The patch titled
Subject: selftest-add-mremap_dontunmap-selftest-fix
has been added to the -mm tree. Its filename is
selftest-add-mremap_dontunmap-selftest-fix.patch
This patch should soon appear at
http://ozlabs.org/~akpm/mmots/broken-out/selftest-add-mremap_dontunmap-selftest-fix.patch
and later at
http://ozlabs.org/~akpm/mmotm/broken-out/selftest-add-mremap_dontunmap-selftest-fix.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: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Subject: selftest-add-mremap_dontunmap-selftest-fix
convert eight-spaces to hard tabs
Cc: Brian Geffon <bgeffon@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
tools/testing/selftests/vm/mremap_dontunmap.c | 474 ++++++++--------
1 file changed, 237 insertions(+), 237 deletions(-)
--- a/tools/testing/selftests/vm/mremap_dontunmap.c~selftest-add-mremap_dontunmap-selftest-fix
+++ a/tools/testing/selftests/vm/mremap_dontunmap.c
@@ -25,10 +25,10 @@ char *page_buffer;
static void dump_maps(void)
{
- char cmd[32];
+ char cmd[32];
- snprintf(cmd, sizeof(cmd), "cat /proc/%d/maps", getpid());
- system(cmd);
+ snprintf(cmd, sizeof(cmd), "cat /proc/%d/maps", getpid());
+ system(cmd);
}
#define BUG_ON(condition, description) \
@@ -36,7 +36,7 @@ static void dump_maps(void)
if (condition) { \
fprintf(stderr, "[FAIL]\t%s():%d\t%s:%s\n", __func__, \
__LINE__, (description), strerror(errno)); \
- dump_maps(); \
+ dump_maps(); \
exit(1); \
} \
} while (0)
@@ -45,87 +45,87 @@ static void dump_maps(void)
// reporting tests as failed when it's run on an older kernel.
static int kernel_support_for_mremap_dontunmap()
{
- int ret = 0;
- unsigned long num_pages = 1;
- void *source_mapping = mmap(NULL, num_pages * page_size, PROT_NONE,
- MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
- BUG_ON(source_mapping == MAP_FAILED, "mmap");
-
- // This simple remap should only fail if MREMAP_DONTUNMAP isn't
- // supported.
- void *dest_mapping =
- mremap(source_mapping, num_pages * page_size, num_pages * page_size,
- MREMAP_DONTUNMAP | MREMAP_MAYMOVE, 0);
- if (dest_mapping == MAP_FAILED) {
- ret = errno;
- } else {
- BUG_ON(munmap(dest_mapping, num_pages * page_size) == -1,
- "unable to unmap destination mapping");
- }
-
- BUG_ON(munmap(source_mapping, num_pages * page_size) == -1,
- "unable to unmap source mapping");
- return ret;
+ int ret = 0;
+ unsigned long num_pages = 1;
+ void *source_mapping = mmap(NULL, num_pages * page_size, PROT_NONE,
+ MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
+ BUG_ON(source_mapping == MAP_FAILED, "mmap");
+
+ // This simple remap should only fail if MREMAP_DONTUNMAP isn't
+ // supported.
+ void *dest_mapping =
+ mremap(source_mapping, num_pages * page_size, num_pages * page_size,
+ MREMAP_DONTUNMAP | MREMAP_MAYMOVE, 0);
+ if (dest_mapping == MAP_FAILED) {
+ ret = errno;
+ } else {
+ BUG_ON(munmap(dest_mapping, num_pages * page_size) == -1,
+ "unable to unmap destination mapping");
+ }
+
+ BUG_ON(munmap(source_mapping, num_pages * page_size) == -1,
+ "unable to unmap source mapping");
+ return ret;
}
// This helper will just validate that an entire mapping contains the expected
// byte.
static int check_region_contains_byte(void *addr, unsigned long size, char byte)
{
- BUG_ON(size & (page_size - 1),
- "check_region_contains_byte expects page multiples");
- BUG_ON((unsigned long)addr & (page_size - 1),
- "check_region_contains_byte expects page alignment");
-
- memset(page_buffer, byte, page_size);
-
- unsigned long num_pages = size / page_size;
- unsigned long i;
-
- // Compare each page checking that it contains our expected byte.
