!page->mapping) {
- unlock_page(page);
-retry_lookup:
- page = find_or_create_page(mapping, index,
- mapping_gfp_mask(mapping));
-
- if (!page) {
- error = -ENOMEM;
- break;
- }
- put_page(spd.pages[page_nr]);
- spd.pages[page_nr] = page;
- }
- /*
- * page was already under io and is now done, great
- */
- if (PageUptodate(page)) {
- unlock_page(page);
- goto fill_it;
- }
-
- /*
- * need to read in the page
- */
- error = mapping->a_ops->readpage(in, page);
- if (unlikely(error)) {
- /*
- * Re-lookup the page
- */
- if (error == AOP_TRUNCATED_PAGE)
- goto retry_lookup;
-
- break;
- }
- }
-fill_it:
- /*
- * i_size must be checked after PageUptodate.
- */
- isize = i_size_read(mapping->host);
- end_index = (isize - 1) >> PAGE_SHIFT;
- if (unlikely(!isize || index > end_index))
- break;
-
- /*
- * if this is the last page, see if we need to shrink
- * the length and stop
- */
- if (end_index == index) {
- unsigned int plen;
-
- /*
- * max good bytes in this page
- */
- plen = ((isize - 1) & ~PAGE_MASK) + 1;
- if (plen <= loff)
- break;
-
- /*
- * force quit after adding this page
- */
- this_len = min(this_len, plen - loff);
- len = this_len;
- }
-
- spd.partial[page_nr].offset = loff;
- spd.partial[page_nr].len = this_len;
- len -= this_len;
- loff = 0;
- spd.nr_pages++;
- index++;
- }
-
- /*
- * Release any pages at the end, if we quit early. 'page_nr' is how far
- * we got, 'nr_pages' is how many pages are in the map.
- */
- while (page_nr < nr_pages)
- put_page(spd.pages[page_nr++]);
- in->f_ra.prev_pos = (loff_t)index << PAGE_SHIFT;
-
- if (spd.nr_pages)
- error = splice_to_pipe(pipe, &spd);
-
- splice_shrink_spd(&spd);
- return error;
-}
-
/**
* generic_file_splice_read - splice data from file to a pipe
* @in: file to splice from
*
* Description:
* Will read pages from given file and fill them into a pipe. Can be
- * used as long as the address_space operations for the source implements
- * a readpage() hook.
+ * used as long as it has more or less sane ->read_iter().
*
*/
ssize_t generic_file_splice_read(struct file *in, loff_t *ppos,
struct pipe_inode_info *pipe, size_t len,
unsigned int flags)
{
- loff_t isize, left;
- int ret;
-
- if (IS_DAX(in->f_mapping->host))
- return default_file_splice_read(in, ppos, pipe, len, flags);
+ struct iov_iter to;
+ struct kiocb kiocb;
+ loff_t isize;
+ int idx, ret;
isize = i_size_read(in->f_mapping->host);
if (unlikely(*ppos >= isize))
return 0;
- left = isize - *ppos;
- if (unlikely(left < len))
- len = left;
-
- ret = __generic_file_splice_read(in, ppos, pipe, len, flags);
+ iov_iter_pipe(&to, ITER_PIPE | READ, pipe, len);
+ idx = to.idx;
+ init_sync_kiocb(&kiocb, in);
+ kiocb.ki_pos = *ppos;
+ ret = in->f_op->read_iter(&kiocb, &to);
if (ret > 0) {
- *ppos += ret;
+ *ppos = kiocb.ki_pos;
file_accessed(in);
+ } else if (ret < 0) {
+ if (WARN_ON(to.idx != idx || to.iov_offset)) {
+ /*
+ * a bogus ->read_iter() has copied something and still
+ * returned an error instead of a short read.
+ */
+ to.idx = idx;
+ to.iov_offset = 0;
+ iov_iter_advance(&to, 0); /* to free what was emitted */
+ }
+ /*
+ * callers of ->splice_read() expect -EAGAIN on
+ * "can't put anything in there", rather than -EFAULT.
+ */
+ if (ret == -EFAULT)
+ ret = -EAGAIN;
}
return ret;
}
EXPORT_SYMBOL(generic_file_splice_read);
-static const struct pipe_buf_operations default_pipe_buf_ops = {
+const struct pipe_buf_operations default_pipe_buf_ops = {
.can_merge = 0,
.confirm = generic_pipe_buf_confirm,
.release = generic_pipe_buf_release,
};
EXPORT_SYMBOL(nosteal_pipe_buf_ops);
-static ssize_t kernel_readv(struct file *file, const struct iovec *vec,
+static ssize_t kernel_readv(struct file *file, const struct kvec *vec,
unsigned long vlen, loff_t offset)
{
mm_segment_t old_fs;
}
EXPORT_SYMBOL(kernel_write);
-ssize_t default_file_splice_read(struct file *in, loff_t *ppos,
+static ssize_t default_file_splice_read(struct file *in, loff_t *ppos,
struct pipe_inode_info *pipe, size_t len,
unsigned int flags)
{
+ struct kvec *vec, __vec[PIPE_DEF_BUFFERS];
+ struct iov_iter to;
+ struct page **pages;
unsigned int nr_pages;
- unsigned int nr_freed;
- size_t offset;
- struct page *pages[PIPE_DEF_BUFFERS];
- struct partial_page partial[PIPE_DEF_BUFFERS];
- struct iovec *vec, __vec[PIPE_DEF_BUFFERS];
+ size_t offset, dummy, copied = 0;
ssize_t res;
- size_t this_len;
- int error;
int i;
- struct splice_pipe_desc spd = {
- .pages = pages,
- .partial = partial,
- .nr_pages_max = PIPE_DEF_BUFFERS,
- .flags = flags,
- .ops = &default_pipe_buf_ops,
- .spd_release = spd_release_page,
- };
- if (splice_grow_spd(pipe, &spd))
+ if (pipe->nrbufs == pipe->buffers)
+ return -EAGAIN;
+
+ /*
+ * Try to keep page boundaries matching to source pagecache ones -
+ * it probably won't be much help, but...
