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From: Andrii Nakryiko <andrii@kernel.org>
To: linux-fsdevel@vger.kernel.org,
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	Andrii Nakryiko <andrii@kernel.org>
Subject: [PATCH v2 6/9] docs/procfs: call out ioctl()-based PROCMAP_QUERY command existence
Date: Thu, 23 May 2024 21:10:28 -0700
Message-ID: <20240524041032.1048094-7-andrii@kernel.org>
In-Reply-To: <20240524041032.1048094-1-andrii@kernel.org>
References: <20240524041032.1048094-1-andrii@kernel.org>
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Call out PROCMAP_QUERY ioctl() existence in the section describing
/proc/PID/maps file in documentation. We refer user to UAPI header for
low-level details of this programmatic interface.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
---
 Documentation/filesystems/proc.rst | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/Documentation/filesystems/proc.rst b/Documentation/filesystems/proc.rst
index 7c3a565ffbef..f2bbd1e86204 100644
--- a/Documentation/filesystems/proc.rst
+++ b/Documentation/filesystems/proc.rst
@@ -443,6 +443,14 @@ is not associated with a file:
 
  or if empty, the mapping is anonymous.
 
+Starting with 6.11 kernel, /proc/PID/maps provides an alternative
+ioctl()-based API that gives ability to flexibly and efficiently query and
+filter individual VMAs.  This interface is binary and is meant for more
+efficient programmatic use. `struct procmap_query`, defined in linux/fs.h UAPI
+header, serves as an input/output argument to the `PROCMAP_QUERY` ioctl()
+command. See comments in linus/fs.h UAPI header for details on query
+semantics, supported flags, data returned, and general API usage information.
+
 The /proc/PID/smaps is an extension based on maps, showing the memory
 consumption for each of the process's mappings. For each mapping (aka Virtual
 Memory Area, or VMA) there is a series of lines such as the following::
-- 
2.43.0