kernel.git/net/sunrpc/xdr.c, branch linux-4.6.y

mm, fs: remove remaining PAGE_CACHE_* and page_cache_{get,release} usage

2016-04-04T17:41:08Z

Mostly direct substitution with occasional adjustment or removing outdated comments. Signed-off-by: Kirill A. Shutemov Acked-by: Michal Hocko Signed-off-by: Linus Torvalds

mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macros

2016-04-04T17:41:08Z

PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time ago with promise that one day it will be possible to implement page cache with bigger chunks than PAGE_SIZE. This promise never materialized. And unlikely will. We have many places where PAGE_CACHE_SIZE assumed to be equal to PAGE_SIZE. And it's constant source of confusion on whether PAGE_CACHE_* or PAGE_* constant should be used in a particular case, especially on the border between fs and mm. Global switching to PAGE_CACHE_SIZE != PAGE_SIZE would cause to much breakage to be doable. Let's stop pretending that pages in page cache are special. They are not. The changes are pretty straight-forward: - << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> ; - >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> ; - PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} -> PAGE_{SIZE,SHIFT,MASK,ALIGN}; - page_cache_get() -> get_page(); - page_cache_release() -> put_page(); This patch contains automated changes generated with coccinelle using script below. For some reason, coccinelle doesn't patch header files. I've called spatch for them manually. The only adjustment after coccinelle is revert of changes to PAGE_CAHCE_ALIGN definition: we are going to drop it later. There are few places in the code where coccinelle didn't reach. I'll fix them manually in a separate patch. Comments and documentation also will be addressed with the separate patch. virtual patch @@ expression E; @@ - E << (PAGE_CACHE_SHIFT - PAGE_SHIFT) + E @@ expression E; @@ - E >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) + E @@ @@ - PAGE_CACHE_SHIFT + PAGE_SHIFT @@ @@ - PAGE_CACHE_SIZE + PAGE_SIZE @@ @@ - PAGE_CACHE_MASK + PAGE_MASK @@ expression E; @@ - PAGE_CACHE_ALIGN(E) + PAGE_ALIGN(E) @@ expression E; @@ - page_cache_get(E) + get_page(E) @@ expression E; @@ - page_cache_release(E) + put_page(E) Signed-off-by: Kirill A. Shutemov Acked-by: Michal Hocko Signed-off-by: Linus Torvalds

rpc: fix xdr_truncate_encode to handle buffer ending on page boundary

2015-01-07T19:03:58Z

A struct xdr_stream at a page boundary might point to the end of one page or the beginning of the next, but xdr_truncate_encode isn't prepared to handle the former. This can cause corruption of NFSv4 READDIR replies in the case that a readdir entry that would have exceeded the client's dircount/maxcount limit would have ended exactly on a 4k page boundary. You're more likely to hit this case on large directories. Other xdr_truncate_encode callers are probably also affected. Reported-by: Holger Hoffstätte Tested-by: Holger Hoffstätte Fixes: 3e19ce762b53 "rpc: xdr_truncate_encode" Cc: stable@vger.kernel.org Signed-off-by: J. Bruce Fields

rpc: change comments to assertions

2014-10-23T18:05:11Z

Reported-by: Andrea Arcangeli Signed-off-by: J. Bruce Fields

RPC: remove unneeded checks from xdr_truncate_encode()

2014-10-23T18:05:11Z

Thanks to Andrea Arcangeli for pointing out these checks are obviously unnecessary given the preceding calculations. Reported-by: Andrea Arcangeli Signed-off-by: J. Bruce Fields

SUNRPC: xdr_get_next_encode_buffer should be declared static

2014-07-18T15:35:46Z

Quell another sparse warning. Signed-off-by: Trond Myklebust Signed-off-by: J. Bruce Fields

nfsd4: simplify server xdr->next_page use

2014-06-06T23:22:46Z

The rpc code makes available to the NFS server an array of pages to encod into. The server represents its reply as an xdr buf, with the head pointing into the first page in that array, the pages ** array starting just after that, and the tail (if any) sharing any leftover space in the page used by the head. While encoding, we use xdr_stream->page_ptr to keep track of which page we're currently using. Currently we set xdr_stream->page_ptr to buf->pages, which makes the head a weird exception to the rule that page_ptr always points to the page we're currently encoding into. So, instead set it to buf->pages - 1 (the page actually containing the head), and remove the need for a little unintuitive logic in xdr_get_next_encode_buffer() and xdr_truncate_encode. Signed-off-by: J. Bruce Fields

rpc: define xdr_restrict_buflen

2014-05-30T21:32:01Z

With this xdr_reserve_space can help us enforce various limits. Signed-off-by: J. Bruce Fields

nfsd4: allow encoding across page boundaries

2014-05-30T21:31:54Z

After this we can handle for example getattr of very large ACLs. Read, readdir, readlink are still special cases with their own limits. Also we can't handle a new operation starting close to the end of a page. Signed-off-by: J. Bruce Fields

rpc: xdr_truncate_encode

2014-05-30T21:31:47Z

This will be used in the server side in a few cases: - when certain operations (read, readdir, readlink) fail after encoding a partial response. - when we run out of space after encoding a partial response. - in readlink, where we initially reserve PAGE_SIZE bytes for data, then truncate to the actual size. Signed-off-by: J. Bruce Fields