+ */
+ offset = *ppos & ~PAGE_MASK;
+
+ iov_iter_pipe(&to, ITER_PIPE | READ, pipe, len + offset);
+
+ res = iov_iter_get_pages_alloc(&to, &pages, len + offset, &dummy);
+ if (res <= 0)
return -ENOMEM;
- res = -ENOMEM;
+ nr_pages = res / PAGE_SIZE;
+
vec = __vec;
- if (spd.nr_pages_max > PIPE_DEF_BUFFERS) {
- vec = kmalloc(spd.nr_pages_max * sizeof(struct iovec), GFP_KERNEL);
- if (!vec)
- goto shrink_ret;
+ if (nr_pages > PIPE_DEF_BUFFERS) {
+ vec = kmalloc(nr_pages * sizeof(struct kvec), GFP_KERNEL);
+ if (unlikely(!vec)) {
+ res = -ENOMEM;
+ goto out;
+ }
}
- offset = *ppos & ~PAGE_MASK;
- nr_pages = (len + offset + PAGE_SIZE - 1) >> PAGE_SHIFT;
-
- for (i = 0; i < nr_pages && i < spd.nr_pages_max && len; i++) {
- struct page *page;
+ pipe->bufs[to.idx].offset = offset;
+ pipe->bufs[to.idx].len -= offset;
- page = alloc_page(GFP_USER);
- error = -ENOMEM;
- if (!page)
- goto err;
-
- this_len = min_t(size_t, len, PAGE_SIZE - offset);
- vec[i].iov_base = (void __user *) page_address(page);
+ for (i = 0; i < nr_pages; i++) {
+ size_t this_len = min_t(size_t, len, PAGE_SIZE - offset);
+ vec[i].iov_base = page_address(pages[i]) + offset;
vec[i].iov_len = this_len;
- spd.pages[i] = page;
- spd.nr_pages++;
len -= this_len;
offset = 0;
}
- res = kernel_readv(in, vec, spd.nr_pages, *ppos);
- if (res < 0) {
- error = res;
- goto err;
- }
-
- error = 0;
- if (!res)
- goto err;
-
- nr_freed = 0;
- for (i = 0; i < spd.nr_pages; i++) {
- this_len = min_t(size_t, vec[i].iov_len, res);
- spd.partial[i].offset = 0;
- spd.partial[i].len = this_len;
- if (!this_len) {
- __free_page(spd.pages[i]);
- spd.pages[i] = NULL;
- nr_freed++;
- }
- res -= this_len;
- }
- spd.nr_pages -= nr_freed;
-
- res = splice_to_pipe(pipe, &spd);
- if (res > 0)
+ res = kernel_readv(in, vec, nr_pages, *ppos);
+ if (res > 0) {
+ copied = res;
*ppos += res;
+ }
-shrink_ret:
if (vec != __vec)
kfree(vec);
- splice_shrink_spd(&spd);
+out:
+ for (i = 0; i < nr_pages; i++)
+ put_page(pages[i]);
+ kvfree(pages);
+ iov_iter_advance(&to, copied); /* truncates and discards */
return res;
-
-err:
- for (i = 0; i < spd.nr_pages; i++)
- __free_page(spd.pages[i]);
-
- res = error;
- goto shrink_ret;
}
-EXPORT_SYMBOL(default_file_splice_read);
/*
* Send 'sd->len' bytes to socket from 'sd->file' at position 'sd->pos'
while (pipe->nrbufs) {
struct pipe_buffer *buf = pipe->bufs + pipe->curbuf;
- const struct pipe_buf_operations *ops = buf->ops;
sd->len = buf->len;
if (sd->len > sd->total_len)
sd->len = sd->total_len;
- ret = buf->ops->confirm(pipe, buf);
+ ret = pipe_buf_confirm(pipe, buf);
if (unlikely(ret)) {
if (ret == -ENODATA)
ret = 0;
sd->total_len -= ret;
if (!buf->len) {
- buf->ops = NULL;
- ops->release(pipe, buf);
+ pipe_buf_release(pipe, buf);
pipe->curbuf = (pipe->curbuf + 1) & (pipe->buffers - 1);
pipe->nrbufs--;
if (pipe->files)
if (idx == pipe->buffers - 1)
idx = -1;
- ret = buf->ops->confirm(pipe, buf);
+ ret = pipe_buf_confirm(pipe, buf);
if (unlikely(ret)) {
if (ret == -ENODATA)
ret = 0;
while (ret) {
struct pipe_buffer *buf = pipe->bufs + pipe->curbuf;
if (ret >= buf->len) {
- const struct pipe_buf_operations *ops = buf->ops;
ret -= buf->len;
buf->len = 0;
- buf->ops = NULL;
- ops->release(pipe, buf);
+ pipe_buf_release(pipe, buf);
pipe->curbuf = (pipe->curbuf + 1) & (pipe->buffers - 1);
pipe->nrbufs--;
if (pipe->files)
for (i = 0; i < pipe->buffers; i++) {
struct pipe_buffer *buf = pipe->bufs + i;
- if (buf->ops) {
- buf->ops->release(pipe, buf);
- buf->ops = NULL;
- }
+ if (buf->ops)
+ pipe_buf_release(pipe, buf);
}
if (!bytes)
}
EXPORT_SYMBOL(do_splice_direct);
+static int wait_for_space(struct pipe_inode_info *pipe, unsigned flags)
+{
+ while (pipe->nrbufs == pipe->buffers) {
+ if (flags & SPLICE_F_NONBLOCK)
+ return -EAGAIN;
+ if (signal_pending(current))
+ return -ERESTARTSYS;
+ pipe->waiting_writers++;
+ pipe_wait(pipe);
+ pipe->waiting_writers--;
+ }
+ return 0;
+}
+
static int splice_pipe_to_pipe(struct pipe_inode_info *ipipe,
struct pipe_inode_info *opipe,
size_t len, unsigned int flags);
offset = in->f_pos;
}
- ret = do_splice_to(in, &offset, opipe, len, flags);
-
+ pipe_lock(opipe);
+ ret = wait_for_space(opipe, flags);
+ if (!ret)
+ ret = do_splice_to(in, &offset, opipe, len, flags);
+ pipe_unlock(opipe);
+ if (ret > 0)
+ wakeup_pipe_readers(opipe);
if (!off_in)
in->f_pos = offset;
else if (copy_to_user(off_in, &offset, sizeof(loff_t)))
return -EINVAL;
}
-/*
- * Map an iov into an array of pages and offset/length tupples. With the
- * partial_page structure, we can map several non-contiguous ranges into
- * our ones pages[] map instead of splitting that operation into pieces.
- * Could easily be exported as a generic helper for other users, in which
- * case one would probably want to add a 'max_nr_pages' parameter as well.
- */
-static int get_iovec_page_array(const struct iovec __user *iov,
- unsigned int nr_vecs, struct page **pages,
- struct partial_page *partial, bool aligned,
- unsigned int pipe_buffers)
+static int iter_to_pipe(struct iov_iter *from,
+ struct pipe_inode_info *pipe,
+ unsigned flags)
{
- int buffers = 0, error = 0;
-
- while (nr_vecs) {
- unsigned long off, npages;
- struct iovec entry;
- void __user *base;
- size_t len;
- int i;
-
- error = -EFAULT;
- if (copy_from_user(&entry, iov, sizeof(entry)))
- break;
-
- base = entry.iov_base;
- len = entry.iov_len;
-
- /*
- * Sanity check this iovec. 0 read succeeds.
- */
- error = 0;
- if (unlikely(!len))
- break;
- error = -EFAULT;
- if (!access_ok(VERIFY_READ, base, len))
- break;
-
- /*
- * Get this base offset and number of pages, then map
- * in the user pages.
- */
- off = (unsigned long) base & ~PAGE_MASK;
-
- /*
- * If asked for alignment, the offset must be zero and the
- * length a multiple of the PAGE_SIZE.
