diff options
author | David Howells <dhowells@redhat.com> | 2020-02-06 14:22:28 +0000 |
---|---|---|
committer | David Howells <dhowells@redhat.com> | 2021-04-23 10:17:27 +0100 |
commit | c450846461f88b8888d6f5c2a2aa63ab64864978 (patch) | |
tree | b16a044f70d48605e7c838ae854b03f7098511e7 /fs/afs/fsclient.c | |
parent | 05092755aab4b7f5ec7541144c32b0744eb8d136 (diff) | |
download | linux-c450846461f88b8888d6f5c2a2aa63ab64864978.tar.bz2 |
afs: Set up the iov_iter before calling afs_extract_data()
afs_extract_data() sets up a temporary iov_iter and passes it to AF_RXRPC
each time it is called to describe the remaining buffer to be filled.
Instead:
(1) Put an iterator in the afs_call struct.
(2) Set the iterator for each marshalling stage to load data into the
appropriate places. A number of convenience functions are provided to
this end (eg. afs_extract_to_buf()).
This iterator is then passed to afs_extract_data().
(3) Use the new ITER_XARRAY iterator when reading data to load directly
into the inode's pages without needing to create a list of them.
This will allow O_DIRECT calls to be supported in future patches.
Signed-off-by: David Howells <dhowells@redhat.com>
Tested-By: Marc Dionne <marc.dionne@auristor.com>
cc: linux-afs@lists.infradead.org
cc: linux-cachefs@redhat.com
cc: linux-fsdevel@vger.kernel.org
Link: https://lore.kernel.org/r/152898380012.11616.12094591785228251717.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/153685394431.14766.3178466345696987059.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/153999787395.866.11218209749223643998.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/154033911195.12041.3882700371848894587.stgit@warthog.procyon.org.uk/ # v2
Link: https://lore.kernel.org/r/158861250059.340223.1248231474865140653.stgit@warthog.procyon.org.uk/ # rfc
Link: https://lore.kernel.org/r/159465827399.1377938.11181327349704960046.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/160588533776.3465195.3612752083351956948.stgit@warthog.procyon.org.uk/ # rfc
Link: https://lore.kernel.org/r/161118151238.1232039.17015723405750601161.stgit@warthog.procyon.org.uk/ # rfc
Link: https://lore.kernel.org/r/161161047240.2537118.14721975104810564022.stgit@warthog.procyon.org.uk/ # v2
Link: https://lore.kernel.org/r/161340410333.1303470.16260122230371140878.stgit@warthog.procyon.org.uk/ # v3
Link: https://lore.kernel.org/r/161539554187.286939.15305559004905459852.stgit@warthog.procyon.org.uk/ # v4
Link: https://lore.kernel.org/r/161653810525.2770958.4630666029125411789.stgit@warthog.procyon.org.uk/ # v5
Link: https://lore.kernel.org/r/161789093719.6155.7877160739235087723.stgit@warthog.procyon.org.uk/ # v6
Diffstat (limited to 'fs/afs/fsclient.c')
-rw-r--r-- | fs/afs/fsclient.c | 54 |
1 files changed, 14 insertions, 40 deletions
diff --git a/fs/afs/fsclient.c b/fs/afs/fsclient.c index 4a57c6c6f12b..897b37301851 100644 --- a/fs/afs/fsclient.c +++ b/fs/afs/fsclient.c @@ -302,7 +302,6 @@ static int afs_deliver_fs_fetch_data(struct afs_call *call) struct afs_vnode_param *vp = &op->file[0]; struct afs_read *req = op->fetch.req; const __be32 *bp; - unsigned int size; int ret; _enter("{%u,%zu,%zu/%llu}", @@ -312,8 +311,6 @@ static int afs_deliver_fs_fetch_data(struct afs_call *call) switch (call->unmarshall) { case 0: req->actual_len = 0; - req->index = 0; - req->offset = req->pos & (PAGE_SIZE - 1); call->unmarshall++; if (call->operation_ID == FSFETCHDATA64) { afs_extract_to_tmp64(call); @@ -323,7 +320,10 @@ static int afs_deliver_fs_fetch_data(struct afs_call *call) } fallthrough; - /* extract the returned data length */ + /* Extract the returned data length into + * ->actual_len. This may indicate more or less data than was + * requested will be returned. + */ case 1: _debug("extract data length"); ret = afs_extract_data(call, true); @@ -332,45 +332,25 @@ static int afs_deliver_fs_fetch_data(struct afs_call *call) req->actual_len = be64_to_cpu(call->tmp64); _debug("DATA length: %llu", req->actual_len); - req->remain = min(req->len, req->actual_len); - if (req->remain == 0) + + if (req->actual_len == 0) goto no_more_data; + call->iter = req->iter; + call->iov_len = min(req->actual_len, req->len); call->unmarshall++; - - begin_page: - ASSERTCMP(req->index, <, req->nr_pages); - if (req->remain > PAGE_SIZE - req->offset) - size = PAGE_SIZE - req->offset; - else - size = req->remain; - call->iov_len = size; - call->bvec[0].bv_len = size; - call->bvec[0].bv_offset = req->offset; - call->bvec[0].bv_page = req->pages[req->index]; - iov_iter_bvec(&call->def_iter, READ, call->bvec, 1, size); - ASSERTCMP(size, <=, PAGE_SIZE); fallthrough; /* extract the returned data */ case 2: _debug("extract data %zu/%llu", - iov_iter_count(call->iter), req->remain); + iov_iter_count(call->iter), req->actual_len); ret = afs_extract_data(call, true); if (ret < 0) return ret; - req->remain -= call->bvec[0].bv_len; - req->offset += call->bvec[0].bv_len; - ASSERTCMP(req->offset, <=, PAGE_SIZE); - if (req->offset == PAGE_SIZE) { - req->offset = 0; - req->index++; - if (req->remain > 0) - goto begin_page; - } - ASSERTCMP(req->remain, ==, 0); + call->iter = &call->def_iter; if (req->actual_len <= req->len) goto no_more_data; @@ -412,16 +392,8 @@ static int afs_deliver_fs_fetch_data(struct afs_call *call) break; } - for (; req->index < req->nr_pages; req->index++) { - if (req->offset < PAGE_SIZE) - zero_user_segment(req->pages[req->index], - req->offset, PAGE_SIZE); - req->offset = 0; - } - - if (req->page_done) - for (req->index = 0; req->index < req->nr_pages; req->index++) - req->page_done(req); + if (req->done) + req->done(req); _leave(" = 0 [done]"); return 0; @@ -496,6 +468,8 @@ void afs_fs_fetch_data(struct afs_operation *op) if (!call) return afs_op_nomem(op); + req->call_debug_id = call->debug_id; + /* marshall the parameters */ bp = call->request; bp[0] = htonl(FSFETCHDATA); |