- for (i = 0; i < num_pages; ++i) {
- int ret =
- memcmp(addr + (i * page_size), page_buffer, page_size);
- if (ret) {
- return ret;
- }
- }
+ BUG_ON(size & (page_size - 1),
+ "check_region_contains_byte expects page multiples");
+ BUG_ON((unsigned long)addr & (page_size - 1),
+ "check_region_contains_byte expects page alignment");
+
+ memset(page_buffer, byte, page_size);
+
+ unsigned long num_pages = size / page_size;
+ unsigned long i;
+
+ // Compare each page checking that it contains our expected byte.
+ for (i = 0; i < num_pages; ++i) {
+ int ret =
+ memcmp(addr + (i * page_size), page_buffer, page_size);
+ if (ret) {
+ return ret;
+ }
+ }
- return 0;
+ return 0;
}
// this test validates that MREMAP_DONTUNMAP moves the pagetables while leaving
// the source mapping mapped.
static void mremap_dontunmap_simple()
{
- unsigned long num_pages = 5;
+ unsigned long num_pages = 5;
- void *source_mapping =
- mmap(NULL, num_pages * page_size, PROT_READ | PROT_WRITE,
- MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
- BUG_ON(source_mapping == MAP_FAILED, "mmap");
-
- memset(source_mapping, 'a', num_pages * page_size);
-
- // Try to just move the whole mapping anywhere (not fixed).
- void *dest_mapping =
- mremap(source_mapping, num_pages * page_size, num_pages * page_size,
- MREMAP_DONTUNMAP | MREMAP_MAYMOVE, NULL);
- BUG_ON(dest_mapping == MAP_FAILED, "mremap");
-
- // Validate that the pages have been moved, we know they were moved if
- // the dest_mapping contains a's.
- BUG_ON(check_region_contains_byte
- (dest_mapping, num_pages * page_size, 'a') != 0,
- "pages did not migrate");
- BUG_ON(check_region_contains_byte
- (source_mapping, num_pages * page_size, 0) != 0,
- "source should have no ptes");
-
- BUG_ON(munmap(dest_mapping, num_pages * page_size) == -1,
- "unable to unmap destination mapping");
- BUG_ON(munmap(source_mapping, num_pages * page_size) == -1,
- "unable to unmap source mapping");
+ void *source_mapping =
+ mmap(NULL, num_pages * page_size, PROT_READ | PROT_WRITE,
+ MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
+ BUG_ON(source_mapping == MAP_FAILED, "mmap");
+
+ memset(source_mapping, 'a', num_pages * page_size);
+
+ // Try to just move the whole mapping anywhere (not fixed).
+ void *dest_mapping =
+ mremap(source_mapping, num_pages * page_size, num_pages * page_size,
+ MREMAP_DONTUNMAP | MREMAP_MAYMOVE, NULL);
+ BUG_ON(dest_mapping == MAP_FAILED, "mremap");
+
+ // Validate that the pages have been moved, we know they were moved if
+ // the dest_mapping contains a's.
+ BUG_ON(check_region_contains_byte
+ (dest_mapping, num_pages * page_size, 'a') != 0,
+ "pages did not migrate");
+ BUG_ON(check_region_contains_byte
+ (source_mapping, num_pages * page_size, 0) != 0,
+ "source should have no ptes");
+
+ BUG_ON(munmap(dest_mapping, num_pages * page_size) == -1,
+ "unable to unmap destination mapping");
+ BUG_ON(munmap(source_mapping, num_pages * page_size) == -1,
+ "unable to unmap source mapping");
}
// This test validates MREMAP_DONTUNMAP will move page tables to a specific
@@ -133,194 +133,194 @@ static void mremap_dontunmap_simple()
// remains intact.
static void mremap_dontunmap_simple_fixed()
{
- unsigned long num_pages = 5;
+ unsigned long num_pages = 5;
- // Since we want to guarantee that we can remap to a point, we will
- // create a mapping up front.
