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2022-10-07kunit: make kunit_kfree(NULL) a no-op to match kfree()Daniel Latypov
The real kfree() function will silently return when given a NULL. So a user might reasonably think they can write the following code: char *buffer = NULL; if (param->use_buffer) buffer = kunit_kzalloc(test, 10, GFP_KERNEL); ... kunit_kfree(test, buffer); As-is, kunit_kfree() will mark the test as FAILED when buffer is NULL. (And in earlier times, it would segfault). Let's match the semantics of kfree(). Suggested-by: David Gow <davidgow@google.com> Signed-off-by: Daniel Latypov <dlatypov@google.com> Reviewed-by: David Gow <davidgow@google.com> Reviewed-by: Brendan Higgins <brendanhiggins@google.com> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2022-10-07kunit: make kunit_kfree() not segfault on invalid inputsDaniel Latypov
kunit_kfree() can only work on data ("resources") allocated by KUnit. Currently for code like this, > void *ptr = kmalloc(4, GFP_KERNEL); > kunit_kfree(test, ptr); kunit_kfree() will segfault. It'll try and look up the kunit_resource associated with `ptr` and get a NULL back, but it won't check for this. This means we also segfault if you double-free. Change kunit_kfree() so it'll notice these invalid pointers and respond by failing the test. Implementation: kunit_destroy_resource() does what kunit_kfree() does, but is more generic and returns -ENOENT when it can't find the resource. Sadly, unlike just letting it crash, this means we don't get a stack trace. But kunit_kfree() is so infrequently used it shouldn't be hard to track down the bad callsite anyways. After this change, the above code gives: > # example_simple_test: EXPECTATION FAILED at lib/kunit/test.c:702 > kunit_kfree: 00000000626ec200 already freed or not allocated by kunit Signed-off-by: Daniel Latypov <dlatypov@google.com> Reviewed-by: David Gow <davidgow@google.com> Reviewed-by: Brendan Higgins <brendanhiggins@google.com> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2022-10-07kunit: make kunit_kfree() only work on pointers from kunit_malloc() and friendsDaniel Latypov
kunit_kfree() exists to clean up allocations from kunit_kmalloc() and friends early instead of waiting for this to happen automatically at the end of the test. But it can be used on *anything* registered with the kunit resource API. E.g. the last 2 statements are equivalent: struct kunit_resource *res = something(); kfree(res->data); kunit_put_resource(res); The problem is that there could be multiple resources that point to the same `data`. E.g. you can have a named resource acting as a pseudo-global variable in a test. If you point it to data allocated with kunit_kmalloc(), then calling `kunit_kfree(ptr)` has the chance to delete either the named resource or to kfree `ptr`. Which one it does depends on the order the resources are registered as kunit_kfree() will delete resources in LIFO order. So this patch restricts kunit_kfree() to only working on resources created by kunit_kmalloc(). Calling it is therefore guaranteed to free the memory, not do anything else. Note: kunit_resource_instance_match() wasn't used outside of KUnit, so it should be safe to remove from the public interface. It's also generally dangerous, as shown above, and shouldn't be used. Signed-off-by: Daniel Latypov <dlatypov@google.com> Reviewed-by: David Gow <davidgow@google.com> Reviewed-by: Brendan Higgins <brendanhiggins@google.com> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2022-10-07kunit: drop test pointer in string_stream_fragmentDaniel Latypov
We already store the `struct kunit *test` in the string_stream object itself, so we need don't need to store a copy of this pointer in every fragment in the stream. Drop it, getting string_stream_fragment down the bare minimum: a list_head and the `char *` with the actual fragment. Signed-off-by: Daniel Latypov <dlatypov@google.com> Reviewed-by: David Gow <davidgow@google.com> Reviewed-by: Brendan Higgins <brendanhiggins@google.com> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2022-10-07kunit: string-stream: Simplify resource useDavid Gow