- */
- error = -EINVAL;
- if (aligned && (off || len & ~PAGE_MASK))
- break;
-
- npages = (off + len + PAGE_SIZE - 1) >> PAGE_SHIFT;
- if (npages > pipe_buffers - buffers)
- npages = pipe_buffers - buffers;
-
- error = get_user_pages_fast((unsigned long)base, npages,
- 0, &pages[buffers]);
-
- if (unlikely(error <= 0))
+ struct pipe_buffer buf = {
+ .ops = &user_page_pipe_buf_ops,
+ .flags = flags
+ };
+ size_t total = 0;
+ int ret = 0;
+ bool failed = false;
+
+ while (iov_iter_count(from) && !failed) {
+ struct page *pages[16];
+ ssize_t copied;
+ size_t start;
+ int n;
+
+ copied = iov_iter_get_pages(from, pages, ~0UL, 16, &start);
+ if (copied <= 0) {
+ ret = copied;
break;
-
- /*
- * Fill this contiguous range into the partial page map.
- */
- for (i = 0; i < error; i++) {
- const int plen = min_t(size_t, len, PAGE_SIZE - off);
-
- partial[buffers].offset = off;
- partial[buffers].len = plen;
-
- off = 0;
- len -= plen;
- buffers++;
}
- /*
- * We didn't complete this iov, stop here since it probably
- * means we have to move some of this into a pipe to
- * be able to continue.
- */
- if (len)
- break;
-
- /*
- * Don't continue if we mapped fewer pages than we asked for,
- * or if we mapped the max number of pages that we have
- * room for.
- */
- if (error < npages || buffers == pipe_buffers)
- break;
-
- nr_vecs--;
- iov++;
+ for (n = 0; copied; n++, start = 0) {
+ int size = min_t(int, copied, PAGE_SIZE - start);
+ if (!failed) {
+ buf.page = pages[n];
+ buf.offset = start;
+ buf.len = size;
+ ret = add_to_pipe(pipe, &buf);
+ if (unlikely(ret < 0)) {
+ failed = true;
+ } else {
+ iov_iter_advance(from, ret);
+ total += ret;
+ }
+ } else {
+ put_page(pages[n]);
+ }
+ copied -= size;
+ }
}
-
- if (buffers)
- return buffers;
-
- return error;
+ return total ? total : ret;
}
static int pipe_to_user(struct pipe_inode_info *pipe, struct pipe_buffer *buf,
* as splice-from-memory, where the regular splice is splice-from-file (or
* to file). In both cases the output is a pipe, naturally.
*/
-static long vmsplice_to_pipe(struct file *file, const struct iovec __user *iov,
+static long vmsplice_to_pipe(struct file *file, const struct iovec __user *uiov,
unsigned long nr_segs, unsigned int flags)
{
struct pipe_inode_info *pipe;
- struct page *pages[PIPE_DEF_BUFFERS];
- struct partial_page partial[PIPE_DEF_BUFFERS];
- struct splice_pipe_desc spd = {
- .pages = pages,
- .partial = partial,
- .nr_pages_max = PIPE_DEF_BUFFERS,
- .flags = flags,
- .ops = &user_page_pipe_buf_ops,
- .spd_release = spd_release_page,
- };
+ struct iovec iovstack[UIO_FASTIOV];
+ struct iovec *iov = iovstack;
+ struct iov_iter from;
long ret;
+ unsigned buf_flag = 0;
+
+ if (flags & SPLICE_F_GIFT)
+ buf_flag = PIPE_BUF_FLAG_GIFT;
pipe = get_pipe_info(file);
if (!pipe)
return -EBADF;
- if (splice_grow_spd(pipe, &spd))
- return -ENOMEM;
-
- spd.nr_pages = get_iovec_page_array(iov, nr_segs, spd.pages,
- spd.partial, false,
- spd.nr_pages_max);
- if (spd.nr_pages <= 0)
- ret = spd.nr_pages;
- else
- ret = splice_to_pipe(pipe, &spd);
+ ret = import_iovec(WRITE, uiov, nr_segs,
+ ARRAY_SIZE(iovstack), &iov, &from);
+ if (ret < 0)
+ return ret;
- splice_shrink_spd(&spd);
+ pipe_lock(pipe);
+ ret = wait_for_space(pipe, flags);
+ if (!ret)
+ ret = iter_to_pipe(&from, pipe, buf_flag);
+ pipe_unlock(pipe);
+ if (ret > 0)
+ wakeup_pipe_readers(pipe);
+ kfree(iov);
return ret;
}
* Get a reference to this pipe buffer,
* so we can copy the contents over.
*/
- ibuf->ops->get(ipipe, ibuf);
+ pipe_buf_get(ipipe, ibuf);
*obuf = *ibuf;
/*
* Get a reference to this pipe buffer,
* so we can copy the contents over.
*/
- ibuf->ops->get(ipipe, ibuf);
+ pipe_buf_get(ipipe, ibuf);
obuf = opipe->bufs + nbuf;
*obuf = *ibuf;
return ret;
}
-STATIC ssize_t
-xfs_file_splice_read(
- struct file *infilp,
- loff_t *ppos,
- struct pipe_inode_info *pipe,
- size_t count,
- unsigned int flags)
-{
- struct xfs_inode *ip = XFS_I(infilp->f_mapping->host);
- ssize_t ret;
-
- XFS_STATS_INC(ip->i_mount, xs_read_calls);
-
- if (XFS_FORCED_SHUTDOWN(ip->i_mount))
- return -EIO;
-
- trace_xfs_file_splice_read(ip, count, *ppos);
-
- /*
- * DAX inodes cannot ues the page cache for splice, so we have to push
- * them through the VFS IO path. This means it goes through
- * ->read_iter, which for us takes the XFS_IOLOCK_SHARED. Hence we
- * cannot lock the splice operation at this level for DAX inodes.
- */
- if (IS_DAX(VFS_I(ip))) {
- ret = default_file_splice_read(infilp, ppos, pipe, count,
- flags);
- goto out;
- }
-
- xfs_rw_ilock(ip, XFS_IOLOCK_SHARED);
- ret = generic_file_splice_read(infilp, ppos, pipe, count, flags);
- xfs_rw_iunlock(ip, XFS_IOLOCK_SHARED);
-out:
- if (ret > 0)
- XFS_STATS_ADD(ip->i_mount, xs_read_bytes, ret);
- return ret;
-}
-
/*
* Zero any on disk space between the current EOF and the new, larger EOF.
