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Fri, 04 Apr 2025 02:19:49 +0000 (GMT) Received: from pps.filterd (iadpaimrmta02.imrmtpd1.prodappiadaev1.oraclevcn.com [127.0.0.1]) by iadpaimrmta02.imrmtpd1.prodappiadaev1.oraclevcn.com (8.18.1.2/8.18.1.2) with ESMTP id 5340fRNl017354; Fri, 4 Apr 2025 02:19:48 GMT Received: from pps.reinject (localhost [127.0.0.1]) by iadpaimrmta02.imrmtpd1.prodappiadaev1.oraclevcn.com (PPS) with ESMTPS id 45t2pspjhj-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 04 Apr 2025 02:19:48 +0000 Received: from iadpaimrmta02.imrmtpd1.prodappiadaev1.oraclevcn.com (iadpaimrmta02.imrmtpd1.prodappiadaev1.oraclevcn.com [127.0.0.1]) by pps.reinject (8.17.1.5/8.17.1.5) with ESMTP id 5342H8hA030074; Fri, 4 Apr 2025 02:19:48 GMT Received: from localhost.localdomain (ca-dev60.us.oracle.com [10.129.136.27]) by iadpaimrmta02.imrmtpd1.prodappiadaev1.oraclevcn.com (PPS) with ESMTP id 45t2pspj73-18; Fri, 04 Apr 2025 02:19:47 +0000 From: Anthony Yznaga To: akpm@linux-foundation.org, willy@infradead.org, markhemm@googlemail.com, viro@zeniv.linux.org.uk, david@redhat.com, khalid@kernel.org Cc: anthony.yznaga@oracle.com, andreyknvl@gmail.com, dave.hansen@intel.com, luto@kernel.org, brauner@kernel.org, arnd@arndb.de, ebiederm@xmission.com, catalin.marinas@arm.com, linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, mhiramat@kernel.org, rostedt@goodmis.org, vasily.averin@linux.dev, xhao@linux.alibaba.com, pcc@google.com, neilb@suse.de, maz@kernel.org Subject: [PATCH v2 17/20] mm/mshare: Add an ioctl for unmapping objects in an mshare region Date: Thu, 3 Apr 2025 19:18:59 -0700 Message-ID: <20250404021902.48863-18-anthony.yznaga@oracle.com> X-Mailer: git-send-email 2.43.5 In-Reply-To: <20250404021902.48863-1-anthony.yznaga@oracle.com> References: <20250404021902.48863-1-anthony.yznaga@oracle.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1095,Hydra:6.0.680,FMLib:17.12.68.34 definitions=2025-04-04_01,2025-04-03_03,2024-11-22_01 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 phishscore=0 bulkscore=0 mlxscore=0 spamscore=0 adultscore=0 suspectscore=0 mlxlogscore=999 malwarescore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2502280000 definitions=main-2504040014 X-Proofpoint-ORIG-GUID: _v_EaYXFzgUP_UK3Jm0_mzqmEOIgUWb- X-Proofpoint-GUID: _v_EaYXFzgUP_UK3Jm0_mzqmEOIgUWb- Content-Type: text/plain; charset="utf-8" The arguments are the same as munmap() except that the start of the mapping is specified as an offset into the mshare region instead of as an address. Signed-off-by: Anthony Yznaga --- include/uapi/linux/msharefs.h | 7 ++++++ mm/mshare.c | 40 +++++++++++++++++++++++++++++++++++ 2 files changed, 47 insertions(+) diff --git a/include/uapi/linux/msharefs.h b/include/uapi/linux/msharefs.h index ad129beeef62..fb0235d1e384 100644 --- a/include/uapi/linux/msharefs.h +++ b/include/uapi/linux/msharefs.h @@ -19,6 +19,7 @@ * msharefs specific ioctl commands */ #define MSHAREFS_CREATE_MAPPING _IOW('x', 0, struct mshare_create) +#define MSHAREFS_UNMAP _IOW('x', 1, struct mshare_unmap) =20 struct mshare_create { __u64 region_offset; @@ -28,4 +29,10 @@ struct mshare_create { __u32 flags; __u32 fd; }; + +struct mshare_unmap { + __u64 region_offset; + __u64 size; +}; + #endif diff --git a/mm/mshare.c b/mm/mshare.c index be0aaa894963..a6106f6264cb 100644 --- a/mm/mshare.c +++ b/mm/mshare.c @@ -281,11 +281,41 @@ msharefs_create_mapping(struct mshare_data *m_data, s= truct mshare_create *mcreat return error; } =20 +static long +msharefs_unmap(struct mshare_data *m_data, struct mshare_unmap *munmap) +{ + struct mm_struct *host_mm =3D m_data->mm; + unsigned long mshare_start, mshare_end, mshare_size; + unsigned long region_offset =3D munmap->region_offset; + unsigned long size =3D munmap->size; + unsigned long addr; + int error; + + mshare_start =3D m_data->start; + mshare_size =3D m_data->size; + mshare_end =3D mshare_start + mshare_size; + addr =3D mshare_start + region_offset; + + if ((size > mshare_size) || (region_offset >=3D mshare_size) || + (addr + size > mshare_end)) + return -EINVAL; + + if (mmap_write_lock_killable(host_mm)) + return -EINTR; + + error =3D do_munmap(host_mm, addr, size, NULL); + + mmap_write_unlock(host_mm); + + return error; +} + static long msharefs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) { struct mshare_data *m_data =3D filp->private_data; struct mshare_create mcreate; + struct mshare_unmap munmap; =20 switch (cmd) { case MSHAREFS_CREATE_MAPPING: @@ -298,6 +328,16 @@ msharefs_ioctl(struct file *filp, unsigned int cmd, un= signed long arg) =20 return msharefs_create_mapping(m_data, &mcreate); =20 + case MSHAREFS_UNMAP: + if (copy_from_user(&munmap, (struct mshare_unmap __user *)arg, + sizeof(munmap))) + return -EFAULT; + + if (!test_bit(MSHARE_INITIALIZED, &m_data->flags)) + return -EINVAL; + + return msharefs_unmap(m_data, &munmap); + default: return -ENOTTY; } --=20 2.43.5