[RFC PATCH 10/15] drivers/dax: Expand lock scope to cover the use of addresses
From: <hidden>
Date: 2020-07-14 07:05:22
Also in:
linux-fsdevel, linux-kselftest, linux-mm, lkml, nvdimm
Subsystem:
device direct access (dax), the rest · Maintainers:
Dan Williams, Vishal Verma, Dave Jiang, Alison Schofield, Linus Torvalds
From: Ira Weiny <redacted> The addition of PKS protection to dax read lock/unlock will require that the address returned by dax_direct_access() be protected by this lock. While not technically necessary for this series, this corrects the locking by ensuring that the use of kaddr and end_kaddr are covered by the dax read lock/unlock. Change the lock scope to cover the kaddr and end_kaddr use. Reviewed-by: Dan Williams <redacted> Signed-off-by: Ira Weiny <redacted> --- drivers/dax/super.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/dax/super.c b/drivers/dax/super.c
index 8e32345be0f7..021739768093 100644
--- a/drivers/dax/super.c
+++ b/drivers/dax/super.c@@ -103,11 +103,11 @@ bool __generic_fsdax_supported(struct dax_device *dax_dev, id = dax_read_lock(); len = dax_direct_access(dax_dev, pgoff, 1, &kaddr, &pfn); len2 = dax_direct_access(dax_dev, pgoff_end, 1, &end_kaddr, &end_pfn); - dax_read_unlock(id); if (len < 1 || len2 < 1) { pr_debug("%s: error: dax access failed (%ld)\n", bdevname(bdev, buf), len < 1 ? len : len2); + dax_read_unlock(id); return false; }
@@ -137,6 +137,7 @@ bool __generic_fsdax_supported(struct dax_device *dax_dev, put_dev_pagemap(end_pgmap); } + dax_read_unlock(id); if (!dax_enabled) { pr_debug("%s: error: dax support not enabled\n",
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2.25.1