- void *dest_mapping =
- mmap(NULL, num_pages * page_size, PROT_READ | PROT_WRITE,
- MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
- BUG_ON(dest_mapping == MAP_FAILED, "mmap");
- memset(dest_mapping, 'X', num_pages * page_size);
-
- void *source_mapping =
- mmap(NULL, num_pages * page_size, PROT_READ | PROT_WRITE,
- MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
- BUG_ON(source_mapping == MAP_FAILED, "mmap");
- memset(source_mapping, 'a', num_pages * page_size);
-
- void *remapped_mapping =
- mremap(source_mapping, num_pages * page_size, num_pages * page_size,
- MREMAP_FIXED | MREMAP_DONTUNMAP | MREMAP_MAYMOVE,
- dest_mapping);
- BUG_ON(remapped_mapping == MAP_FAILED, "mremap");
- BUG_ON(remapped_mapping != dest_mapping,
- "mremap should have placed the remapped mapping at dest_mapping");
-
- // The dest mapping will have been unmap by mremap so we expect the Xs
- // to be gone and replaced with a's.
- BUG_ON(check_region_contains_byte
- (dest_mapping, num_pages * page_size, 'a') != 0,
- "pages did not migrate");
-
- // And the source mapping will have had its ptes dropped.
- BUG_ON(check_region_contains_byte
- (source_mapping, num_pages * page_size, 0) != 0,
- "source should have no ptes");
-
- BUG_ON(munmap(dest_mapping, num_pages * page_size) == -1,
- "unable to unmap destination mapping");
- BUG_ON(munmap(source_mapping, num_pages * page_size) == -1,
- "unable to unmap source mapping");
+ // Since we want to guarantee that we can remap to a point, we will
+ // create a mapping up front.
+ void *dest_mapping =
+ mmap(NULL, num_pages * page_size, PROT_READ | PROT_WRITE,
+ MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
+ BUG_ON(dest_mapping == MAP_FAILED, "mmap");
+ memset(dest_mapping, 'X', num_pages * page_size);
+
+ void *source_mapping =
+ mmap(NULL, num_pages * page_size, PROT_READ | PROT_WRITE,
+ MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
+ BUG_ON(source_mapping == MAP_FAILED, "mmap");
+ memset(source_mapping, 'a', num_pages * page_size);
+
+ void *remapped_mapping =
+ mremap(source_mapping, num_pages * page_size, num_pages * page_size,
+ MREMAP_FIXED | MREMAP_DONTUNMAP | MREMAP_MAYMOVE,
+ dest_mapping);
+ BUG_ON(remapped_mapping == MAP_FAILED, "mremap");
+ BUG_ON(remapped_mapping != dest_mapping,
+ "mremap should have placed the remapped mapping at dest_mapping");
+
+ // The dest mapping will have been unmap by mremap so we expect the Xs
+ // to be gone and replaced with a's.
+ BUG_ON(check_region_contains_byte
+ (dest_mapping, num_pages * page_size, 'a') != 0,
+ "pages did not migrate");
+
+ // And the source mapping will have had its ptes dropped.
+ BUG_ON(check_region_contains_byte
+ (source_mapping, num_pages * page_size, 0) != 0,
+ "source should have no ptes");
+
+ BUG_ON(munmap(dest_mapping, num_pages * page_size) == -1,
+ "unable to unmap destination mapping");
+ BUG_ON(munmap(source_mapping, num_pages * page_size) == -1,
+ "unable to unmap source mapping");
}
// This test validates that we can MREMAP_DONTUNMAP for a portion of an
// existing mapping.
static void mremap_dontunmap_partial_mapping()
{
- /*
- * source mapping:
- * --------------
- * | aaaaaaaaaa |
- * --------------
- * to become:
- * --------------
- * | aaaaa00000 |
- * --------------
- * With the destination mapping containing 5 pages of As.
