On 10/22/2012 10:21 AM, Myklebust, Trond wrote: >> -----Original Message----- >> From: Dave Kleikamp [mailto:dave.kleikamp@xxxxxxxxxx] >> Sent: Monday, October 22, 2012 11:15 AM >> To: linux-fsdevel@xxxxxxxxxxxxxxx >> Cc: linux-kernel@xxxxxxxxxxxxxxx; Zach Brown; Maxim V. Patlasov; Dave >> Kleikamp; Myklebust, Trond; linux-nfs@xxxxxxxxxxxxxxx >> Subject: [PATCH 20/22] nfs: add support for read_iter, write_iter >> >> This patch implements the read_iter and write_iter file operations which >> allow kernel code to initiate directIO. This allows the loop device to read and >> write directly to the server, bypassing the page cache. >> >> Signed-off-by: Dave Kleikamp <dave.kleikamp@xxxxxxxxxx> >> Cc: Zach Brown <zab@xxxxxxxxx> >> Cc: Trond Myklebust <Trond.Myklebust@xxxxxxxxxx> >> Cc: linux-nfs@xxxxxxxxxxxxxxx >> --- >> fs/nfs/direct.c | 169 +++++++++++++++++++++++++++++++++----------- >> ----- >> fs/nfs/file.c | 48 ++++++++++---- >> fs/nfs/internal.h | 2 + >> fs/nfs/nfs4file.c | 2 + >> include/linux/nfs_fs.h | 6 +- >> 5 files changed, 155 insertions(+), 72 deletions(-) >> >> diff --git a/fs/nfs/direct.c b/fs/nfs/direct.c index 4532781..b1fda1c 100644 >> --- a/fs/nfs/direct.c >> +++ b/fs/nfs/direct.c >> @@ -429,16 +428,47 @@ static ssize_t >> nfs_direct_read_schedule_iovec(struct nfs_direct_req *dreq, >> get_dreq(dreq); >> desc.pg_dreq = dreq; >> >> - for (seg = 0; seg < nr_segs; seg++) { >> - const struct iovec *vec = &iov[seg]; >> - result = nfs_direct_read_schedule_segment(&desc, vec, >> pos, uio); >> - if (result < 0) >> - break; >> - requested_bytes += result; >> - if ((size_t)result < vec->iov_len) >> - break; >> - pos += vec->iov_len; >> - } >> + if (iov_iter_has_iovec(iter)) { >> + const struct iovec *iov = iov_iter_iovec(iter); >> + if (uio) >> + dreq->flags = NFS_ODIRECT_MARK_DIRTY; >> + for (seg = 0; seg < iter->nr_segs; seg++) { >> + const struct iovec *vec = &iov[seg]; >> + result = nfs_direct_read_schedule_segment(&desc, >> vec, >> + pos, uio); >> + if (result < 0) >> + break; >> + requested_bytes += result; >> + if ((size_t)result < vec->iov_len) >> + break; >> + pos += vec->iov_len; >> + } >> + } else if (iov_iter_has_bvec(iter)) { >> + struct nfs_open_context *ctx = dreq->ctx; >> + struct inode *inode = ctx->dentry->d_inode; >> + struct bio_vec *bvec = iov_iter_bvec(iter); >> + for (seg = 0; seg < iter->nr_segs; seg++) { >> + struct nfs_page *req; >> + unsigned int req_len = bvec[seg].bv_len; >> + req = nfs_create_request(ctx, inode, >> + bvec[seg].bv_page, >> + bvec[seg].bv_offset, >> req_len); >> + if (IS_ERR(req)) { >> + result = PTR_ERR(req); >> + break; >> + } >> + req->wb_index = pos >> PAGE_SHIFT; >> + req->wb_offset = pos & ~PAGE_MASK; >> + if (!nfs_pageio_add_request(&desc, req)) { >> + result = desc.pg_error; >> + nfs_release_request(req); >> + break; >> + } >> + requested_bytes += req_len; >> + pos += req_len; >> + } >> + } else >> + BUG(); > > Can we please split the contents of these 2 if statements into 2 helper functions nfs_direct_do_schedule_read_iovec() and nfs_direct_do_schedule_read_bvec()? > Sure, no problem. >> @@ -832,17 +861,48 @@ static ssize_t >> nfs_direct_write_schedule_iovec(struct nfs_direct_req *dreq, >> get_dreq(dreq); >> atomic_inc(&inode->i_dio_count); >> >> - NFS_I(dreq->inode)->write_io += iov_length(iov, nr_segs); >> - for (seg = 0; seg < nr_segs; seg++) { >> - const struct iovec *vec = &iov[seg]; >> - result = nfs_direct_write_schedule_segment(&desc, vec, >> pos, uio); >> - if (result < 0) >> - break; >> - requested_bytes += result; >> - if ((size_t)result < vec->iov_len) >> - break; >> - pos += vec->iov_len; >> - } >> + NFS_I(dreq->inode)->write_io += iov_iter_count(iter); >> + >> + if (iov_iter_has_iovec(iter)) { >> + const struct iovec *iov = iov_iter_iovec(iter); >> + for (seg = 0; seg < iter->nr_segs; seg++) { >> + const struct iovec *vec = &iov[seg]; >> + result = nfs_direct_write_schedule_segment(&desc, >> vec, >> + pos, uio); >> + if (result < 0) >> + break; >> + requested_bytes += result; >> + if ((size_t)result < vec->iov_len) >> + break; >> + pos += vec->iov_len; >> + } >> + } else if (iov_iter_has_bvec(iter)) { >> + struct nfs_open_context *ctx = dreq->ctx; >> + struct bio_vec *bvec = iov_iter_bvec(iter); >> + for (seg = 0; seg < iter->nr_segs; seg++) { >> + struct nfs_page *req; >> + unsigned int req_len = bvec[seg].bv_len; >> + >> + req = nfs_create_request(ctx, inode, >> bvec[seg].bv_page, >> + bvec[seg].bv_offset, >> req_len); >> + if (IS_ERR(req)) { >> + result = PTR_ERR(req); >> + break; >> + } >> + nfs_lock_request(req); >> + req->wb_index = pos >> PAGE_SHIFT; >> + req->wb_offset = pos & ~PAGE_MASK; >> + if (!nfs_pageio_add_request(&desc, req)) { >> + result = desc.pg_error; >> + nfs_unlock_and_release_request(req); >> + break; >> + } >> + requested_bytes += req_len; >> + pos += req_len; >> + } >> + } else >> + BUG(); > > Ditto... ok > > Otherwise, everything looks fine to me... > > Acked-by: Trond Myklebust <Trond.Myklebust@xxxxxxxxxx> > > Cheers > Trond Thanks, Shaggy -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
