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Diffstat (limited to 'drivers/md/dm-crypt.c')
-rw-r--r--drivers/md/dm-crypt.c17
1 files changed, 15 insertions, 2 deletions
diff --git a/drivers/md/dm-crypt.c b/drivers/md/dm-crypt.c
index 0f48fed44..0d28c5b9d 100644
--- a/drivers/md/dm-crypt.c
+++ b/drivers/md/dm-crypt.c
@@ -968,7 +968,8 @@ static void crypt_free_buffer_pages(struct crypt_config *cc, struct bio *clone);
/*
* Generate a new unfragmented bio with the given size
- * This should never violate the device limitations
+ * This should never violate the device limitations (but only because
+ * max_segment_size is being constrained to PAGE_SIZE).
*
* This function may be called concurrently. If we allocate from the mempool
* concurrently, there is a possibility of deadlock. For example, if we have
@@ -2058,9 +2059,20 @@ static int crypt_iterate_devices(struct dm_target *ti,
return fn(ti, cc->dev, cc->start, ti->len, data);
}
+static void crypt_io_hints(struct dm_target *ti, struct queue_limits *limits)
+{
+ /*
+ * Unfortunate constraint that is required to avoid the potential
+ * for exceeding underlying device's max_segments limits -- due to
+ * crypt_alloc_buffer() possibly allocating pages for the encryption
+ * bio that are not as physically contiguous as the original bio.
+ */
+ limits->max_segment_size = PAGE_SIZE;
+}
+
static struct target_type crypt_target = {
.name = "crypt",
- .version = {1, 14, 0},
+ .version = {1, 14, 1},
.module = THIS_MODULE,
.ctr = crypt_ctr,
.dtr = crypt_dtr,
@@ -2072,6 +2084,7 @@ static struct target_type crypt_target = {
.message = crypt_message,
.merge = crypt_merge,
.iterate_devices = crypt_iterate_devices,
+ .io_hints = crypt_io_hints,
};
static int __init dm_crypt_init(void)