- * ---------
- * | aaaaa |
- * ---------
- */
- unsigned long num_pages = 10;
- void *source_mapping =
- mmap(NULL, num_pages * page_size, PROT_READ | PROT_WRITE,
- MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
- BUG_ON(source_mapping == MAP_FAILED, "mmap");
- memset(source_mapping, 'a', num_pages * page_size);
-
- // We will grab the last 5 pages of the source and move them.
- void *dest_mapping =
- mremap(source_mapping + (5 * page_size), 5 * page_size,
- 5 * page_size,
- MREMAP_DONTUNMAP | MREMAP_MAYMOVE, NULL);
- BUG_ON(dest_mapping == MAP_FAILED, "mremap");
-
- // We expect the first 5 pages of the source to contain a's and the
- // final 5 pages to contain zeros.
- BUG_ON(check_region_contains_byte(source_mapping, 5 * page_size, 'a') !=
- 0, "first 5 pages of source should have original pages");
- BUG_ON(check_region_contains_byte
- (source_mapping + (5 * page_size), 5 * page_size, 0) != 0,
- "final 5 pages of source should have no ptes");
-
- // Finally we expect the destination to have 5 pages worth of a's.
- BUG_ON(check_region_contains_byte(dest_mapping, 5 * page_size, 'a') !=
- 0, "dest mapping should contain ptes from the source");
-
- BUG_ON(munmap(dest_mapping, 5 * page_size) == -1,
- "unable to unmap destination mapping");
- BUG_ON(munmap(source_mapping, num_pages * page_size) == -1,
- "unable to unmap source mapping");
+ /*
+ * source mapping:
+ * --------------
+ * | aaaaaaaaaa |
+ * --------------
+ * to become:
+ * --------------
+ * | aaaaa00000 |
+ * --------------
+ * With the destination mapping containing 5 pages of As.
+ * ---------
+ * | aaaaa |
+ * ---------
+ */
+ unsigned long num_pages = 10;
+ void *source_mapping =
+ mmap(NULL, num_pages * page_size, PROT_READ | PROT_WRITE,
+ MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
+ BUG_ON(source_mapping == MAP_FAILED, "mmap");
+ memset(source_mapping, 'a', num_pages * page_size);
+
+ // We will grab the last 5 pages of the source and move them.
+ void *dest_mapping =
+ mremap(source_mapping + (5 * page_size), 5 * page_size,
+ 5 * page_size,
+ MREMAP_DONTUNMAP | MREMAP_MAYMOVE, NULL);
+ BUG_ON(dest_mapping == MAP_FAILED, "mremap");
+
+ // We expect the first 5 pages of the source to contain a's and the
+ // final 5 pages to contain zeros.
+ BUG_ON(check_region_contains_byte(source_mapping, 5 * page_size, 'a') !=
+ 0, "first 5 pages of source should have original pages");
+ BUG_ON(check_region_contains_byte
+ (source_mapping + (5 * page_size), 5 * page_size, 0) != 0,
+ "final 5 pages of source should have no ptes");
+
+ // Finally we expect the destination to have 5 pages worth of a's.
+ BUG_ON(check_region_contains_byte(dest_mapping, 5 * page_size, 'a') !=
+ 0, "dest mapping should contain ptes from the source");
+
+ BUG_ON(munmap(dest_mapping, 5 * page_size) == -1,
+ "unable to unmap destination mapping");
+ BUG_ON(munmap(source_mapping, num_pages * page_size) == -1,
+ "unable to unmap source mapping");
}
// This test validates that we can shrink an existing mapping via the normal
// mremap behavior along with the MREMAP_DONTUNMAP flag.
static void mremap_dontunmap_shrink_mapping()
{
- /*
- * We shrink the source by 5 pages while remapping.
- * source mapping:
- * --------------
- * | aaaaaaaaaa |
- * --------------
- * to become:
- * ---------
- * | 00000 |
- * ---------
- * With the destination mapping containing 5 pages of As followed by
- * the original pages of Xs.
