The patch titled
Subject: mm: do not use helper functions for process_madvise
has been added to the -mm tree. Its filename is
mm-madvise-introduce-process_madvise-syscall-an-external-memory-hinting-api-fix-fix-fix-fix-fix-fix-fix.patch
This patch should soon appear at
https://ozlabs.org/~akpm/mmots/broken-out/mm-madvise-introduce-process_madvise-syscall-an-external-memory-hinting-api-fix-fix-fix-fix-fix-fix-fix.patch
and later at
https://ozlabs.org/~akpm/mmotm/broken-out/mm-madvise-introduce-process_madvise-syscall-an-external-memory-hinting-api-fix-fix-fix-fix-fix-fix-fix.patch
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The -mm tree is included into linux-next and is updated
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------------------------------------------------------
From: Minchan Kim <minchan@xxxxxxxxxx>
Subject: mm: do not use helper functions for process_madvise
This patch removes helper functions process_madvise_vec,
do_process_madvise and madv_import_iovec and use them inline.
Link: https://lkml.kernel.org/r/20200921175539.GB387368@xxxxxxxxxx
Signed-off-by: Minchan Kim <minchan@xxxxxxxxxx>
Cc: Christoph Hellwig <hch@xxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/madvise.c | 97 +++++++++++++++++++++----------------------------
1 file changed, 43 insertions(+), 54 deletions(-)
--- a/mm/madvise.c~mm-madvise-introduce-process_madvise-syscall-an-external-memory-hinting-api-fix-fix-fix-fix-fix-fix-fix
+++ a/mm/madvise.c
@@ -1166,37 +1166,40 @@ SYSCALL_DEFINE3(madvise, unsigned long,
return do_madvise(current->mm, start, len_in, behavior);
}
-static int process_madvise_vec(struct mm_struct *mm, struct iov_iter *iter, int behavior)
-{
- struct iovec iovec;
- int ret = 0;
-
- while (iov_iter_count(iter)) {
- iovec = iov_iter_iovec(iter);
- ret = do_madvise(mm, (unsigned long)iovec.iov_base, iovec.iov_len, behavior);
- if (ret < 0)
- break;
- iov_iter_advance(iter, iovec.iov_len);
- }
-
- return ret;
-}
-
-static ssize_t do_process_madvise(int pidfd, struct iov_iter *iter,
- int behavior, unsigned int flags)
+SYSCALL_DEFINE5(process_madvise, int, pidfd, const struct iovec __user *, vec,
+ size_t, vlen, int, behavior, unsigned int, flags)
{
ssize_t ret;
+ struct iovec iovstack[UIO_FASTIOV], iovec;
+ struct iovec *iov = iovstack;
+ struct iov_iter iter;
struct pid *pid;
struct task_struct *task;
struct mm_struct *mm;
- size_t total_len = iov_iter_count(iter);
+ size_t total_len;
+
+ if (flags != 0) {
+ ret = -EINVAL;
+ goto out;
+ }
- if (flags != 0)
- return -EINVAL;
+#ifdef CONFIG_COMPAT
+ if (in_compat_syscall())
+ ret = compat_import_iovec(READ,
+ (struct compat_iovec __user *)vec, vlen,
+ ARRAY_SIZE(iovstack), &iov, &iter);
+ else
+#endif
+ ret = import_iovec(READ, vec, vlen, ARRAY_SIZE(iovstack),
+ &iov, &iter);
+ if (ret < 0)
+ goto out;
pid = pidfd_get_pid(pidfd);
- if (IS_ERR(pid))
- return PTR_ERR(pid);
+ if (IS_ERR(pid)) {
+ ret = PTR_ERR(pid);
+ goto free_iov;
+ }
task = get_pid_task(pid, PIDTYPE_PID);
if (!task) {
@@ -1216,43 +1219,29 @@ static ssize_t do_process_madvise(int pi
goto release_task;
}
- ret = process_madvise_vec(mm, iter, behavior);
- if (ret >= 0)
- ret = total_len - iov_iter_count(iter);
+ total_len = iov_iter_count(&iter);
+
+ while (iov_iter_count(&iter)) {
+ iovec = iov_iter_iovec(&iter);
+ ret = do_madvise(mm, (unsigned long)iovec.iov_base,
+ iovec.iov_len, behavior);
+ if (ret < 0)
+ break;
+ iov_iter_advance(&iter, iovec.iov_len);
+ }
+
+ if (ret == 0)
+ ret = total_len - iov_iter_count(&iter);
mmput(mm);
+ return ret;
+
release_task:
put_task_struct(task);
put_pid:
put_pid(pid);
- return ret;
-}
-
-static inline int madv_import_iovec(int type, const struct iovec __user *uvec, size_t nr_segs,
- unsigned int fast_segs, struct iovec **iov, struct iov_iter *i)
-{
-#ifdef CONFIG_COMPAT
- if (in_compat_syscall())
- return compat_import_iovec(type, (struct compat_iovec __user *)uvec, nr_segs,
- fast_segs, iov, i);
-#endif
-
- return import_iovec(type, uvec, nr_segs, fast_segs, iov, i);
-}
-
-SYSCALL_DEFINE5(process_madvise, int, pidfd, const struct iovec __user *, vec,
- size_t, vlen, int, behavior, unsigned int, flags)
-{
- ssize_t ret;
- struct iovec iovstack[UIO_FASTIOV];
- struct iovec *iov = iovstack;
- struct iov_iter iter;
-
- ret = madv_import_iovec(READ, vec, vlen, ARRAY_SIZE(iovstack), &iov, &iter);
- if (ret < 0)
- return ret;
-
- ret = do_process_madvise(pidfd, &iter, behavior, flags);
+free_iov:
kfree(iov);
+out:
return ret;
}
_
Patches currently in -mm which might be from minchan@xxxxxxxxxx are
mm-validate-pmd-after-splitting.patch
mm-madvise-pass-mm-to-do_madvise.patch
pid-move-pidfd_get_pid-to-pidc.patch
mm-madvise-introduce-process_madvise-syscall-an-external-memory-hinting-api.patch
mm-madvise-introduce-process_madvise-syscall-an-external-memory-hinting-api-fix.patch
mm-madvise-introduce-process_madvise-syscall-an-external-memory-hinting-api-fix-fix-fix-fix-fix.patch
mm-madvise-introduce-process_madvise-syscall-an-external-memory-hinting-api-fix-fix-fix-fix-fix-fix-fix.patch