Currently, KUnit's string streams are themselves "KUnit resources". This is redundant since the stream itself is already allocated with kunit_kzalloc() and will thus be freed automatically at the end of the test. string-stream is only used internally within KUnit, and isn't using the extra features that resources provide like reference counting, being able to locate them dynamically as "test-local variables", etc. Indeed, the resource's refcount is never incremented when the pointer is returned. The fact that it's always manually destroyed is more evidence that the reference counting is unused. Signed-off-by: David Gow <davidgow@google.com> Signed-off-by: Daniel Latypov <dlatypov@google.com> Reviewed-by: Brendan Higgins <brendanhiggins@google.com> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2022-09-30lib: stackinit: update reference to kunit-toolTales Aparecida
Replace URL with an updated path to the full Documentation page Signed-off-by: Tales Aparecida <tales.aparecida@gmail.com> Reviewed-by: David Gow <davidgow@google.com> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2022-09-30lib: overflow: update reference to kunit-toolTales Aparecida
Replace URL with an updated path to the full Documentation page Signed-off-by: Tales Aparecida <tales.aparecida@gmail.com> Reviewed-by: Kees Cook <keescook@chromium.org> Reviewed-by: David Gow <davidgow@google.com> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2022-09-30kunit: add kunit.enable to enable/disable KUnit testJoe Fradley
This patch adds the kunit.enable module parameter that will need to be set to true in addition to KUNIT being enabled for KUnit tests to run. The default value is true giving backwards compatibility. However, for the production+testing use case the new config option KUNIT_DEFAULT_ENABLED can be set to N requiring the tester to opt-in by passing kunit.enable=1 to the kernel. Signed-off-by: Joe Fradley <joefradley@google.com> Reviewed-by: David Gow <davidgow@google.com> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2022-09-24Makefile.debug: re-enable debug info for .S filesNick Desaulniers
Alexey reported that the fraction of unknown filename instances in kallsyms grew from ~0.3% to ~10% recently; Bill and Greg tracked it down to assembler defined symbols, which regressed as a result of: commit b8a9092330da ("Kbuild: do not emit debug info for assembly with LLVM_IAS=1") In that commit, I allude to restoring debug info for assembler defined symbols in a follow up patch, but it seems I forgot to do so in commit a66049e2cf0e ("Kbuild: make DWARF version a choice") Link: https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=31bf18645d98b4d3d7357353be840e320649a67d Fixes: b8a9092330da ("Kbuild: do not emit debug info for assembly with LLVM_IAS=1") Reported-by: Alexey Alexandrov <aalexand@google.com> Reported-by: Bill Wendling <morbo@google.com> Reported-by: Greg Thelen <gthelen@google.com> Reviewed-by: Nathan Chancellor <nathan@kernel.org> Suggested-by: Masahiro Yamada <masahiroy@kernel.org> Signed-off-by: Nick Desaulniers <ndesaulniers@google.com> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2022-08-31Merge tag 'v6.0-p2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 Pull crypto fix from Herbert Xu: "Fix a boot performance regression due to an unnecessary dependency on XOR_BLOCKS" * tag 'v6.0-p2' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: crypto: lib - remove unneeded selection of XOR_BLOCKS
2022-08-28Merge tag 'bitmap-6.0-rc3' of github.com:/norov/linuxLinus Torvalds
Pull bitmap fixes from Yury Norov: "Fix the reported issues, and implements the suggested improvements, for the version of the cpumask tests [1] that was merged with commit c41e8866c28c ("lib/test: introduce cpumask KUnit test suite"). These changes include fixes for the tests, and better alignment with the KUnit style guidelines" * tag 'bitmap-6.0-rc3' of github.com:/norov/linux: lib/cpumask_kunit: add tests file to MAINTAINERS lib/cpumask_kunit: log mask contents lib/test_cpumask: follow KUnit style guidelines lib/test_cpumask: fix cpu_possible_mask last test lib/test_cpumask: drop cpu_possible_mask full test
2022-08-26crypto: lib - remove unneeded selection of XOR_BLOCKSEric Biggers
