int write_mutex_locked = 0;
vio->vui_fd = LUSTRE_FPRIVATE(file);
- vio->vui_io_subtype = args->via_io_subtype;
-
- switch (vio->vui_io_subtype) {
- case IO_NORMAL:
- vio->vui_iter = args->u.normal.via_iter;
- vio->vui_iocb = args->u.normal.via_iocb;
- if ((iot == CIT_WRITE) &&
- !(vio->vui_fd->fd_flags & LL_FILE_GROUP_LOCKED)) {
- if (mutex_lock_interruptible(&lli->
- lli_write_mutex)) {
- result = -ERESTARTSYS;
- goto out;
- }
- write_mutex_locked = 1;
+ vio->vui_iter = args->u.normal.via_iter;
+ vio->vui_iocb = args->u.normal.via_iocb;
+ if ((iot == CIT_WRITE) &&
+ !(vio->vui_fd->fd_flags & LL_FILE_GROUP_LOCKED)) {
+ if (mutex_lock_interruptible(&lli->lli_write_mutex)) {
+ result = -ERESTARTSYS;
+ goto out;
}
- 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();
+ write_mutex_locked = 1;
}
+ 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 (write_mutex_locked)
mutex_unlock(&lli->lli_write_mutex);
} else {
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;
-}
-
static int ll_lov_recreate(struct inode *inode, struct ost_id *oi, u32 ost_idx)
{
struct obd_export *exp = ll_i2dtexp(inode);
.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,
};
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);
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(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)
{
res = error;
goto shrink_ret;
}
-EXPORT_SYMBOL(default_file_splice_read);
/*
* Send 'sd->len' bytes to socket from 'sd->file' at position 'sd->pos'
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,
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
projects / cascardo / linux.git / commitdiff