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authorLinus Torvalds <torvalds@linux-foundation.org>2017-07-03 20:34:51 +0300
committerLinus Torvalds <torvalds@linux-foundation.org>2017-07-03 20:34:51 +0300
commitc6b1e36c8fa04a6680c44fe0321d0370400e90b6 (patch)
tree5110f0639bfa803baa8d213cb21efe37beeaf742 /lib
parent81e3e044897b0875a52953b3fb6241a33428e4f9 (diff)
parenta84ebb837b419787c2ece74efa566c998929cead (diff)
downloadlinux-c6b1e36c8fa04a6680c44fe0321d0370400e90b6.tar.xz
Merge branch 'for-4.13/block' of git://git.kernel.dk/linux-block
Pull core block/IO updates from Jens Axboe: "This is the main pull request for the block layer for 4.13. Not a huge round in terms of features, but there's a lot of churn related to some core cleanups. Note this depends on the UUID tree pull request, that Christoph already sent out. This pull request contains: - A series from Christoph, unifying the error/stats codes in the block layer. We now use blk_status_t everywhere, instead of using different schemes for different places. - Also from Christoph, some cleanups around request allocation and IO scheduler interactions in blk-mq. - And yet another series from Christoph, cleaning up how we handle and do bounce buffering in the block layer. - A blk-mq debugfs series from Bart, further improving on the support we have for exporting internal information to aid debugging IO hangs or stalls. - Also from Bart, a series that cleans up the request initialization differences across types of devices. - A series from Goldwyn Rodrigues, allowing the block layer to return failure if we will block and the user asked for non-blocking. - Patch from Hannes for supporting setting loop devices block size to that of the underlying device. - Two series of patches from Javier, fixing various issues with lightnvm, particular around pblk. - A series from me, adding support for write hints. This comes with NVMe support as well, so applications can help guide data placement on flash to improve performance, latencies, and write amplification. - A series from Ming, improving and hardening blk-mq support for stopping/starting and quiescing hardware queues. - Two pull requests for NVMe updates. Nothing major on the feature side, but lots of cleanups and bug fixes. From the usual crew. - A series from Neil Brown, greatly improving the bio rescue set support. Most notably, this kills the bio rescue work queues, if we don't really need them. - Lots of other little bug fixes that are all over the place" * 'for-4.13/block' of git://git.kernel.dk/linux-block: (217 commits) lightnvm: pblk: set line bitmap check under debug lightnvm: pblk: verify that cache read is still valid lightnvm: pblk: add initialization check lightnvm: pblk: remove target using async. I/Os lightnvm: pblk: use vmalloc for GC data buffer lightnvm: pblk: use right metadata buffer for recovery lightnvm: pblk: schedule if data is not ready lightnvm: pblk: remove unused return variable lightnvm: pblk: fix double-free on pblk init lightnvm: pblk: fix bad le64 assignations nvme: Makefile: remove dead build rule blk-mq: map all HWQ also in hyperthreaded system nvmet-rdma: register ib_client to not deadlock in device removal nvme_fc: fix error recovery on link down. nvmet_fc: fix crashes on bad opcodes nvme_fc: Fix crash when nvme controller connection fails. nvme_fc: replace ioabort msleep loop with completion nvme_fc: fix double calls to nvme_cleanup_cmd() nvme-fabrics: verify that a controller returns the correct NQN nvme: simplify nvme_dev_attrs_are_visible ...
Diffstat (limited to 'lib')
-rw-r--r--lib/scatterlist.c35
1 files changed, 35 insertions, 0 deletions
diff --git a/lib/scatterlist.c b/lib/scatterlist.c
index c6cf82242d65..be7b4dd6b68d 100644
--- a/lib/scatterlist.c
+++ b/lib/scatterlist.c
@@ -751,3 +751,38 @@ size_t sg_pcopy_to_buffer(struct scatterlist *sgl, unsigned int nents,
return sg_copy_buffer(sgl, nents, buf, buflen, skip, true);
}
EXPORT_SYMBOL(sg_pcopy_to_buffer);
+
+/**
+ * sg_zero_buffer - Zero-out a part of a SG list
+ * @sgl: The SG list
+ * @nents: Number of SG entries
+ * @buflen: The number of bytes to zero out
+ * @skip: Number of bytes to skip before zeroing
+ *
+ * Returns the number of bytes zeroed.
+ **/
+size_t sg_zero_buffer(struct scatterlist *sgl, unsigned int nents,
+ size_t buflen, off_t skip)
+{
+ unsigned int offset = 0;
+ struct sg_mapping_iter miter;
+ unsigned int sg_flags = SG_MITER_ATOMIC | SG_MITER_TO_SG;
+
+ sg_miter_start(&miter, sgl, nents, sg_flags);
+
+ if (!sg_miter_skip(&miter, skip))
+ return false;
+
+ while (offset < buflen && sg_miter_next(&miter)) {
+ unsigned int len;
+
+ len = min(miter.length, buflen - offset);
+ memset(miter.addr, 0, len);
+
+ offset += len;
+ }
+
+ sg_miter_stop(&miter);
+ return offset;
+}
+EXPORT_SYMBOL(sg_zero_buffer);