CRYPTO_LIB_CHACHA_GENERIC doesn't need to select XOR_BLOCKS. It perhaps was thought that it's needed for __crypto_xor, but that's not the case. Enabling XOR_BLOCKS is problematic because the XOR_BLOCKS code runs a benchmark when it is initialized. That causes a boot time regression on systems that didn't have it enabled before. Therefore, remove this unnecessary and problematic selection. Fixes: e56e18985596 ("lib/crypto: add prompts back to crypto libraries") Cc: stable@vger.kernel.org Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2022-08-25Merge tag 'net-6.0-rc3' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net Pull networking fixes from Jakub Kicinski: "Including fixes from ipsec and netfilter (with one broken Fixes tag). Current release - new code bugs: - dsa: don't dereference NULL extack in dsa_slave_changeupper() - dpaa: fix <1G ethernet on LS1046ARDB - neigh: don't call kfree_skb() under spin_lock_irqsave() Previous releases - regressions: - r8152: fix the RX FIFO settings when suspending - dsa: microchip: keep compatibility with device tree blobs with no phy-mode - Revert "net: macsec: update SCI upon MAC address change." - Revert "xfrm: update SA curlft.use_time", comply with RFC 2367 Previous releases - always broken: - netfilter: conntrack: work around exceeded TCP receive window - ipsec: fix a null pointer dereference of dst->dev on a metadata dst in xfrm_lookup_with_ifid - moxa: get rid of asymmetry in DMA mapping/unmapping - dsa: microchip: make learning configurable and keep it off while standalone - ice: xsk: prohibit usage of non-balanced queue id - rxrpc: fix locking in rxrpc's sendmsg Misc: - another chunk of sysctl data race silencing" * tag 'net-6.0-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (87 commits) net: lantiq_xrx200: restore buffer if memory allocation failed net: lantiq_xrx200: fix lock under memory pressure net: lantiq_xrx200: confirm skb is allocated before using net: stmmac: work around sporadic tx issue on link-up ionic: VF initial random MAC address if no assigned mac ionic: fix up issues with handling EAGAIN on FW cmds ionic: clear broken state on generation change rxrpc: Fix locking in rxrpc's sendmsg net: ethernet: mtk_eth_soc: fix hw hash reporting for MTK_NETSYS_V2 MAINTAINERS: rectify file entry in BONDING DRIVER i40e: Fix incorrect address type for IPv6 flow rules ixgbe: stop resetting SYSTIME in ixgbe_ptp_start_cyclecounter net: Fix a data-race around sysctl_somaxconn. net: Fix a data-race around netdev_unregister_timeout_secs. net: Fix a data-race around gro_normal_batch. net: Fix data-races around sysctl_devconf_inherit_init_net. net: Fix data-races around sysctl_fb_tunnels_only_for_init_net. net: Fix a data-race around netdev_budget_usecs. net: Fix data-races around sysctl_max_skb_frags. net: Fix a data-race around netdev_budget. ...
2022-08-24lib/cpumask_kunit: log mask contentsSander Vanheule
For extra context, log the contents of the masks under test. This should help with finding out why a certain test fails. Link: https://lore.kernel.org/lkml/CABVgOSkPXBc-PWk1zBZRQ_Tt+Sz1ruFHBj3ixojymZF=Vi4tpQ@mail.gmail.com/ Suggested-by: David Gow <davidgow@google.com> Signed-off-by: Sander Vanheule <sander@svanheule.net> Signed-off-by: Yury Norov <yury.norov@gmail.com>
2022-08-24lib/test_cpumask: follow KUnit style guidelinesSander Vanheule
The cpumask test suite doesn't follow the KUnit style guidelines, as laid out in Documentation/dev-tools/kunit/style.rst. The file is renamed to lib/cpumask_kunit.c to clearly distinguish it from other, non-KUnit, tests. Link: https://lore.kernel.org/lkml/346cb279-8e75-24b0-7d12-9803f2b41c73@riseup.net/ Suggested-by: Maíra Canal <mairacanal@riseup.net> Signed-off-by: Sander Vanheule <sander@svanheule.net> Reviewed-by: Maíra Canal <mairacanal@riseup.net> Reviewed-by: David Gow <davidgow@google.com> Acked-by: Yury Norov <yury.norov@gmail.com> Signed-off-by: Yury Norov <yury.norov@gmail.com>
2022-08-24lib/test_cpumask: fix cpu_possible_mask last testSander Vanheule
Since cpumask_first() on the cpu_possible_mask must return at most nr_cpu_ids - 1 for a valid result, cpumask_last() cannot return anything larger than this value. As test_cpumask_weight() also verifies that the total weight of cpu_possible_mask must equal nr_cpu_ids, the last bit set in this mask must be at nr_cpu_ids - 1. Fixes: c41e8866c28c ("lib/test: introduce cpumask KUnit test suite") Link: https://lore.kernel.org/lkml/346cb279-8e75-24b0-7d12-9803f2b41c73@riseup.net/ Reported-by: Maíra Canal <mairacanal@riseup.net> Signed-off-by: Sander Vanheule <sander@svanheule.net> Tested-by: Maíra Canal <mairacanal@riseup.net> Reviewed-by: David Gow <davidgow@google.com> Acked-by: Yury Norov <yury.norov@gmail.com> Signed-off-by: Yury Norov <yury.norov@gmail.com>
2022-08-24lib/test_cpumask: drop cpu_possible_mask full testSander Vanheule
