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tools include UAPI: Sync linux/fcntl.h copy with the kernel sources
Picking the changes from: 4356d57 ("fhandle: expose u64 mount id to name_to_handle_at(2)") b4fef22 ("uapi: explain how per-syscall AT_* flags should be allocated") 820a185 ("fcntl: add F_CREATED_QUERY") It just moves AT_REMOVEDIR around, and adds a bunch more AT_ for renameat2() and name_to_handle_at(). We need to improve this situation, as not all AT_ defines are applicable to all fs flags... This adds support for those new AT_ defines, addressing this build warning: diff -u tools/perf/trace/beauty/include/uapi/sound/asound.h include/uapi/sound/asound.h Reviewed-by: Aleksa Sarai <cyphar@cyphar.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Christian Brauner <brauner@kernel.org> Cc: Ian Rogers <irogers@google.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Tejun Heo <tj@kernel.org> Link: https://lore.kernel.org/lkml/ZvrIKL3cREoRHIQd@x1 Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
1 parent 7ae76b3 commit 58f969b

2 files changed

Lines changed: 65 additions & 24 deletions

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‎tools/perf/trace/beauty/fs_at_flags.sh‎

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Original file line numberDiff line numberDiff line change
@@ -13,9 +13,14 @@ printf "static const char *fs_at_flags[] = {\n"
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regex='^[[:space:]]*#[[:space:]]*define[[:space:]]+AT_([^_]+[[:alnum:]_]+)[[:space:]]+(0x[[:xdigit:]]+)[[:space:]]*.*'
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# AT_EACCESS is only meaningful to faccessat, so we will special case it there...
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# AT_STATX_SYNC_TYPE is not a bit, its a mask of AT_STATX_SYNC_AS_STAT, AT_STATX_FORCE_SYNC and AT_STATX_DONT_SYNC
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# AT_HANDLE_FID and AT_HANDLE_MNT_ID_UNIQUE are reusing values and are valid only for name_to_handle_at()
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# AT_RENAME_NOREPLACE reuses 0x1 and is valid only for renameat2()
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grep -E $regex ${linux_fcntl} | \
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grep -v AT_EACCESS | \
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grep -v AT_STATX_SYNC_TYPE | \
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grep -v AT_HANDLE_FID | \
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grep -v AT_HANDLE_MNT_ID_UNIQUE | \
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grep -v AT_RENAME_NOREPLACE | \
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sed -r "s/$regex/\2 \1/g" | \
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xargs printf "\t[ilog2(%s) + 1] = \"%s\",\n"
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printf "};\n"