*
.llseek = xfs_file_llseek,
.read_iter = xfs_file_read_iter,
.write_iter = xfs_file_write_iter,
- .splice_read = xfs_file_splice_read,
+ .splice_read = generic_file_splice_read,
.splice_write = iter_file_splice_write,
.unlocked_ioctl = xfs_file_ioctl,
#ifdef CONFIG_COMPAT
DEFINE_RW_EVENT(xfs_file_buffered_write);
DEFINE_RW_EVENT(xfs_file_direct_write);
DEFINE_RW_EVENT(xfs_file_dax_write);
-DEFINE_RW_EVENT(xfs_file_splice_read);
DECLARE_EVENT_CLASS(xfs_page_class,
TP_PROTO(struct inode *inode, struct page *page, unsigned long off,
/* fs/splice.c */
extern ssize_t generic_file_splice_read(struct file *, loff_t *,
struct pipe_inode_info *, size_t, unsigned int);
-extern ssize_t default_file_splice_read(struct file *, loff_t *,
- struct pipe_inode_info *, size_t, unsigned int);
extern ssize_t iter_file_splice_write(struct pipe_inode_info *,
struct file *, loff_t *, size_t, unsigned int);
extern ssize_t generic_splice_sendpage(struct pipe_inode_info *pipe,
*
* ->confirm()
* ->steal()
- * ...
- * ->map()
- * ...
- * ->unmap()
*
- * That is, ->map() must be called on a confirmed buffer,
- * same goes for ->steal(). See below for the meaning of each
- * operation. Also see kerneldoc in fs/pipe.c for the pipe
- * and generic variants of these hooks.
+ * That is, ->steal() must be called on a confirmed buffer.
+ * See below for the meaning of each operation. Also see kerneldoc
+ * in fs/pipe.c for the pipe and generic variants of these hooks.
*/
struct pipe_buf_operations {
/*
void (*get)(struct pipe_inode_info *, struct pipe_buffer *);
};
+/**
+ * pipe_buf_get - get a reference to a pipe_buffer
+ * @pipe: the pipe that the buffer belongs to
+ * @buf: the buffer to get a reference to
+ */
+static inline void pipe_buf_get(struct pipe_inode_info *pipe,
+ struct pipe_buffer *buf)
+{
+ buf->ops->get(pipe, buf);
+}
+
+/**
+ * pipe_buf_release - put a reference to a pipe_buffer
+ * @pipe: the pipe that the buffer belongs to
+ * @buf: the buffer to put a reference to
+ */
+static inline void pipe_buf_release(struct pipe_inode_info *pipe,
+ struct pipe_buffer *buf)
+{
+ const struct pipe_buf_operations *ops = buf->ops;
+
+ buf->ops = NULL;
+ ops->release(pipe, buf);
+}
+
+/**
+ * pipe_buf_confirm - verify contents of the pipe buffer
+ * @pipe: the pipe that the buffer belongs to
+ * @buf: the buffer to confirm
+ */
+static inline int pipe_buf_confirm(struct pipe_inode_info *pipe,
+ struct pipe_buffer *buf)
+{
+ return buf->ops->confirm(pipe, buf);
+}
+
+/**
+ * pipe_buf_steal - attempt to take ownership of a pipe_buffer
+ * @pipe: the pipe that the buffer belongs to
+ * @buf: the buffer to attempt to steal
+ */
+static inline int pipe_buf_steal(struct pipe_inode_info *pipe,
+ struct pipe_buffer *buf)
+{
+ return buf->ops->steal(pipe, buf);
+}
+
/* Differs from PIPE_BUF in that PIPE_SIZE is the length of the actual
memory allocation, whereas PIPE_BUF makes atomicity guarantees. */
#define PIPE_SIZE PAGE_SIZE
extern unsigned long pipe_user_pages_soft;
int pipe_proc_fn(struct ctl_table *, int, void __user *, size_t *, loff_t *);
-
/* Drop the inode semaphore and wait for a pipe event, atomically */
void pipe_wait(struct pipe_inode_info *pipe);
int skb_store_bits(struct sk_buff *skb, int offset, const void *from, int len);
__wsum skb_copy_and_csum_bits(const struct sk_buff *skb, int offset, u8 *to,
int len, __wsum csum);
-ssize_t skb_socket_splice(struct sock *sk,
- struct pipe_inode_info *pipe,
- struct splice_pipe_desc *spd);
int skb_splice_bits(struct sk_buff *skb, struct sock *sk, unsigned int offset,
struct pipe_inode_info *pipe, unsigned int len,
- unsigned int flags,
- ssize_t (*splice_cb)(struct sock *,
- struct pipe_inode_info *,
- struct splice_pipe_desc *));
+ unsigned int flags);
void skb_copy_and_csum_dev(const struct sk_buff *skb, u8 *to);
unsigned int skb_zerocopy_headlen(const struct sk_buff *from);
int skb_zerocopy(struct sk_buff *to, struct sk_buff *from,
struct splice_desc *, splice_actor *);
extern ssize_t splice_to_pipe(struct pipe_inode_info *,
struct splice_pipe_desc *);
+extern ssize_t add_to_pipe(struct pipe_inode_info *,
+ struct pipe_buffer *);
extern ssize_t splice_direct_to_actor(struct file *, struct splice_desc *,
splice_direct_actor *);
extern void spd_release_page(struct splice_pipe_desc *, unsigned int);
extern const struct pipe_buf_operations page_cache_pipe_buf_ops;
+extern const struct pipe_buf_operations default_pipe_buf_ops;
#endif
#include <uapi/linux/uio.h>
struct page;
+struct pipe_inode_info;
struct kvec {
void *iov_base; /* and that should *never* hold a userland pointer */
ITER_IOVEC = 0,
ITER_KVEC = 2,
ITER_BVEC = 4,
+ ITER_PIPE = 8,
};
struct iov_iter {
const struct iovec *iov;
const struct kvec *kvec;
const struct bio_vec *bvec;
+ struct pipe_inode_info *pipe;
+ };
+ union {
+ unsigned long nr_segs;
+ int idx;
};
- unsigned long nr_segs;
};
/*
}
#define iov_for_each(iov, iter, start) \
- if (!((start).type & ITER_BVEC)) \
+ if (!((start).type & (ITER_BVEC | ITER_PIPE))) \
for (iter = (start); \
(iter).count && \
((iov = iov_iter_iovec(&(iter))), 1); \
unsigned long nr_segs, size_t count);
void iov_iter_bvec(struct iov_iter *i, int direction, const struct bio_vec *bvec,
unsigned long nr_segs, size_t count);