When the number of CPUs that can possibly be brought online is known at boot time, e.g. when HOTPLUG is disabled, nr_cpu_ids may be smaller than NR_CPUS. In that case, cpu_possible_mask would not be completely filled, and cpumask_full(cpu_possible_mask) can return false for valid system configurations. Without this test, cpu_possible_mask contents are still constrained by a check on cpumask_weight(), as well as tests in test_cpumask_first(), test_cpumask_last(), test_cpumask_next(), and test_cpumask_iterators(). Fixes: c41e8866c28c ("lib/test: introduce cpumask KUnit test suite") Link: https://lore.kernel.org/lkml/346cb279-8e75-24b0-7d12-9803f2b41c73@riseup.net/ Reported-by: Maíra Canal <mairacanal@riseup.net> Signed-off-by: Sander Vanheule <sander@svanheule.net> Tested-by: Maíra Canal <mairacanal@riseup.net> Reviewed-by: David Gow <davidgow@google.com> Signed-off-by: Yury Norov <yury.norov@gmail.com>
2022-08-24ratelimit: Fix data-races in ___ratelimit().Kuniyuki Iwashima
While reading rs->interval and rs->burst, they can be changed concurrently via sysctl (e.g. net_ratelimit_state). Thus, we need to add READ_ONCE() to their readers. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-08-15lib/cpumask: drop always-true preprocessor guardSander Vanheule
Since lib/cpumask.o is only built for CONFIG_SMP=y, NR_CPUS will always be greater than 1 at compile time. This makes checking for that condition unnecesarry, so it can be dropped. Signed-off-by: Sander Vanheule <sander@svanheule.net> Signed-off-by: Yury Norov <yury.norov@gmail.com>
2022-08-15lib/cpumask: add inline cpumask_next_wrap() for UPSander Vanheule
In the uniprocessor case, cpumask_next_wrap() can be simplified, as the number of valid argument combinations is limited: - 'start' can only be 0 - 'n' can only be -1 or 0 The only valid CPU that can then be returned, if any, will be the first one set in the provided 'mask'. For NR_CPUS == 1, include/linux/cpumask.h now provides an inline definition of cpumask_next_wrap(), which will conflict with the one provided by lib/cpumask.c. Make building of lib/cpumask.o again depend on CONFIG_SMP=y (i.e. NR_CPUS > 1) to avoid the re-definition. Suggested-by: Yury Norov <yury.norov@gmail.com> Signed-off-by: Sander Vanheule <sander@svanheule.net> Signed-off-by: Yury Norov <yury.norov@gmail.com>
2022-08-12lib: remove lib/nodemask.cYury Norov
Commit 36d4b36b6959 ("lib/nodemask: inline next_node_in() and node_random()") removed the lib/nodemask.c file, but the remove didn't happen when the patch was applied. Reported-by: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com> Signed-off-by: Yury Norov <yury.norov@gmail.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-08-08Merge tag 'pull-work.iov_iter-rebased' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull more iov_iter updates from Al Viro: - more new_sync_{read,write}() speedups - ITER_UBUF introduction - ITER_PIPE cleanups - unification of iov_iter_get_pages/iov_iter_get_pages_alloc and switching them to advancing semantics - making ITER_PIPE take high-order pages without splitting them - handling copy_page_from_iter() for high-order pages properly * tag 'pull-work.iov_iter-rebased' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (32 commits) fix copy_page_from_iter() for compound destinations hugetlbfs: copy_page_to_iter() can deal with compound pages copy_page_to_iter(): don't split high-order page in case of ITER_PIPE expand those iov_iter_advance()... pipe_get_pages(): switch to append_pipe() get rid of non-advancing variants ceph: switch the last caller of iov_iter_get_pages_alloc() 9p: convert to advancing variant of iov_iter_get_pages_alloc() af_alg_make_sg(): switch to advancing variant of iov_iter_get_pages() iter_to_pipe(): switch to advancing variant of iov_iter_get_pages() block: convert to advancing variants of iov_iter_get_pages{,_alloc}() iov_iter: advancing variants of iov_iter_get_pages{,_alloc}() iov_iter: saner helper for page array allocation fold __pipe_get_pages() into pipe_get_pages() ITER_XARRAY: don't open-code DIV_ROUND_UP() unify the rest of iov_iter_get_pages()/iov_iter_get_pages_alloc() guts unify xarray_get_pages() and xarray_get_pages_alloc() unify pipe_get_pages() and pipe_get_pages_alloc() iov_iter_get_pages(): sanity-check arguments iov_iter_get_pages_alloc(): lift freeing pages array on failure exits into wrapper ...