‎tools/perf/trace/beauty/include/uapi/linux/fcntl.h‎

Lines changed: 60 additions & 24 deletions
Original file line numberDiff line numberDiff line change
@@ -16,6 +16,9 @@
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#define F_DUPFD_QUERY (F_LINUX_SPECIFIC_BASE + 3)
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/* Was the file just created? */
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#define F_CREATED_QUERY (F_LINUX_SPECIFIC_BASE + 4)
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/*
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* Cancel a blocking posix lock; internal use only until we expose an
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* asynchronous lock api to userspace:
@@ -87,37 +90,70 @@
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#define DN_ATTRIB 0x00000020 /* File changed attibutes */
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#define DN_MULTISHOT 0x80000000 /* Don't remove notifier */
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#define AT_FDCWD -100 /* Special value for dirfd used to
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indicate openat should use the
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current working directory. */
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/* Generic flags for the *at(2) family of syscalls. */
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/* Reserved for per-syscall flags 0xff. */
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#define AT_SYMLINK_NOFOLLOW 0x100 /* Do not follow symbolic
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links. */
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/* Reserved for per-syscall flags 0x200 */
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#define AT_SYMLINK_FOLLOW 0x400 /* Follow symbolic links. */
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#define AT_NO_AUTOMOUNT 0x800 /* Suppress terminal automount
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traversal. */
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#define AT_EMPTY_PATH 0x1000 /* Allow empty relative
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pathname to operate on dirfd
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directly. */
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/*
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* These flags are currently statx(2)-specific, but they could be made generic
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* in the future and so they should not be used for other per-syscall flags.
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*/
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#define AT_STATX_SYNC_TYPE 0x6000 /* Type of synchronisation required from statx() */
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#define AT_STATX_SYNC_AS_STAT 0x0000 /* - Do whatever stat() does */
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#define AT_STATX_FORCE_SYNC 0x2000 /* - Force the attributes to be sync'd with the server */
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#define AT_STATX_DONT_SYNC 0x4000 /* - Don't sync attributes with the server */
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#define AT_RECURSIVE 0x8000 /* Apply to the entire subtree */
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/*
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* The constants AT_REMOVEDIR and AT_EACCESS have the same value. AT_EACCESS is
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* meaningful only to faccessat, while AT_REMOVEDIR is meaningful only to
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* unlinkat. The two functions do completely different things and therefore,
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* the flags can be allowed to overlap. For example, passing AT_REMOVEDIR to
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* faccessat would be undefined behavior and thus treating it equivalent to
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* AT_EACCESS is valid undefined behavior.
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* Per-syscall flags for the *at(2) family of syscalls.
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*
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* These are flags that are so syscall-specific that a user passing these flags
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* to the wrong syscall is so "clearly wrong" that we can safely call such
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* usage "undefined behaviour".
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*
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* For example, the constants AT_REMOVEDIR and AT_EACCESS have the same value.
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* AT_EACCESS is meaningful only to faccessat, while AT_REMOVEDIR is meaningful
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* only to unlinkat. The two functions do completely different things and
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* therefore, the flags can be allowed to overlap. For example, passing
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* AT_REMOVEDIR to faccessat would be undefined behavior and thus treating it
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* equivalent to AT_EACCESS is valid undefined behavior.
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*
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* Note for implementers: When picking a new per-syscall AT_* flag, try to
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* reuse already existing flags first. This leaves us with as many unused bits
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* as possible, so we can use them for generic bits in the future if necessary.
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*/
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#define AT_FDCWD -100 /* Special value used to indicate
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openat should use the current
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working directory. */
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#define AT_SYMLINK_NOFOLLOW 0x100 /* Do not follow symbolic links. */
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/* Flags for renameat2(2) (must match legacy RENAME_* flags). */
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#define AT_RENAME_NOREPLACE 0x0001
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#define AT_RENAME_EXCHANGE 0x0002
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#define AT_RENAME_WHITEOUT 0x0004
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/* Flag for faccessat(2). */
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#define AT_EACCESS 0x200 /* Test access permitted for
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effective IDs, not real IDs. */
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/* Flag for unlinkat(2). */
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#define AT_REMOVEDIR 0x200 /* Remove directory instead of
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unlinking file. */
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#define AT_SYMLINK_FOLLOW 0x400 /* Follow symbolic links. */
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#define AT_NO_AUTOMOUNT 0x800 /* Suppress terminal automount traversal */
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#define AT_EMPTY_PATH 0x1000 /* Allow empty relative pathname */
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#define AT_STATX_SYNC_TYPE 0x6000 /* Type of synchronisation required from statx() */
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#define AT_STATX_SYNC_AS_STAT 0x0000 /* - Do whatever stat() does */
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#define AT_STATX_FORCE_SYNC 0x2000 /* - Force the attributes to be sync'd with the server */
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#define AT_STATX_DONT_SYNC 0x4000 /* - Don't sync attributes with the server */
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#define AT_RECURSIVE 0x8000 /* Apply to the entire subtree */
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/* Flags for name_to_handle_at(2). */
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#define AT_HANDLE_FID 0x200 /* File handle is needed to compare
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object identity and may not be
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usable with open_by_handle_at(2). */
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#define AT_HANDLE_MNT_ID_UNIQUE 0x001 /* Return the u64 unique mount ID. */
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/* Flags for name_to_handle_at(2). We reuse AT_ flag space to save bits... */
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#define AT_HANDLE_FID AT_REMOVEDIR /* file handle is needed to
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compare object identity and may not
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be usable to open_by_handle_at(2) */
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#if defined(__KERNEL__)
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#define AT_GETATTR_NOSEC 0x80000000
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#endif

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