+void iov_iter_pipe(struct iov_iter *i, int direction, struct pipe_inode_info *pipe,
+ size_t count);
ssize_t iov_iter_get_pages(struct iov_iter *i, struct page **pages,
size_t maxsize, unsigned maxpages, size_t *start);
ssize_t iov_iter_get_pages_alloc(struct iov_iter *i, struct page ***pages,
static inline bool iter_is_iovec(struct iov_iter *i)
{
- return !(i->type & (ITER_BVEC | ITER_KVEC));
+ return !(i->type & (ITER_BVEC | ITER_KVEC | ITER_PIPE));
}
/*
return end_pos;
}
-/*
- * subbuf_read_actor - read up to one subbuf's worth of data
- */
-static int subbuf_read_actor(size_t read_start,
- struct rchan_buf *buf,
- size_t avail,
- read_descriptor_t *desc)
-{
- void *from;
- int ret = 0;
-
- from = buf->start + read_start;
- ret = avail;
- if (copy_to_user(desc->arg.buf, from, avail)) {
- desc->error = -EFAULT;
- ret = 0;
- }
- desc->arg.data += ret;
- desc->written += ret;
- desc->count -= ret;
-
- return ret;
-}
-
-typedef int (*subbuf_actor_t) (size_t read_start,
- struct rchan_buf *buf,
- size_t avail,
- read_descriptor_t *desc);
-
-/*
- * relay_file_read_subbufs - read count bytes, bridging subbuf boundaries
- */
-static ssize_t relay_file_read_subbufs(struct file *filp, loff_t *ppos,
- subbuf_actor_t subbuf_actor,
- read_descriptor_t *desc)
+static ssize_t relay_file_read(struct file *filp,
+ char __user *buffer,
+ size_t count,
+ loff_t *ppos)
{
struct rchan_buf *buf = filp->private_data;
size_t read_start, avail;
+ size_t written = 0;
int ret;
- if (!desc->count)
+ if (!count)
return 0;
inode_lock(file_inode(filp));
do {
+ void *from;
+
if (!relay_file_read_avail(buf, *ppos))
break;
if (!avail)
break;
- avail = min(desc->count, avail);
- ret = subbuf_actor(read_start, buf, avail, desc);
- if (desc->error < 0)
+ avail = min(count, avail);
+ from = buf->start + read_start;
+ ret = avail;
+ if (copy_to_user(buffer, from, avail))
break;
- if (ret) {
- relay_file_read_consume(buf, read_start, ret);
- *ppos = relay_file_read_end_pos(buf, read_start, ret);
- }
- } while (desc->count && ret);
- inode_unlock(file_inode(filp));
+ buffer += ret;
+ written += ret;
+ count -= ret;
- return desc->written;
-}
+ relay_file_read_consume(buf, read_start, ret);
+ *ppos = relay_file_read_end_pos(buf, read_start, ret);
+ } while (count);
+ inode_unlock(file_inode(filp));
-static ssize_t relay_file_read(struct file *filp,
- char __user *buffer,
- size_t count,
- loff_t *ppos)
-{
- read_descriptor_t desc;
- desc.written = 0;
- desc.count = count;
- desc.arg.buf = buffer;
- desc.error = 0;
- return relay_file_read_subbufs(filp, ppos, subbuf_read_actor, &desc);
+ return written;
}
static void relay_consume_bytes(struct rchan_buf *rbuf, int bytes_consumed)
#include <linux/pagemap.h>
#include <linux/slab.h>
#include <linux/vmalloc.h>
+#include <linux/splice.h>
#include <net/checksum.h>
+#define PIPE_PARANOIA /* for now */
+
#define iterate_iovec(i, n, __v, __p, skip, STEP) { \
size_t left; \
size_t wanted = n; \
return wanted - bytes;
}
+#ifdef PIPE_PARANOIA
+static bool sanity(const struct iov_iter *i)
+{
+ struct pipe_inode_info *pipe = i->pipe;
+ int idx = i->idx;
+ int next = pipe->curbuf + pipe->nrbufs;
+ if (i->iov_offset) {
+ struct pipe_buffer *p;
+ if (unlikely(!pipe->nrbufs))
+ goto Bad; // pipe must be non-empty
+ if (unlikely(idx != ((next - 1) & (pipe->buffers - 1))))
+ goto Bad; // must be at the last buffer...
+
+ p = &pipe->bufs[idx];
+ if (unlikely(p->offset + p->len != i->iov_offset))
+ goto Bad; // ... at the end of segment
+ } else {
+ if (idx != (next & (pipe->buffers - 1)))
+ goto Bad; // must be right after the last buffer
+ }
+ return true;
+Bad:
+ printk(KERN_ERR "idx = %d, offset = %zd\n", i->idx, i->iov_offset);
+ printk(KERN_ERR "curbuf = %d, nrbufs = %d, buffers = %d\n",
+ pipe->curbuf, pipe->nrbufs, pipe->buffers);
+ for (idx = 0; idx < pipe->buffers; idx++)
+ printk(KERN_ERR "[%p %p %d %d]\n",
+ pipe->bufs[idx].ops,
+ pipe->bufs[idx].page,
+ pipe->bufs[idx].offset,
+ pipe->bufs[idx].len);
+ WARN_ON(1);
+ return false;
+}
+#else
+#define sanity(i) true
+#endif
+
+static inline int next_idx(int idx, struct pipe_inode_info *pipe)
+{
+ return (idx + 1) & (pipe->buffers - 1);
+}
+
+static size_t copy_page_to_iter_pipe(struct page *page, size_t offset, size_t bytes,
+ struct iov_iter *i)
+{
+ struct pipe_inode_info *pipe = i->pipe;
+ struct pipe_buffer *buf;
+ size_t off;
+ int idx;
+
+ if (unlikely(bytes > i->count))
+ bytes = i->count;
+
+ if (unlikely(!bytes))
+ return 0;
+
+ if (!sanity(i))
+ return 0;
+
+ off = i->iov_offset;
+ idx = i->idx;
+ buf = &pipe->bufs[idx];
+ if (off) {
+ if (offset == off && buf->page == page) {
+ /* merge with the last one */
+ buf->len += bytes;
+ i->iov_offset += bytes;
+ goto out;
+ }
+ idx = next_idx(idx, pipe);
+ buf = &pipe->bufs[idx];
+ }
+ if (idx == pipe->curbuf && pipe->nrbufs)
+ return 0;
+ pipe->nrbufs++;
+ buf->ops = &page_cache_pipe_buf_ops;
+ get_page(buf->page = page);
+ buf->offset = offset;
+ buf->len = bytes;
+ i->iov_offset = offset + bytes;
+ i->idx = idx;
+out:
+ i->count -= bytes;
+ return bytes;
+}
+
/*
* Fault in one or more iovecs of the given iov_iter, to a maximum length of
* bytes. For each iovec, fault in each page that constitutes the iovec.