2022-08-08fix copy_page_from_iter() for compound destinationsAl Viro
had been broken for ITER_BVEC et.al. since ever (OK, v3.17 when ITER_BVEC had first appeared)... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2022-08-08copy_page_to_iter(): don't split high-order page in case of ITER_PIPEAl Viro
... just shove it into one pipe_buffer. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2022-08-08expand those iov_iter_advance()...Al Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2022-08-08pipe_get_pages(): switch to append_pipe()Al Viro
now that we are advancing the iterator, there's no need to treat the first page separately - just call append_pipe() in a loop. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2022-08-08get rid of non-advancing variantsAl Viro
mechanical change; will be further massaged in subsequent commits Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2022-08-08iov_iter: saner helper for page array allocationAl Viro
All call sites of get_pages_array() are essenitally identical now. Replace with common helper... Returns number of slots available in resulting array or 0 on OOM; it's up to the caller to make sure it doesn't ask to zero-entry array (i.e. neither maxpages nor size are allowed to be zero). Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2022-08-08fold __pipe_get_pages() into pipe_get_pages()Al Viro
... and don't mangle maxsize there - turn the loop into counting one instead. Easier to see that we won't run out of array that way. Note that special treatment of the partial buffer in that thing is an artifact of the non-advancing semantics of iov_iter_get_pages() - if not for that, it would be append_pipe(), same as the body of the loop that follows it. IOW, once we make iov_iter_get_pages() advancing, the whole thing will turn into calculate how many pages do we want allocate an array (if needed) call append_pipe() that many times. Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2022-08-08ITER_XARRAY: don't open-code DIV_ROUND_UP()Al Viro
Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2022-08-08unify the rest of iov_iter_get_pages()/iov_iter_get_pages_alloc() gutsAl Viro
same as for pipes and xarrays; after that iov_iter_get_pages() becomes a wrapper for __iov_iter_get_pages_alloc(). Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2022-08-08unify xarray_get_pages() and xarray_get_pages_alloc()Al Viro
same as for pipes Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2022-08-08unify pipe_get_pages() and pipe_get_pages_alloc()Al Viro
The differences between those two are * pipe_get_pages() gets a non-NULL struct page ** value pointing to preallocated array + array size. * pipe_get_pages_alloc() gets an address of struct page ** variable that contains NULL, allocates the array and (on success) stores its address in that variable. Not hard to combine - always pass struct page ***, have the previous pipe_get_pages_alloc() caller pass ~0U as cap for array size. Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2022-08-08iov_iter_get_pages(): sanity-check argumentsAl Viro
zero maxpages is bogus, but best treated as "just return 0"; NULL pages, OTOH, should be treated as a hard bug. get rid of now completely useless checks in xarray_get_pages{,_alloc}(). Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2022-08-08iov_iter_get_pages_alloc(): lift freeing pages array on failure exits into ↵Al Viro
wrapper Incidentally, ITER_XARRAY did *not* free the sucker in case when iter_xarray_populate_pages() returned 0... Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2022-08-08ITER_PIPE: fold data_start() and pipe_space_for_user() togetherAl Viro
All their callers are next to each other; all of them want the total amount of pages and, possibly, the offset in the partial final buffer. Combine into a new helper (pipe_npages()), fix the bogosity in pipe_space_for_user(), while we are at it. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2022-08-08ITER_PIPE: cache the type of last bufferAl Viro