- * --------------
- * | aaaaaXXXXX |
- * --------------
- */
-
- unsigned long num_pages = 10;
-
- // We use MREMAP_FIXED because we don't want the mremap to place the
- // remapped mapping behind the source, if it did
- // we wouldn't be able to validate that the mapping was in fact
- // adjusted.
- void *dest_mapping =
- mmap(NULL, num_pages * page_size, PROT_READ | PROT_WRITE,
- MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
- BUG_ON(dest_mapping == MAP_FAILED, "mmap");
- memset(dest_mapping, 'X', num_pages * page_size);
-
- void *source_mapping =
- mmap(NULL, num_pages * page_size, PROT_READ | PROT_WRITE,
- MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
- BUG_ON(source_mapping == MAP_FAILED, "mmap");
- memset(source_mapping, 'a', num_pages * page_size);
-
- // We are shrinking the mapping while also using MREMAP_DONTUNMAP
- void *remapped_mapping =
- mremap(source_mapping, num_pages * page_size, 5 * page_size,
- MREMAP_FIXED | MREMAP_DONTUNMAP | MREMAP_MAYMOVE,
- dest_mapping);
- BUG_ON(remapped_mapping == MAP_FAILED, "mremap");
- BUG_ON(remapped_mapping != dest_mapping,
- "expected mremap to place mapping at dest");
-
- // The last 5 pages of source should have become unmapped while the
- // first 5 remain.
- unsigned char buf[5];
- int ret = mincore(source_mapping + (5 * page_size), 5 * page_size, buf);
- BUG_ON((ret != -1 || (ret == -1 && errno != ENOMEM)),
- "we expect -ENOMEM from mincore.");
-
- BUG_ON(check_region_contains_byte(source_mapping, 5 * page_size, 0) !=
- 0, "source should have no ptes");
- BUG_ON(check_region_contains_byte(dest_mapping, 5 * page_size, 'a') !=
- 0, "dest mapping should contain ptes from the source");
-
- // And the second half of the destination should be unchanged.
- BUG_ON(check_region_contains_byte(dest_mapping + (5 * page_size),
- 5 * page_size, 'X') != 0,
- "second half of dest shouldn't be touched");
-
- // Cleanup
- BUG_ON(munmap(dest_mapping, num_pages * page_size) == -1,
- "unable to unmap destination mapping");
- BUG_ON(munmap(source_mapping, 5 * page_size) == -1,
- "unable to unmap source mapping");
+ /*
+ * We shrink the source by 5 pages while remapping.
+ * source mapping:
+ * --------------
+ * | aaaaaaaaaa |
+ * --------------
+ * to become:
+ * ---------
+ * | 00000 |
+ * ---------
+ * With the destination mapping containing 5 pages of As followed by
+ * the original pages of Xs.
+ * --------------
+ * | aaaaaXXXXX |
+ * --------------
+ */
+
+ unsigned long num_pages = 10;
+
+ // We use MREMAP_FIXED because we don't want the mremap to place the
+ // remapped mapping behind the source, if it did
+ // we wouldn't be able to validate that the mapping was in fact
+ // adjusted.
+ void *dest_mapping =
+ mmap(NULL, num_pages * page_size, PROT_READ | PROT_WRITE,
+ MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
+ BUG_ON(dest_mapping == MAP_FAILED, "mmap");
+ memset(dest_mapping, 'X', num_pages * page_size);
+
+ void *source_mapping =
+ mmap(NULL, num_pages * page_size, PROT_READ | PROT_WRITE,
+ MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
+ BUG_ON(source_mapping == MAP_FAILED, "mmap");
+ memset(source_mapping, 'a', num_pages * page_size);
+
+ // We are shrinking the mapping while also using MREMAP_DONTUNMAP
+ void *remapped_mapping =
+ mremap(source_mapping, num_pages * page_size, 5 * page_size,
+ MREMAP_FIXED | MREMAP_DONTUNMAP | MREMAP_MAYMOVE,
+ dest_mapping);
+ BUG_ON(remapped_mapping == MAP_FAILED, "mremap");
+ BUG_ON(remapped_mapping != dest_mapping,
+ "expected mremap to place mapping at dest");
+
+ // The last 5 pages of source should have become unmapped while the
+ // first 5 remain.
