From 82c156f853840645604acd7c2cebcb75ed1b6652 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Thu, 22 Sep 2016 23:35:42 -0400 Subject: switch generic_file_splice_read() to use of ->read_iter() ... and kill the ->splice_read() instances that can be switched to it Signed-off-by: Al Viro diff --git a/drivers/staging/lustre/lustre/llite/file.c b/drivers/staging/lustre/lustre/llite/file.c index 57281b9..2567b09 100644 --- a/drivers/staging/lustre/lustre/llite/file.c +++ b/drivers/staging/lustre/lustre/llite/file.c @@ -1153,36 +1153,21 @@ restart: 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 { @@ -1237,7 +1222,7 @@ static ssize_t ll_file_read_iter(struct kiocb *iocb, struct iov_iter *to) 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; @@ -1261,7 +1246,7 @@ static ssize_t ll_file_write_iter(struct kiocb *iocb, struct iov_iter *from) 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; @@ -1271,31 +1256,6 @@ static ssize_t ll_file_write_iter(struct kiocb *iocb, struct iov_iter *from) 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); @@ -3173,7 +3133,7 @@ struct file_operations ll_file_operations = { .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 }; @@ -3186,7 +3146,7 @@ struct file_operations ll_file_operations_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_flock, @@ -3202,7 +3162,7 @@ struct file_operations ll_file_operations_noflock = { .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, diff --git a/drivers/staging/lustre/lustre/llite/llite_internal.h b/drivers/staging/lustre/lustre/llite/llite_internal.h index 4d6d589..0e738c8 100644 --- a/drivers/staging/lustre/lustre/llite/llite_internal.h +++ b/drivers/staging/lustre/lustre/llite/llite_internal.h @@ -800,17 +800,11 @@ void vvp_write_complete(struct vvp_object *club, struct vvp_page *page); */ 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; }; @@ -838,14 +832,9 @@ static inline struct ll_thread_info *ll_env_info(const struct lu_env *env) 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); diff --git a/drivers/staging/lustre/lustre/llite/vvp_internal.h b/drivers/staging/lustre/lustre/llite/vvp_internal.h index 79fc428..2fa49cc 100644 --- a/drivers/staging/lustre/lustre/llite/vvp_internal.h +++ b/drivers/staging/lustre/lustre/llite/vvp_internal.h @@ -49,14 +49,6 @@ struct obd_device; 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. */ @@ -99,10 +91,6 @@ struct vvp_io { 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; int vui_from; @@ -110,8 +98,6 @@ struct vvp_io { } write; } u; - enum vvp_io_subtype vui_io_subtype; - /** * Layout version when this IO is initialized */ diff --git a/drivers/staging/lustre/lustre/llite/vvp_io.c b/drivers/staging/lustre/lustre/llite/vvp_io.c index 94916dc..4864600 100644 --- a/drivers/staging/lustre/lustre/llite/vvp_io.c +++ b/drivers/staging/lustre/lustre/llite/vvp_io.c @@ -55,18 +55,6 @@ static struct vvp_io *cl2vvp_io(const struct lu_env *env, } /** - * 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 * correctness of layout. It works because swapping layout processes @@ -391,9 +379,6 @@ static int vvp_mmap_locks(const struct lu_env *env, 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; @@ -462,15 +447,10 @@ static void vvp_io_advance(const struct lu_env *env, 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); } @@ -479,7 +459,7 @@ static void vvp_io_update_iov(const struct lu_env *env, { 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); @@ -716,25 +696,8 @@ static int vvp_io_read_start(const struct lu_env *env, /* 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) { diff --git a/fs/coda/file.c b/fs/coda/file.c index f47c748..8415d4f 100644 --- a/fs/coda/file.c +++ b/fs/coda/file.c @@ -38,27 +38,6 @@ coda_file_read_iter(struct kiocb *iocb, struct iov_iter *to) } 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) { struct file *coda_file = iocb->ki_filp; @@ -225,6 +204,6 @@ const struct file_operations coda_file_operations = { .open = coda_open, .release = coda_release, .fsync = coda_fsync, - .splice_read = coda_file_splice_read, + .splice_read = generic_file_splice_read, }; diff --git a/fs/gfs2/file.c b/fs/gfs2/file.c index 320e65e..7016a6a7 100644 --- a/fs/gfs2/file.c +++ b/fs/gfs2/file.c @@ -954,30 +954,6 @@ out_uninit: 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) @@ -1140,7 +1116,7 @@ const struct file_operations gfs2_file_fops = { .