We often need to find whether the last buffer is anon or not, and currently it's rather clumsy: check if ->iov_offset is non-zero (i.e. that pipe is not empty) if so, get the corresponding pipe_buffer and check its ->ops if it's &default_pipe_buf_ops, we have an anon buffer. Let's replace the use of ->iov_offset (which is nowhere near similar to its role for other flavours) with signed field (->last_offset), with the following rules: empty, no buffers occupied: 0 anon, with bytes up to N-1 filled: N zero-copy, with bytes up to N-1 filled: -N That way abs(i->last_offset) is equal to what used to be in i->iov_offset and empty vs. anon vs. zero-copy can be distinguished by the sign of i->last_offset. Checks for "should we extend the last buffer or should we start a new one?" become easier to follow that way. Note that most of the operations can only be done in a sane state - i.e. when the pipe has nothing past the current position of iterator. About the only thing that could be done outside of that state is iov_iter_advance(), which transitions to the sane state by truncating the pipe. There are only two cases where we leave the sane state: 1) iov_iter_get_pages()/iov_iter_get_pages_alloc(). Will be dealt with later, when we make get_pages advancing - the callers are actually happier that way. 2) iov_iter copied, then something is put into the copy. Since they share the underlying pipe, the original gets behind. When we decide that we are done with the copy (original is not usable until then) we advance the original. direct_io used to be done that way; nowadays it operates on the original and we do iov_iter_revert() to discard the excessive data. At the moment there's nothing in the kernel that could do that to ITER_PIPE iterators, so this reason for insane state is theoretical right now. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2022-08-08ITER_PIPE: clean iov_iter_revert()Al Viro
Fold pipe_truncate() into it, clean up. We can release buffers in the same loop where we walk backwards to the iterator beginning looking for the place where the new position will be. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2022-08-08ITER_PIPE: clean pipe_advance() upAl Viro
instead of setting ->iov_offset for new position and calling pipe_truncate() to adjust ->len of the last buffer and discard everything after it, adjust ->len at the same time we set ->iov_offset and use pipe_discard_from() to deal with buffers past that. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2022-08-08ITER_PIPE: lose iter_head argument of __pipe_get_pages()Al Viro
it's only used to get to the partial buffer we can add to, and that's always the last one, i.e. pipe->head - 1. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2022-08-08ITER_PIPE: fold push_pipe() into __pipe_get_pages()Al Viro
Expand the only remaining call of push_pipe() (in __pipe_get_pages()), combine it with the page-collecting loop there. Note that the only reason it's not a loop doing append_pipe() is that append_pipe() is advancing, while iov_iter_get_pages() is not. As soon as it switches to saner semantics, this thing will switch to using append_pipe(). Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2022-08-08ITER_PIPE: allocate buffers as we go in copy-to-pipe primitivesAl Viro
New helper: append_pipe(). Extends the last buffer if possible, allocates a new one otherwise. Returns page and offset in it on success, NULL on failure. iov_iter is advanced past the data we've got. Use that instead of push_pipe() in copy-to-pipe primitives; they get simpler that way. Handling of short copy (in "mc" one) is done simply by iov_iter_revert() - iov_iter is in consistent state after that one, so we can use that. [Fix for braino caught by Liu Xinpeng <liuxp11@chinatelecom.cn> folded in] [another braino fix, this time in copy_pipe_to_iter() and pipe_zero(); caught by testcase from Hugh Dickins] Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2022-08-08ITER_PIPE: helpers for adding pipe buffersAl Viro
There are only two kinds of pipe_buffer in the area used by ITER_PIPE. 1) anonymous - copy_to_iter() et.al. end up creating those and copying data there. They have zero ->offset, and their ->ops points to default_pipe_page_ops. 2) zero-copy ones - those come from copy_page_to_iter(), and page comes from caller. ->offset is also caller-supplied - it might be non-zero. ->ops points to page_cache_pipe_buf_ops. Move creation and insertion of those into helpers - push_anon(pipe, size) and push_page(pipe, page, offset, size) resp., separating them from the "could we avoid creating a new buffer by merging with the current head?" logics. Acked-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2022-08-08ITER_PIPE: helper for getting pipe buffer by indexAl Viro
