The patch titled
Subject: mm: use only pidfd for process_madvise syscall
has been added to the -mm tree. Its filename is
mm-use-only-pidfd-for-process_madvise-syscall.patch
This patch should soon appear at
http://ozlabs.org/~akpm/mmots/broken-out/mm-use-only-pidfd-for-process_madvise-syscall.patch
and later at
http://ozlabs.org/~akpm/mmotm/broken-out/mm-use-only-pidfd-for-process_madvise-syscall.patch
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*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***
The -mm tree is included into linux-next and is updated
there every 3-4 working days
------------------------------------------------------
From: Minchan Kim <minchan@xxxxxxxxxx>
Subject: mm: use only pidfd for process_madvise syscall
Based on discussion[1], people didn't feel we need to support both
pid and pidfd for every new coming API[2] so this patch keeps only
pidfd. This patch also changes flags's type with "unsigned int".
[1] https://lore.kernel.org/linux-mm/20200509124817.xmrvsrq3mla6b76k@wittgenstein/
[2] https://lore.kernel.org/linux-mm/9d849087-3359-c4ab-fbec-859e8186c509@xxxxxxxxxxxxx/
Link: http://lkml.kernel.org/r/20200518211350.GA50295@xxxxxxxxxx
Reviewed-by: Suren Baghdasaryan <surenb@xxxxxxxxxx>
Signed-off-by: Minchan Kim <minchan@xxxxxxxxxx>
Cc: David Rientjes <rientjes@xxxxxxxxxx>
Cc: Arjun Roy <arjunroy@xxxxxxxxxx>
Cc: Tim Murray <timmurray@xxxxxxxxxx>
Cc: Daniel Colascione <dancol@xxxxxxxxxx>
Cc: Sonny Rao <sonnyrao@xxxxxxxxxx>
Cc: Brian Geffon <bgeffon@xxxxxxxxxx>
Cc: Shakeel Butt <shakeelb@xxxxxxxxxx>
Cc: John Dias <joaodias@xxxxxxxxxx>
Cc: Joel Fernandes <joel@xxxxxxxxxxxxxxxxx>
Cc: SeongJae Park <sj38.park@xxxxxxxxx>
Cc: Oleksandr Natalenko <oleksandr@xxxxxxxxxx>
Cc: Sandeep Patil <sspatil@xxxxxxxxxx>
Cc: Michal Hocko <mhocko@xxxxxxxx>
Cc: Johannes Weiner <hannes@xxxxxxxxxxx>
Cc: Vlastimil Babka <vbabka@xxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/madvise.c | 42 +++++++++++++-----------------------------
1 file changed, 13 insertions(+), 29 deletions(-)
--- a/mm/madvise.c~mm-use-only-pidfd-for-process_madvise-syscall
+++ a/mm/madvise.c
@@ -1230,8 +1230,8 @@ static int process_madvise_vec(struct ta
return ret;
}
-static ssize_t do_process_madvise(int which, pid_t upid, struct iov_iter *iter,
- int behavior, unsigned long flags)
+static ssize_t do_process_madvise(int pidfd, struct iov_iter *iter,
+ int behavior, unsigned int flags)
{
ssize_t ret;
struct pid *pid;
@@ -1242,26 +1242,12 @@ static ssize_t do_process_madvise(int wh
if (flags != 0)
return -EINVAL;
- switch (which) {
- case P_PID:
- if (upid <= 0)
- return -EINVAL;
-
- pid = find_get_pid(upid);
- if (!pid)
- return -ESRCH;
- break;
- case P_PIDFD:
- if (upid < 0)
- return -EINVAL;
-
- pid = pidfd_get_pid(upid);
- if (IS_ERR(pid))
- return PTR_ERR(pid);
- break;
- default:
+ if (pidfd < 0)
return -EINVAL;
- }
+
+ pid = pidfd_get_pid(pidfd);
+ if (IS_ERR(pid))
+ return PTR_ERR(pid);
task = get_pid_task(pid, PIDTYPE_PID);
if (!task) {
@@ -1293,9 +1279,8 @@ put_pid:
return ret;
}
-SYSCALL_DEFINE6(process_madvise, int, which, pid_t, upid,
- const struct iovec __user *, vec, unsigned long, vlen,
- int, behavior, unsigned long, flags)
+SYSCALL_DEFINE5(process_madvise, int, pidfd, const struct iovec __user *, vec,
+ unsigned long, vlen, int, behavior, unsigned int, flags)
{
ssize_t ret;
struct iovec iovstack[UIO_FASTIOV];
@@ -1304,19 +1289,18 @@ SYSCALL_DEFINE6(process_madvise, int, wh
ret = import_iovec(READ, vec, vlen, ARRAY_SIZE(iovstack), &iov, &iter);
if (ret >= 0) {
- ret = do_process_madvise(which, upid, &iter, behavior, flags);
+ ret = do_process_madvise(pidfd, &iter, behavior, flags);
kfree(iov);
}
return ret;
}
#ifdef CONFIG_COMPAT
-COMPAT_SYSCALL_DEFINE6(process_madvise, compat_int_t, which,
- compat_pid_t, upid,
+COMPAT_SYSCALL_DEFINE5(process_madvise, compat_int_t, pidfd,
const struct compat_iovec __user *, vec,
compat_ulong_t, vlen,
compat_int_t, behavior,
- compat_ulong_t, flags)
+ compat_int_t, flags)
{
ssize_t ret;
@@ -1327,7 +1311,7 @@ COMPAT_SYSCALL_DEFINE6(process_madvise,
ret = compat_import_iovec(READ, vec, vlen, ARRAY_SIZE(iovstack),
&iov, &iter);
if (ret >= 0) {
- ret = do_process_madvise(which, upid, &iter, behavior, flags);
+ ret = do_process_madvise(pidfd, &iter, behavior, flags);
kfree(iov);
}
return ret;
_
Patches currently in -mm which might be from minchan@xxxxxxxxxx are
mm-pass-task-and-mm-to-do_madvise.patch
mm-introduce-external-memory-hinting-api.patch
mm-introduce-external-memory-hinting-api-fix.patch
mm-introduce-external-memory-hinting-api-fix-2.patch
mm-check-fatal-signal-pending-of-target-process.patch
pid-move-pidfd_get_pid-function-to-pidc.patch
mm-support-both-pid-and-pidfd-for-process_madvise.patch
mm-support-vector-address-ranges-for-process_madvise.patch
mm-support-vector-address-ranges-for-process_madvise-fix.patch
mm-support-vector-address-ranges-for-process_madvise-fix-fix-fix-fix.patch
mm-use-only-pidfd-for-process_madvise-syscall.patch
