The patch titled
mlock: make mlock error return Posixly Correct
has been added to the -mm tree. Its filename is
mlock-make-mlock-error-return-posixly-correct.patch
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See http://www.zip.com.au/~akpm/linux/patches/stuff/added-to-mm.txt to find
out what to do about this
The current -mm tree may be found at http://userweb.kernel.org/~akpm/mmotm/
------------------------------------------------------
Subject: mlock: make mlock error return Posixly Correct
From: Lee Schermerhorn <lee.schermerhorn@xxxxxx>
Rework Posix error return for mlock().
Posix requires error code for mlock*() system calls for some conditions
that differ from what kernel low level functions, such as
get_user_pages(), return for those conditions. For more info, see:
http://marc.info/?l=linux-kernel&m=121750892930775&w=2
This patch provides the same translation of get_user_pages()
error codes to posix specified error codes in the context
of the mlock rework for unevictable lru.
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@xxxxxxxxxxxxxx>
Signed-off-by: Lee Schermerhorn <lee.schermerhorn@xxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/memory.c | 2 +-
mm/mlock.c | 27 +++++++++++++++++++++------
2 files changed, 22 insertions(+), 7 deletions(-)
diff -puN mm/memory.c~mlock-make-mlock-error-return-posixly-correct mm/memory.c
--- a/mm/memory.c~mlock-make-mlock-error-return-posixly-correct
+++ a/mm/memory.c
@@ -2821,7 +2821,7 @@ int make_pages_present(unsigned long add
len, write, 0, NULL, NULL);
if (ret < 0)
return ret;
- return ret == len ? 0 : -1;
+ return ret == len ? 0 : -EFAULT;
}
#if !defined(__HAVE_ARCH_GATE_AREA)
diff -puN mm/mlock.c~mlock-make-mlock-error-return-posixly-correct mm/mlock.c
--- a/mm/mlock.c~mlock-make-mlock-error-return-posixly-correct
+++ a/mm/mlock.c
@@ -143,6 +143,18 @@ static void munlock_vma_page(struct page
}
}
+/*
+ * convert get_user_pages() return value to posix mlock() error
+ */
+static int __mlock_posix_error_return(long retval)
+{
+ if (retval == -EFAULT)
+ retval = -ENOMEM;
+ else if (retval == -ENOMEM)
+ retval = -EAGAIN;
+ return retval;
+}
+
/**
* __mlock_vma_pages_range() - mlock/munlock a range of pages in the vma.
* @vma: target vma
@@ -248,11 +260,12 @@ static long __mlock_vma_pages_range(stru
addr += PAGE_SIZE; /* for next get_user_pages() */
nr_pages--;
}
+ ret = 0;
}
lru_add_drain_all(); /* to update stats */
- return 0; /* count entire vma as locked_vm */
+ return ret; /* count entire vma as locked_vm */
}
#else /* CONFIG_UNEVICTABLE_LRU */
@@ -265,7 +278,7 @@ static long __mlock_vma_pages_range(stru
int mlock)
{
if (mlock && (vma->vm_flags & VM_LOCKED))
- make_pages_present(start, end);
+ return make_pages_present(start, end);
return 0;
}
#endif /* CONFIG_UNEVICTABLE_LRU */
@@ -435,10 +448,7 @@ success:
downgrade_write(&mm->mmap_sem);
ret = __mlock_vma_pages_range(vma, start, end, 1);
- if (ret > 0) {
- mm->locked_vm -= ret;
- ret = 0;
- }
+
/*
* Need to reacquire mmap sem in write mode, as our callers
* expect this. We have no support for atomically upgrading
@@ -452,6 +462,11 @@ success:
/* non-NULL *prev must contain @start, but need to check @end */
if (!(*prev) || end > (*prev)->vm_end)
ret = -ENOMEM;
+ else if (ret > 0) {
+ mm->locked_vm -= ret;
+ ret = 0;
+ } else
+ ret = __mlock_posix_error_return(ret); /* translate if needed */
} else {
/*
* TODO: for unlocking, pages will already be resident, so
_
Patches currently in -mm which might be from lee.schermerhorn@xxxxxx are
vmscan-use-an-indexed-array-for-lru-variables.patch
define-page_file_cache-function.patch
vmscan-split-lru-lists-into-anon-file-sets.patch
pageflag-helpers-for-configed-out-flags.patch
unevictable-lru-infrastructure.patch
unevictable-lru-infrastructure-nommu-fix.patch
unevictable-lru-infrastructure-remember-pages-active-state.patch
unevictable-lru-infrastructure-defer-vm-event-counting.patch
unevictable-infrastructure-lru-add-event-counting-with-statistics.patch
unevictable-lru-page-statistics.patch
ramfs-and-ram-disk-pages-are-unevictable.patch
shm_locked-pages-are-unevictable.patch
shm_locked-pages-are-unevictable-add-event-counts-to-list-scan.patch
mlock-mlocked-pages-are-unevictable.patch
mlock-mlocked-pages-are-unevictable-fix.patch
doc-unevictable-lru-and-mlocked-pages-documentation.patch
doc-unevictable-lru-and-mlocked-pages-documentation-update.patch
doc-unevictable-lru-and-mlocked-pages-documentation-update-2.patch
mlock-downgrade-mmap-sem-while-populating-mlocked-regions.patch
mmap-handle-mlocked-pages-during-map-remap-unmap.patch
mmap-handle-mlocked-pages-during-map-remap-unmap-mlock-fix-__mlock_vma_pages_range-comment-block.patch
mmap-handle-mlocked-pages-during-map-remap-unmap-mlock-backout-locked_vm-adjustment-during-mmap.patch
mmap-handle-mlocked-pages-during-map-remap-unmap-mlock-resubmit-locked_vm-adjustment-as-separate-patch.patch
mmap-handle-mlocked-pages-during-map-remap-unmap-mlock-fix-return-value-for-munmap-mlock-vma-race.patch
mmap-handle-mlocked-pages-during-map-remap-unmap-mlock-update-locked_vm-on-munmap-of-mlocked-region.patch
vmstat-mlocked-pages-statistics.patch
vmstat-mlocked-pages-statistics-mlocked-pages-add-event-counting-with-statistics.patch
swap-cull-unevictable-pages-in-fault-path.patch
vmscan-unevictable-lru-scan-sysctl.patch
mlock-count-attempts-to-free-mlocked-page-2.patch
mlock-revert-mainline-handling-of-mlock-error-return.patch
mlock-make-mlock-error-return-posixly-correct.patch
--
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