pipe_buffer instances of a pipe are organized as a ring buffer, with power-of-2 size. Indices are kept *not* reduced modulo ring size, so the buffer refered to by index N is pipe->bufs[N & (pipe->ring_size - 1)]. Ring size can change over the lifetime of a pipe, but not while the pipe is locked. So for any iov_iter primitives it's a constant. Original conversion of pipes to this layout went overboard trying to microoptimize that - calculating pipe->ring_size - 1, storing it in a local variable and using through the function. In some cases it might be warranted, but most of the times it only obfuscates what's going on in there. Introduce a helper (pipe_buf(pipe, N)) that would encapsulate that and use it in the obvious cases. More will follow... Reviewed-by: Jeff Layton <jlayton@kernel.org> Reviewed-by: Christian Brauner (Microsoft) <brauner@kernel.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2022-08-08new iov_iter flavour - ITER_UBUFAl Viro
Equivalent of single-segment iovec. Initialized by iov_iter_ubuf(), checked for by iter_is_ubuf(), otherwise behaves like ITER_IOVEC ones. We are going to expose the things like ->write_iter() et.al. to those in subsequent commits. New predicate (user_backed_iter()) that is true for ITER_IOVEC and ITER_UBUF; places like direct-IO handling should use that for checking that pages we modify after getting them from iov_iter_get_pages() would need to be dirtied. DO NOT assume that replacing iter_is_iovec() with user_backed_iter() will solve all problems - there's code that uses iter_is_iovec() to decide how to poke around in iov_iter guts and for that the predicate replacement obviously won't suffice. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2022-08-07Merge tag 'bitmap-6.0-rc1' of https://github.com/norov/linuxLinus Torvalds
Pull bitmap updates from Yury Norov: - fix the duplicated comments on bitmap_to_arr64() (Qu Wenruo) - optimize out non-atomic bitops on compile-time constants (Alexander Lobakin) - cleanup bitmap-related headers (Yury Norov) - x86/olpc: fix 'logical not is only applied to the left hand side' (Alexander Lobakin) - lib/nodemask: inline wrappers around bitmap (Yury Norov) * tag 'bitmap-6.0-rc1' of https://github.com/norov/linux: (26 commits) lib/nodemask: inline next_node_in() and node_random() powerpc: drop dependency on <asm/machdep.h> in archrandom.h x86/olpc: fix 'logical not is only applied to the left hand side' lib/cpumask: move some one-line wrappers to header file headers/deps: mm: align MANITAINERS and Docs with new gfp.h structure headers/deps: mm: Split <linux/gfp_types.h> out of <linux/gfp.h> headers/deps: mm: Optimize <linux/gfp.h> header dependencies lib/cpumask: move trivial wrappers around find_bit to the header lib/cpumask: change return types to unsigned where appropriate cpumask: change return types to bool where appropriate lib/bitmap: change type of bitmap_weight to unsigned long lib/bitmap: change return types to bool where appropriate arm: align find_bit declarations with generic kernel iommu/vt-d: avoid invalid memory access via node_online(NUMA_NO_NODE) lib/test_bitmap: test the tail after bitmap_to_arr64() lib/bitmap: fix off-by-one in bitmap_to_arr64() lib: test_bitmap: add compile-time optimization/evaluations assertions bitmap: don't assume compiler evaluates small mem*() builtins calls net/ice: fix initializing the bitmap in the switch code bitops: let optimize out non-atomic bitops on compile-time constants ...
2022-08-07Merge tag 'mm-nonmm-stable-2022-08-06-2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull misc updates from Andrew Morton: "Updates to various subsystems which I help look after. lib, ocfs2, fatfs, autofs, squashfs, procfs, etc. A relatively small amount of material this time" * tag 'mm-nonmm-stable-2022-08-06-2' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (72 commits) scripts/gdb: ensure the absolute path is generated on initial source MAINTAINERS: kunit: add David Gow as a maintainer of KUnit mailmap: add linux.dev alias for Brendan Higgins mailmap: update Kirill's email profile: setup_profiling_timer() is moslty not implemented ocfs2: fix a typo in a comment ocfs2: use the bitmap API to simplify code ocfs2: remove some useless functions lib/mpi: fix typo 'the the' in comment proc: add some (hopefully) insightful comments bdi: remove enum wb_congested_state kernel/hung_task: fix address space of proc_dohung_task_timeout_secs lib/lzo/lzo1x_compress.c: replace ternary operator with min() and min_t() squashfs: support reading fragments in readahead call squashfs: implement readahead squashfs: always build "file direct" version of page actor Revert "squashfs: provide backing_dev_info in order to disable read-ahead" fs/ocfs2: Fix spelling typo in comment ia64: old_rr4 added under CONFIG_HUGETLB_PAGE proc: fix test for "vsyscall=xonly" boot option ...