kunmap_atomic(addr);
}
+static inline bool allocated(struct pipe_buffer *buf)
+{
+ return buf->ops == &default_pipe_buf_ops;
+}
+
+static inline void data_start(const struct iov_iter *i, int *idxp, size_t *offp)
+{
+ size_t off = i->iov_offset;
+ int idx = i->idx;
+ if (off && (!allocated(&i->pipe->bufs[idx]) || off == PAGE_SIZE)) {
+ idx = next_idx(idx, i->pipe);
+ off = 0;
+ }
+ *idxp = idx;
+ *offp = off;
+}
+
+static size_t push_pipe(struct iov_iter *i, size_t size,
+ int *idxp, size_t *offp)
+{
+ struct pipe_inode_info *pipe = i->pipe;
+ size_t off;
+ int idx;
+ ssize_t left;
+
+ if (unlikely(size > i->count))
+ size = i->count;
+ if (unlikely(!size))
+ return 0;
+
+ left = size;
+ data_start(i, &idx, &off);
+ *idxp = idx;
+ *offp = off;
+ if (off) {
+ left -= PAGE_SIZE - off;
+ if (left <= 0) {
+ pipe->bufs[idx].len += size;
+ return size;
+ }
+ pipe->bufs[idx].len = PAGE_SIZE;
+ idx = next_idx(idx, pipe);
+ }
+ while (idx != pipe->curbuf || !pipe->nrbufs) {
+ struct page *page = alloc_page(GFP_USER);
+ if (!page)
+ break;
+ pipe->nrbufs++;
+ pipe->bufs[idx].ops = &default_pipe_buf_ops;
+ pipe->bufs[idx].page = page;
+ pipe->bufs[idx].offset = 0;
+ if (left <= PAGE_SIZE) {
+ pipe->bufs[idx].len = left;
+ return size;
+ }
+ pipe->bufs[idx].len = PAGE_SIZE;
+ left -= PAGE_SIZE;
+ idx = next_idx(idx, pipe);
+ }
+ return size - left;
+}
+
+static size_t copy_pipe_to_iter(const void *addr, size_t bytes,
+ struct iov_iter *i)
+{
+ struct pipe_inode_info *pipe = i->pipe;
+ size_t n, off;
+ int idx;
+
+ if (!sanity(i))
+ return 0;
+
+ bytes = n = push_pipe(i, bytes, &idx, &off);
+ if (unlikely(!n))
+ return 0;
+ for ( ; n; idx = next_idx(idx, pipe), off = 0) {
+ size_t chunk = min_t(size_t, n, PAGE_SIZE - off);
+ memcpy_to_page(pipe->bufs[idx].page, off, addr, chunk);
+ i->idx = idx;
+ i->iov_offset = off + chunk;
+ n -= chunk;
+ addr += chunk;
+ }
+ i->count -= bytes;
+ return bytes;
+}
+
size_t copy_to_iter(const void *addr, size_t bytes, struct iov_iter *i)
{
const char *from = addr;
+ if (unlikely(i->type & ITER_PIPE))
+ return copy_pipe_to_iter(addr, bytes, i);
iterate_and_advance(i, bytes, v,
__copy_to_user(v.iov_base, (from += v.iov_len) - v.iov_len,
v.iov_len),
size_t copy_from_iter(void *addr, size_t bytes, struct iov_iter *i)
{
char *to = addr;
+ if (unlikely(i->type & ITER_PIPE)) {
+ WARN_ON(1);
+ return 0;
+ }
iterate_and_advance(i, bytes, v,
__copy_from_user((to += v.iov_len) - v.iov_len, v.iov_base,
v.iov_len),
size_t copy_from_iter_nocache(void *addr, size_t bytes, struct iov_iter *i)
{
char *to = addr;
+ if (unlikely(i->type & ITER_PIPE)) {
+ WARN_ON(1);
+ return 0;
+ }
iterate_and_advance(i, bytes, v,
__copy_from_user_nocache((to += v.iov_len) - v.iov_len,
v.iov_base, v.iov_len),
size_t wanted = copy_to_iter(kaddr + offset, bytes, i);
kunmap_atomic(kaddr);
return wanted;
- } else
+ } else if (likely(!(i->type & ITER_PIPE)))
return copy_page_to_iter_iovec(page, offset, bytes, i);
+ else
+ return copy_page_to_iter_pipe(page, offset, bytes, i);
}
EXPORT_SYMBOL(copy_page_to_iter);
size_t copy_page_from_iter(struct page *page, size_t offset, size_t bytes,
struct iov_iter *i)
{
+ if (unlikely(i->type & ITER_PIPE)) {
+ WARN_ON(1);
+ return 0;
+ }
if (i->type & (ITER_BVEC|ITER_KVEC)) {
void *kaddr = kmap_atomic(page);
size_t wanted = copy_from_iter(kaddr + offset, bytes, i);
}
EXPORT_SYMBOL(copy_page_from_iter);
+static size_t pipe_zero(size_t bytes, struct iov_iter *i)
+{
+ struct pipe_inode_info *pipe = i->pipe;
+ size_t n, off;
+ int idx;
+
+ if (!sanity(i))
+ return 0;
+
+ bytes = n = push_pipe(i, bytes, &idx, &off);
+ if (unlikely(!n))
+ return 0;
+
+ for ( ; n; idx = next_idx(idx, pipe), off = 0) {
+ size_t chunk = min_t(size_t, n, PAGE_SIZE - off);
+ memzero_page(pipe->bufs[idx].page, off, chunk);
+ i->idx = idx;
+ i->iov_offset = off + chunk;
+ n -= chunk;
+ }
+ i->count -= bytes;
+ return bytes;
+}
+
size_t iov_iter_zero(size_t bytes, struct iov_iter *i)
{
+ if (unlikely(i->type & ITER_PIPE))
+ return pipe_zero(bytes, i);
iterate_and_advance(i, bytes, v,
__clear_user(v.iov_base, v.iov_len),
memzero_page(v.bv_page, v.bv_offset, v.bv_len),
struct iov_iter *i, unsigned long offset, size_t bytes)
{
char *kaddr = kmap_atomic(page), *p = kaddr + offset;
+ if (unlikely(i->type & ITER_PIPE)) {
+ kunmap_atomic(kaddr);
+ WARN_ON(1);
+ return 0;
+ }
iterate_all_kinds(i, bytes, v,
__copy_from_user_inatomic((p += v.iov_len) - v.iov_len,
v.iov_base, v.iov_len),
}
EXPORT_SYMBOL(iov_iter_copy_from_user_atomic);
+static void pipe_advance(struct iov_iter *i, size_t size)
+{
+ struct pipe_inode_info *pipe = i->pipe;
+ struct pipe_buffer *buf;
+ int idx = i->idx;
+ size_t off = i->iov_offset;
+
+ if (unlikely(i->count < size))
+ size = i->count;
+
+ if (size) {
+ if (off) /* make it relative to the beginning of buffer */
+ size += off - pipe->bufs[idx].offset;
+ while (1) {
+ buf = &pipe->bufs[idx];
+ if (size <= buf->len)
+ break;
+ size -= buf->len;
+ idx = next_idx(idx, pipe);
+ }
+ buf->len = size;
+ i->idx = idx;
+ off = i->iov_offset = buf->offset + size;
+ }
+ if (off)
+ idx = next_idx(idx, pipe);
+ if (pipe->nrbufs) {
+ int unused = (pipe->curbuf + pipe->nrbufs) & (pipe->buffers - 1);
+ /* [curbuf,unused) is in use. Free [idx,unused) */
+ while (idx != unused) {
+ pipe_buf_release(pipe, &pipe->bufs[idx]);
+ idx = next_idx(idx, pipe);
+ pipe->nrbufs--;
+ }
