On Fri, Jun 01 2007, Jens Axboe wrote: > On Fri, Jun 01 2007, Neil Brown wrote: > > > > Ok, here is a patch that makes nfsd use splice instead of sendfile. > > It appears to both compile and work. > > > > Some observations: > > - __splice_from_pipe wants a "struct file*" and I wanted to pass a > > "struct svcrqst *". Maybe it should take a void * ? > > - It also wants a *ppos which I had no use for.. It that really > > need? Cannot &file->f_pos be used? > > See: > > http://git.kernel.dk/?p=linux-2.6-block.git;a=commitdiff;h=c73a9509ef7877d31e0c97c684ee8b7ed13ecbbe;hp=07f0e716250d4a3a550b2f39bd0a7e4e6566b3c2 > > I'll rebase the conversion on top of this one, loop will need the same > change. > > > - I copied do_splice_to from splice.c as it wasn't exported, and > > then found I couldn't compile because rw_verify_area wasn't > > exported. As nfsd doesn't need that (we never export > > mandatory-locking files) I just remove it and some other cruft > > that I didn't need.... Not sure if that was the best approach. > > - I needed to export alloc_pipe_info. Maybe there should be a > > get_current_pipe instead which does the alloc if needed. > > - I would much rather have something like free_pipe_info exported > > than open code it in do_splice_read (which is based heavily on > > do_splice_direct). > > I need the same thing for loop. I think I'll add do_splice_foo() to > fs/splice.c in a way that loop can use instead of do_splice_direct(), > then nfsd should be able to do the same.
I rebased and added a splice_direct_to_actor() helper that nfsd can then use. This makes the nfsd diff look like the below, which I think you'll agree is a lot more pleasant. You can view the tree here: http://git.kernel.dk/?p=linux-2.6-block.git;a=shortlog;h=splice The vmsplice patch probably needs to be split in two, for now it is the one introducing the framework that nfsd (and next, loop) can use. diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c index 7e6aa24..96f76e2 100644 --- a/fs/nfsd/vfs.c +++ b/fs/nfsd/vfs.c @@ -23,7 +23,7 @@ #include <linux/file.h> #include <linux/mount.h> #include <linux/major.h> -#include <linux/ext2_fs.h> +#include <linux/pipe_fs_i.h> #include <linux/proc_fs.h> #include <linux/stat.h> #include <linux/fcntl.h> @@ -801,26 +801,32 @@ found: } /* - * Grab and keep cached pages assosiated with a file in the svc_rqst - * so that they can be passed to the netowork sendmsg/sendpage routines - * directrly. They will be released after the sending has completed. + * Grab and keep cached pages associated with a file in the svc_rqst + * so that they can be passed to the network sendmsg/sendpage routines + * directly. They will be released after the sending has completed. */ static int -nfsd_read_actor(read_descriptor_t *desc, struct page *page, unsigned long offset , unsigned long size) +nfsd_splice_actor(struct pipe_inode_info *pipe, struct pipe_buffer *buf, + struct splice_desc *sd) { - unsigned long count = desc->count; - struct svc_rqst *rqstp = desc->arg.data; + struct svc_rqst *rqstp = sd->data; struct page **pp = rqstp->rq_respages + rqstp->rq_resused; + struct page *page = buf->page; + size_t size; + int ret; + + ret = buf->ops->pin(pipe, buf); + if (unlikely(ret)) + return ret; - if (size > count) - size = count; + size = sd->len; if (rqstp->rq_res.page_len == 0) { get_page(page); put_page(*pp); *pp = page; rqstp->rq_resused++; - rqstp->rq_res.page_base = offset; + rqstp->rq_res.page_base = buf->offset; rqstp->rq_res.page_len = size; } else if (page != pp[-1]) { get_page(page); @@ -832,11 +838,15 @@ nfsd_read_actor(read_descriptor_t *desc, struct page *page, unsigned long offset } else rqstp->rq_res.page_len += size; - desc->count = count - size; - desc->written += size; return size; } +static int nfsd_direct_splice_actor(struct pipe_inode_info *pipe, + struct splice_desc *sd) +{ + return __splice_from_pipe(pipe, sd, nfsd_splice_actor); +} + static __be32 nfsd_vfs_read(struct svc_rqst *rqstp, struct svc_fh *fhp, struct file *file, loff_t offset, struct kvec *vec, int vlen, unsigned long *count) @@ -861,10 +871,15 @@ nfsd_vfs_read(struct svc_rqst *rqstp, struct svc_fh *fhp, struct file *file, if (ra && ra->p_set) file->f_ra = ra->p_ra; - if (file->f_op->sendfile && rqstp->rq_sendfile_ok) { - rqstp->rq_resused = 1; - host_err = file->f_op->sendfile(file, &offset, *count, - nfsd_read_actor, rqstp); + if (file->f_op->splice_read && rqstp->rq_splice_ok) { + struct splice_desc sd = { + .len = 0, + .total_len = *count, + .pos = offset, + }; + + sd.data = rqstp; + host_err = splice_direct_to_actor(file, &sd, nfsd_direct_splice_actor); } else { oldfs = get_fs(); set_fs(KERNEL_DS); -- Jens Axboe - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