2022-08-06Merge tag 'livepatching-for-5.20' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/livepatching/livepatching Pull livepatching update from Petr Mladek: - Make a selftest more reliable * tag 'livepatching-for-5.20' of git://git.kernel.org/pub/scm/linux/kernel/git/livepatching/livepatching: selftests/livepatch: better synchronize test_klp_callbacks_busy
2022-08-05Merge tag 'mm-stable-2022-08-03' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull MM updates from Andrew Morton: "Most of the MM queue. A few things are still pending. Liam's maple tree rework didn't make it. This has resulted in a few other minor patch series being held over for next time. Multi-gen LRU still isn't merged as we were waiting for mapletree to stabilize. The current plan is to merge MGLRU into -mm soon and to later reintroduce mapletree, with a view to hopefully getting both into 6.1-rc1. Summary: - The usual batches of cleanups from Baoquan He, Muchun Song, Miaohe Lin, Yang Shi, Anshuman Khandual and Mike Rapoport - Some kmemleak fixes from Patrick Wang and Waiman Long - DAMON updates from SeongJae Park - memcg debug/visibility work from Roman Gushchin - vmalloc speedup from Uladzislau Rezki - more folio conversion work from Matthew Wilcox - enhancements for coherent device memory mapping from Alex Sierra - addition of shared pages tracking and CoW support for fsdax, from Shiyang Ruan - hugetlb optimizations from Mike Kravetz - Mel Gorman has contributed some pagealloc changes to improve latency and realtime behaviour. - mprotect soft-dirty checking has been improved by Peter Xu - Many other singleton patches all over the place" [ XFS merge from hell as per Darrick Wong in https://lore.kernel.org/all/YshKnxb4VwXycPO8@magnolia/ ] * tag 'mm-stable-2022-08-03' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (282 commits) tools/testing/selftests/vm/hmm-tests.c: fix build mm: Kconfig: fix typo mm: memory-failure: convert to pr_fmt() mm: use is_zone_movable_page() helper hugetlbfs: fix inaccurate comment in hugetlbfs_statfs() hugetlbfs: cleanup some comments in inode.c hugetlbfs: remove unneeded header file hugetlbfs: remove unneeded hugetlbfs_ops forward declaration hugetlbfs: use helper macro SZ_1{K,M} mm: cleanup is_highmem() mm/hmm: add a test for cross device private faults selftests: add soft-dirty into run_vmtests.sh selftests: soft-dirty: add test for mprotect mm/mprotect: fix soft-dirty check in can_change_pte_writable() mm: memcontrol: fix potential oom_lock recursion deadlock mm/gup.c: fix formatting in check_and_migrate_movable_page() xfs: fail dax mount if reflink is enabled on a partition mm/memcontrol.c: remove the redundant updating of stats_flush_threshold userfaultfd: don't fail on unrecognized features hugetlb_cgroup: fix wrong hugetlb cgroup numa stat ...
2022-08-05Merge tag 'asm-generic-6.0' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic Pull asm-generic updates from Arnd Bergmann: "There are three independent sets of changes: - Sai Prakash Ranjan adds tracing support to the asm-generic version of the MMIO accessors, which is intended to help understand problems with device drivers and has been part of Qualcomm's vendor kernels for many years - A patch from Sebastian Siewior to rework the handling of IRQ stacks in softirqs across architectures, which is needed for enabling PREEMPT_RT - The last patch to remove the CONFIG_VIRT_TO_BUS option and some of the code behind that, after the last users of this old interface made it in through the netdev, scsi, media and staging trees" * tag 'asm-generic-6.0' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic: uapi: asm-generic: fcntl: Fix typo 'the the' in comment arch/*/: remove CONFIG_VIRT_TO_BUS soc: qcom: geni: Disable MMIO tracing for GENI SE serial: qcom_geni_serial: Disable MMIO tracing for geni serial asm-generic/io: Add logging support for MMIO accessors KVM: arm64: Add a flag to disable MMIO trace for nVHE KVM lib: Add register read/write tracing support drm/meson: Fix overflow implicit truncation warnings irqchip/tegra: Fix overflow implicit truncation warnings coresight: etm4x: Use asm-generic IO memory barriers arm64: io: Use asm-generic high level MMIO accessors arch/*: Disable softirq stacks on PREEMPT_RT.