+ }
+}
+
void iov_iter_advance(struct iov_iter *i, size_t size)
{
+ if (unlikely(i->type & ITER_PIPE)) {
+ pipe_advance(i, size);
+ return;
+ }
iterate_and_advance(i, size, v, 0, 0, 0)
}
EXPORT_SYMBOL(iov_iter_advance);
*/
size_t iov_iter_single_seg_count(const struct iov_iter *i)
{
+ if (unlikely(i->type & ITER_PIPE))
+ return i->count; // it is a silly place, anyway
if (i->nr_segs == 1)
return i->count;
else if (i->type & ITER_BVEC)
}
EXPORT_SYMBOL(iov_iter_bvec);
+void iov_iter_pipe(struct iov_iter *i, int direction,
+ struct pipe_inode_info *pipe,
+ size_t count)
+{
+ BUG_ON(direction != ITER_PIPE);
+ i->type = direction;
+ i->pipe = pipe;
+ i->idx = (pipe->curbuf + pipe->nrbufs) & (pipe->buffers - 1);
+ i->iov_offset = 0;
+ i->count = count;
+}
+EXPORT_SYMBOL(iov_iter_pipe);
+
unsigned long iov_iter_alignment(const struct iov_iter *i)
{
unsigned long res = 0;
if (!size)
return 0;
+ if (unlikely(i->type & ITER_PIPE)) {
+ if (i->iov_offset && allocated(&i->pipe->bufs[i->idx]))
+ return size | i->iov_offset;
+ return size;
+ }
iterate_all_kinds(i, size, v,
(res |= (unsigned long)v.iov_base | v.iov_len, 0),
res |= v.bv_offset | v.bv_len,
if (!size)
return 0;
+ if (unlikely(i->type & ITER_PIPE)) {
+ WARN_ON(1);
+ return ~0U;
+ }
+
iterate_all_kinds(i, size, v,
(res |= (!res ? 0 : (unsigned long)v.iov_base) |
(size != v.iov_len ? size : 0), 0),
}
EXPORT_SYMBOL(iov_iter_gap_alignment);
+static inline size_t __pipe_get_pages(struct iov_iter *i,
+ size_t maxsize,
+ struct page **pages,
+ int idx,
+ size_t *start)
+{
+ struct pipe_inode_info *pipe = i->pipe;
+ size_t n = push_pipe(i, maxsize, &idx, start);
+ if (!n)
+ return -EFAULT;
+
+ maxsize = n;
+ n += *start;
+ while (n >= PAGE_SIZE) {
+ get_page(*pages++ = pipe->bufs[idx].page);
+ idx = next_idx(idx, pipe);
+ n -= PAGE_SIZE;
+ }
+
+ return maxsize;
+}
+
+static ssize_t pipe_get_pages(struct iov_iter *i,
+ struct page **pages, size_t maxsize, unsigned maxpages,
+ size_t *start)
+{
+ unsigned npages;
+ size_t capacity;
+ int idx;
+
+ if (!sanity(i))
+ return -EFAULT;
+
+ data_start(i, &idx, start);
+ /* some of this one + all after this one */
+ npages = ((i->pipe->curbuf - idx - 1) & (i->pipe->buffers - 1)) + 1;
+ capacity = min(npages,maxpages) * PAGE_SIZE - *start;
+
+ return __pipe_get_pages(i, min(maxsize, capacity), pages, idx, start);
+}
+
ssize_t iov_iter_get_pages(struct iov_iter *i,
struct page **pages, size_t maxsize, unsigned maxpages,
size_t *start)
if (!maxsize)
return 0;
+ if (unlikely(i->type & ITER_PIPE))
+ return pipe_get_pages(i, pages, maxsize, maxpages, start);
iterate_all_kinds(i, maxsize, v, ({
unsigned long addr = (unsigned long)v.iov_base;
size_t len = v.iov_len + (*start = addr & (PAGE_SIZE - 1));
return p;
}
+static ssize_t pipe_get_pages_alloc(struct iov_iter *i,
+ struct page ***pages, size_t maxsize,
+ size_t *start)
+{
+ struct page **p;
+ size_t n;
+ int idx;
+ int npages;
+
+ if (!sanity(i))
+ return -EFAULT;
+
+ data_start(i, &idx, start);
+ /* some of this one + all after this one */
+ npages = ((i->pipe->curbuf - idx - 1) & (i->pipe->buffers - 1)) + 1;
+ n = npages * PAGE_SIZE - *start;
+ if (maxsize > n)
+ maxsize = n;
+ else
+ npages = DIV_ROUND_UP(maxsize + *start, PAGE_SIZE);
+ p = get_pages_array(npages);
+ if (!p)
+ return -ENOMEM;
+ n = __pipe_get_pages(i, maxsize, p, idx, start);
+ if (n > 0)
+ *pages = p;
+ else
+ kvfree(p);
+ return n;
+}
+
ssize_t iov_iter_get_pages_alloc(struct iov_iter *i,
struct page ***pages, size_t maxsize,
size_t *start)
if (!maxsize)
return 0;
+ if (unlikely(i->type & ITER_PIPE))
+ return pipe_get_pages_alloc(i, pages, maxsize, start);
iterate_all_kinds(i, maxsize, v, ({
unsigned long addr = (unsigned long)v.iov_base;
size_t len = v.iov_len + (*start = addr & (PAGE_SIZE - 1));
__wsum sum, next;
size_t off = 0;
sum = *csum;
+ if (unlikely(i->type & ITER_PIPE)) {
+ WARN_ON(1);
+ return 0;
+ }
iterate_and_advance(i, bytes, v, ({
int err = 0;
next = csum_and_copy_from_user(v.iov_base,
__wsum sum, next;
size_t off = 0;
sum = *csum;
+ if (unlikely(i->type & ITER_PIPE)) {
+ WARN_ON(1); /* for now */
+ return 0;
+ }
iterate_and_advance(i, bytes, v, ({
int err = 0;
next = csum_and_copy_to_user((from += v.iov_len) - v.iov_len,
if (!size)
return 0;
- iterate_all_kinds(i, size, v, ({
+ if (unlikely(i->type & ITER_PIPE)) {
+ struct pipe_inode_info *pipe = i->pipe;
+ size_t off;
+ int idx;
+
+ if (!sanity(i))
+ return 0;
+
+ data_start(i, &idx, &off);
+ /* some of this one + all after this one */
+ npages = ((pipe->curbuf - idx - 1) & (pipe->buffers - 1)) + 1;
+ if (npages >= maxpages)
+ return maxpages;
+ } else iterate_all_kinds(i, size, v, ({
unsigned long p = (unsigned long)v.iov_base;
npages += DIV_ROUND_UP(p + v.iov_len, PAGE_SIZE)
- p / PAGE_SIZE;
const void *dup_iter(struct iov_iter *new, struct iov_iter *old, gfp_t flags)
{
*new = *old;
+ if (unlikely(new->type & ITER_PIPE)) {
+ WARN_ON(1);
+ return NULL;
+ }
if (new->type & ITER_BVEC)
return new->bvec = kmemdup(new->bvec,
new->nr_segs * sizeof(struct bio_vec),
return retval ? retval : error;
}
-static ssize_t shmem_file_splice_read(struct file *in, loff_t *ppos,
- struct pipe_inode_info *pipe, size_t len,
- unsigned int flags)
-{
- struct address_space *mapping = in->f_mapping;
- struct inode *inode = mapping->host;
- unsigned int loff, nr_pages, req_pages;
- struct page *pages[PIPE_DEF_BUFFERS];