+ unsigned char buf[5];
+ int ret = mincore(source_mapping + (5 * page_size), 5 * page_size, buf);
+ BUG_ON((ret != -1 || (ret == -1 && errno != ENOMEM)),
+ "we expect -ENOMEM from mincore.");
+
+ BUG_ON(check_region_contains_byte(source_mapping, 5 * page_size, 0) !=
+ 0, "source should have no ptes");
+ BUG_ON(check_region_contains_byte(dest_mapping, 5 * page_size, 'a') !=
+ 0, "dest mapping should contain ptes from the source");
+
+ // And the second half of the destination should be unchanged.
+ BUG_ON(check_region_contains_byte(dest_mapping + (5 * page_size),
+ 5 * page_size, 'X') != 0,
+ "second half of dest shouldn't be touched");
+
+ // Cleanup
+ BUG_ON(munmap(dest_mapping, num_pages * page_size) == -1,
+ "unable to unmap destination mapping");
+ BUG_ON(munmap(source_mapping, 5 * page_size) == -1,
+ "unable to unmap source mapping");
}
int main(void)
{
- page_size = sysconf(_SC_PAGE_SIZE);
+ page_size = sysconf(_SC_PAGE_SIZE);
- // test for kernel support for MREMAP_DONTUNMAP skipping the test if
- // not.
- if (kernel_support_for_mremap_dontunmap() != 0) {
+ // test for kernel support for MREMAP_DONTUNMAP skipping the test if
+ // not.
+ if (kernel_support_for_mremap_dontunmap() != 0) {
printf("No kernel support for MREMAP_DONTUNMAP\n");
return KSFT_SKIP;
}
- // Keep a page sized buffer around for when we need it.
- page_buffer =
- mmap(NULL, page_size, PROT_READ | PROT_WRITE,
- MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
- BUG_ON(page_buffer == MAP_FAILED, "unable to mmap a page.");
-
- mremap_dontunmap_simple();
- mremap_dontunmap_simple_fixed();
- mremap_dontunmap_partial_mapping();
- mremap_dontunmap_shrink_mapping();
+ // Keep a page sized buffer around for when we need it.
+ page_buffer =
+ mmap(NULL, page_size, PROT_READ | PROT_WRITE,
+ MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
+ BUG_ON(page_buffer == MAP_FAILED, "unable to mmap a page.");
+
+ mremap_dontunmap_simple();
+ mremap_dontunmap_simple_fixed();
+ mremap_dontunmap_partial_mapping();
+ mremap_dontunmap_shrink_mapping();
- BUG_ON(munmap(page_buffer, page_size) == -1,
- "unable to unmap page buffer");
+ BUG_ON(munmap(page_buffer, page_size) == -1,
+ "unable to unmap page buffer");
- printf("OK\n");
- return 0;
+ printf("OK\n");
+ return 0;
}
_
Patches currently in -mm which might be from akpm@xxxxxxxxxxxxxxxxxxxx are
mm.patch
mm-add-vm_insert_pages-fix.patch
net-zerocopy-use-vm_insert_pages-for-tcp-rcv-zerocopy-fix.patch
selftest-add-mremap_dontunmap-selftest-fix.patch
hugetlb_cgroup-add-reservation-accounting-for-private-mappings-fix.patch
hugetlb_cgroup-add-accounting-for-shared-mappings-fix.patch
mm-migratec-migrate-pg_readahead-flag-fix.patch
linux-next-rejects.patch
linux-next-git-rejects.patch
linux-next-fix.patch
drivers-tty-serial-sh-scic-suppress-warning.patch
kernel-forkc-export-kernel_thread-to-modules.patch
