[PATCH v5] mm,hugetlb: remove mlock ulimit for SHM_HUGETLB

[zhangyiru <zhangyiru3@huawei.com>]

commit 21a3c273f88c9cbbaf7e ("mm, hugetlb: add thread name and pid to
SHM_HUGETLB mlock rlimit warning") marked this as deprecated in 2012,
but it is not deleted yet.

Mike says he still see that message in log files on occasion,
so maybe we should preserve this warning.

Signed-off-by: zhangyiru <zhangyiru3@huawei.com>
---
Changelog:
 v5: delete ucounts variable, and function calls that use ucounts in additon
 v4: modify context information of obsolete
 v3: modify warning message to obsolete
 v2: preserve warning message
 v1: remove mlock ulimit for SHM_HUGETLB
---
 fs/hugetlbfs/inode.c | 11 +++--------
 ipc/shm.c            |  3 +--
 mm/memfd.c           |  4 +---
 mm/mmap.c            |  3 +--
 4 files changed, 6 insertions(+), 15 deletions(-)

diff --git a/fs/hugetlbfs/inode.c b/fs/hugetlbfs/inode.c
index cdfb1ae78a3f..c7ef2ca16ba7 100644
--- a/fs/hugetlbfs/inode.c
+++ b/fs/hugetlbfs/inode.c
@@ -1446,8 +1446,8 @@ static int get_hstate_idx(int page_size_log)
  * otherwise hugetlb_reserve_pages reserves one less hugepages than intended.
  */
 struct file *hugetlb_file_setup(const char *name, size_t size,
-				vm_flags_t acctflag, struct ucounts **ucounts,
-				int creat_flags, int page_size_log)
+				vm_flags_t acctflag, int creat_flags,
+				int page_size_log)
 {
 	struct inode *inode;
 	struct vfsmount *mnt;
@@ -1458,7 +1458,6 @@ struct file *hugetlb_file_setup(const char *name, size_t size,
 	if (hstate_idx < 0)
 		return ERR_PTR(-ENODEV);
 
-	*ucounts = NULL;
 	mnt = hugetlbfs_vfsmount[hstate_idx];
 	if (!mnt)
 		return ERR_PTR(-ENOENT);
@@ -1466,14 +1465,10 @@ struct file *hugetlb_file_setup(const char *name, size_t size,
 	if (creat_flags == HUGETLB_SHMFS_INODE && !can_do_hugetlb_shm()) {
 		*ucounts = current_ucounts();
 		if (user_shm_lock(size, *ucounts)) {
-			task_lock(current);
 			pr_warn_once("%s (%d): Using mlock ulimits for SHM_HUGETLB is deprecated\n",
 				current->comm, current->pid);
-			task_unlock(current);
-		} else {
-			*ucounts = NULL;
+			user_shm_unlock(size, *ucounts);
 			return ERR_PTR(-EPERM);
-		}
 	}
 
 	file = ERR_PTR(-ENOSPC);
diff --git a/ipc/shm.c b/ipc/shm.c
index 748933e376ca..64f34aa074d1 100644
--- a/ipc/shm.c
+++ b/ipc/shm.c
@@ -650,8 +650,7 @@ static int newseg(struct ipc_namespace *ns, struct ipc_params *params)
 		if (shmflg & SHM_NORESERVE)
 			acctflag = VM_NORESERVE;
 		file = hugetlb_file_setup(name, hugesize, acctflag,
-				  &shp->mlock_ucounts, HUGETLB_SHMFS_INODE,
-				(shmflg >> SHM_HUGE_SHIFT) & SHM_HUGE_MASK);
+				, HUGETLB_SHMFS_INODE, (shmflg >> SHM_HUGE_SHIFT) & SHM_HUGE_MASK);
 	} else {
 		/*
 		 * Do not allow no accounting for OVERCOMMIT_NEVER, even
diff --git a/mm/memfd.c b/mm/memfd.c
index 081dd33e6a61..9f80f162791a 100644
--- a/mm/memfd.c
+++ b/mm/memfd.c
@@ -297,9 +297,7 @@ SYSCALL_DEFINE2(memfd_create,
 	}
 
 	if (flags & MFD_HUGETLB) {
-		struct ucounts *ucounts = NULL;
-
-		file = hugetlb_file_setup(name, 0, VM_NORESERVE, &ucounts,
+		file = hugetlb_file_setup(name, 0, VM_NORESERVE,
 					HUGETLB_ANONHUGE_INODE,
 					(flags >> MFD_HUGE_SHIFT) &
 					MFD_HUGE_MASK);
diff --git a/mm/mmap.c b/mm/mmap.c
index ca54d36d203a..da5b229e05b4 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -1608,7 +1608,6 @@ unsigned long ksys_mmap_pgoff(unsigned long addr, unsigned long len,
 			goto out_fput;
 		}
 	} else if (flags & MAP_HUGETLB) {
-		struct ucounts *ucounts = NULL;
 		struct hstate *hs;
 
 		hs = hstate_sizelog((flags >> MAP_HUGE_SHIFT) & MAP_HUGE_MASK);
@@ -1624,7 +1623,7 @@ unsigned long ksys_mmap_pgoff(unsigned long addr, unsigned long len,
 		 */
 		file = hugetlb_file_setup(HUGETLB_ANON_FILE, len,
 				VM_NORESERVE,
-				&ucounts, HUGETLB_ANONHUGE_INODE,
+				HUGETLB_ANONHUGE_INODE,
 				(flags >> MAP_HUGE_SHIFT) & MAP_HUGE_MASK);
 		if (IS_ERR(file))
 			return PTR_ERR(file);
-- 
2.27.0