- struct partial_page partial[PIPE_DEF_BUFFERS];
- struct page *page;
- pgoff_t index, end_index;
- loff_t isize, left;
- int error, page_nr;
- struct splice_pipe_desc spd = {
- .pages = pages,
- .partial = partial,
- .nr_pages_max = PIPE_DEF_BUFFERS,
- .flags = flags,
- .ops = &page_cache_pipe_buf_ops,
- .spd_release = spd_release_page,
- };
-
- isize = i_size_read(inode);
- if (unlikely(*ppos >= isize))
- return 0;
-
- left = isize - *ppos;
- if (unlikely(left < len))
- len = left;
-
- if (splice_grow_spd(pipe, &spd))
- return -ENOMEM;
-
- index = *ppos >> PAGE_SHIFT;
- loff = *ppos & ~PAGE_MASK;
- req_pages = (len + loff + PAGE_SIZE - 1) >> PAGE_SHIFT;
- nr_pages = min(req_pages, spd.nr_pages_max);
-
- spd.nr_pages = find_get_pages_contig(mapping, index,
- nr_pages, spd.pages);
- index += spd.nr_pages;
- error = 0;
-
- while (spd.nr_pages < nr_pages) {
- error = shmem_getpage(inode, index, &page, SGP_CACHE);
- if (error)
- break;
- unlock_page(page);
- spd.pages[spd.nr_pages++] = page;
- index++;
- }
-
- index = *ppos >> PAGE_SHIFT;
- nr_pages = spd.nr_pages;
- spd.nr_pages = 0;
-
- for (page_nr = 0; page_nr < nr_pages; page_nr++) {
- unsigned int this_len;
-
- if (!len)
- break;
-
- this_len = min_t(unsigned long, len, PAGE_SIZE - loff);
- page = spd.pages[page_nr];
-
- if (!PageUptodate(page) || page->mapping != mapping) {
- error = shmem_getpage(inode, index, &page, SGP_CACHE);
- if (error)
- break;
- unlock_page(page);
- put_page(spd.pages[page_nr]);
- spd.pages[page_nr] = page;
- }
-
- isize = i_size_read(inode);
- end_index = (isize - 1) >> PAGE_SHIFT;
- if (unlikely(!isize || index > end_index))
- break;
-
- if (end_index == index) {
- unsigned int plen;
-
- plen = ((isize - 1) & ~PAGE_MASK) + 1;
- if (plen <= loff)
- break;
-
- this_len = min(this_len, plen - loff);
- len = this_len;
- }
-
- spd.partial[page_nr].offset = loff;
- spd.partial[page_nr].len = this_len;
- len -= this_len;
- loff = 0;
- spd.nr_pages++;
- index++;
- }
-
- while (page_nr < nr_pages)
- put_page(spd.pages[page_nr++]);
-
- if (spd.nr_pages)
- error = splice_to_pipe(pipe, &spd);
-
- splice_shrink_spd(&spd);
-
- if (error > 0) {
- *ppos += error;
- file_accessed(in);
- }
- return error;
-}
-
/*
* llseek SEEK_DATA or SEEK_HOLE through the radix_tree.
*/
.read_iter = shmem_file_read_iter,
.write_iter = generic_file_write_iter,
.fsync = noop_fsync,
- .splice_read = shmem_file_splice_read,
+ .splice_read = generic_file_splice_read,
.splice_write = iter_file_splice_write,
.fallocate = shmem_fallocate,
#endif
return false;
}
-ssize_t skb_socket_splice(struct sock *sk,
- struct pipe_inode_info *pipe,
- struct splice_pipe_desc *spd)
-{
- int ret;
-
- /* Drop the socket lock, otherwise we have reverse
- * locking dependencies between sk_lock and i_mutex
- * here as compared to sendfile(). We enter here
- * with the socket lock held, and splice_to_pipe() will
- * grab the pipe inode lock. For sendfile() emulation,
- * we call into ->sendpage() with the i_mutex lock held
- * and networking will grab the socket lock.
- */
- release_sock(sk);
- ret = splice_to_pipe(pipe, spd);
- lock_sock(sk);
-
- return ret;
-}
-
/*
* Map data from the skb to a pipe. Should handle both the linear part,
* the fragments, and the frag list.
*/
int skb_splice_bits(struct sk_buff *skb, struct sock *sk, unsigned int offset,
struct pipe_inode_info *pipe, unsigned int tlen,
- unsigned int flags,
- ssize_t (*splice_cb)(struct sock *,
- struct pipe_inode_info *,
- struct splice_pipe_desc *))
+ unsigned int flags)
{
struct partial_page partial[MAX_SKB_FRAGS];
struct page *pages[MAX_SKB_FRAGS];
__skb_splice_bits(skb, pipe, &offset, &tlen, &spd, sk);
if (spd.nr_pages)
- ret = splice_cb(sk, pipe, &spd);
+ ret = splice_to_pipe(pipe, &spd);
return ret;
}
int ret;
ret = skb_splice_bits(skb, skb->sk, offset, tss->pipe,
- min(rd_desc->count, len), tss->flags,
- skb_socket_splice);
+ min(rd_desc->count, len), tss->flags);
if (ret > 0)
rd_desc->count -= ret;
return ret;
return copied ? : err;
}
-static ssize_t kcm_sock_splice(struct sock *sk,
- struct pipe_inode_info *pipe,
- struct splice_pipe_desc *spd)
-{
- int ret;
-
- release_sock(sk);
- ret = splice_to_pipe(pipe, spd);
- lock_sock(sk);
-
- return ret;
-}
-
static ssize_t kcm_splice_read(struct socket *sock, loff_t *ppos,
struct pipe_inode_info *pipe, size_t len,
unsigned int flags)
if (len > rxm->full_len)
len = rxm->full_len;
- copied = skb_splice_bits(skb, sk, rxm->offset, pipe, len, flags,
- kcm_sock_splice);
+ copied = skb_splice_bits(skb, sk, rxm->offset, pipe, len, flags);
if (copied < 0) {
err = copied;
goto err_out;
return unix_stream_read_generic(&state);
}
-static ssize_t skb_unix_socket_splice(struct sock *sk,
- struct pipe_inode_info *pipe,
- struct splice_pipe_desc *spd)
-{
- int ret;
- struct unix_sock *u = unix_sk(sk);
-
- mutex_unlock(&u->iolock);
- ret = splice_to_pipe(pipe, spd);
- mutex_lock(&u->iolock);
-
- return ret;
-}
-
static int unix_stream_splice_actor(struct sk_buff *skb,
int skip, int chunk,
struct unix_stream_read_state *state)
{
return skb_splice_bits(skb, state->socket->sk,
UNIXCB(skb).consumed + skip,
- state->pipe, chunk, state->splice_flags,
- skb_unix_socket_splice);
+ state->pipe, chunk, state->splice_flags);
}
static ssize_t unix_stream_splice_read(struct socket *sock, loff_t *ppos,
projects / cascardo / linux.git / commitdiff