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, @@ -1168,7 +1144,7 @@ const struct file_operations gfs2_file_fops_nolock = { .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, diff --git a/fs/nfs/file.c b/fs/nfs/file.c index ca699dd..2efbdde 100644 --- a/fs/nfs/file.c +++ b/fs/nfs/file.c @@ -182,29 +182,6 @@ nfs_file_read(struct kiocb *iocb, struct iov_iter *to) } 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) { @@ -871,7 +848,7 @@ const struct file_operations nfs_file_operations = { .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, diff --git a/fs/nfs/internal.h b/fs/nfs/internal.h index 74935a1..d7b062b 100644 --- a/fs/nfs/internal.h +++ b/fs/nfs/internal.h @@ -365,8 +365,6 @@ int nfs_rename(struct inode *, struct dentry *, struct inode *, struct dentry *) 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 *); diff --git a/fs/nfs/nfs4file.c b/fs/nfs/nfs4file.c index d085ad7..89a7795 100644 --- a/fs/nfs/nfs4file.c +++ b/fs/nfs/nfs4file.c @@ -248,7 +248,7 @@ const struct file_operations nfs4_file_operations = { .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, diff --git a/fs/ocfs2/file.c b/fs/ocfs2/file.c index 0b055bf..8f91639 100644 --- a/fs/ocfs2/file.c +++ b/fs/ocfs2/file.c @@ -2321,36 +2321,6 @@ out_mutex: 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) { @@ -2509,7 +2479,7 @@ const struct file_operations ocfs2_fops = { #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, }; @@ -2554,7 +2524,7 @@ const struct file_operations ocfs2_fops_no_plocks = { .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, }; diff --git a/fs/ocfs2/ocfs2_trace.h b/fs/ocfs2/ocfs2_trace.h index f8f5fc5..0b58abc 100644 --- a/fs/ocfs2/ocfs2_trace.h +++ b/fs/ocfs2/ocfs2_trace.h @@ -1314,8 +1314,6 @@ DEFINE_OCFS2_FILE_OPS(ocfs2_file_aio_write); 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); diff --git a/fs/splice.c b/fs/splice.c index 589a1d5..58c322a 100644 --- a/fs/splice.c +++ b/fs/splice.c @@ -281,207 +281,6 @@ void splice_shrink_spd(struct splice_pipe_desc *spd) 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 @@ -492,32 +291,46 @@ fill_it: * * 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; @@ -580,7 +393,7 @@ ssize_t kernel_write(struct file *file, const char *buf, size_t count, } 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) { @@ -675,7 +488,6 @@ err: res = error; goto shrink_ret; } -EXPORT_SYMBOL(default_file_splice_read); /* * Send 'sd->len' bytes to socket from 'sd->file' at position 'sd->pos' diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c index e612a02..92f16cf 100644 --- a/fs/xfs/xfs_file.c +++ b/fs/xfs/xfs_file.c @@ -399,45 +399,6 @@ xfs_file_read_iter( 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. * @@ -1652,7 +1613,7 @@ const struct file_operations xfs_file_operations = { .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 diff --git a/fs/xfs/xfs_trace.h b/fs/xfs/xfs_trace.h index d303a66..f31db44 100644 --- a/fs/xfs/xfs_trace.h +++ b/fs/xfs/xfs_trace.h @@ -1170,7 +1170,6 @@ DEFINE_RW_EVENT(xfs_file_dax_read); 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, diff --git a/include/linux/fs.h b/include/linux/fs.h index 901e25d..b04883e 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -2794,8 +2794,6 @@ extern void block_sync_page(struct page *page); /* 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, diff --git a/mm/shmem.c b/mm/shmem.c index 971fc83..d86b5e4 100644 --- a/mm/shmem.c +++ b/mm/shmem.c @@ -2311,119 +2311,6 @@ static ssize_t shmem_file_read_iter(struct kiocb *iocb, struct iov_iter *to) 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. */ @@ -3786,7 +3673,7 @@ static const struct file_operations shmem_file_operations = { .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 -- cgit v0.10.2