xen/blkback: Fixed up comments and converted spaces to tabs.
Suggested-by: Ian Campbell <Ian.Campbell@eu.citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
This commit is contained in:
Konrad Rzeszutek Wilk
Родитель
3d68b39926
Коммит
01f37f2d53
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@ -73,13 +73,13 @@ module_param(debug_lvl, int, 0644);
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* response queued for it, with the saved 'id' passed back.
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*/
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struct pending_req {
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struct blkif_st *blkif;
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u64 id;
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int nr_pages;
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atomic_t pendcnt;
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unsigned short operation;
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int status;
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struct list_head free_list;
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struct blkif_st *blkif;
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u64 id;
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int nr_pages;
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atomic_t pendcnt;
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unsigned short operation;
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int status;
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struct list_head free_list;
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};
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#define BLKBACK_INVALID_HANDLE (~0)
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@ -103,7 +103,8 @@ static struct xen_blkbk *blkbk;
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* Little helpful macro to figure out the index and virtual address of the
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* pending_pages[..]. For each 'pending_req' we have have up to
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* BLKIF_MAX_SEGMENTS_PER_REQUEST (11) pages. The seg would be from 0 through
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* 10 and would index in the pending_pages[..]. */
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* 10 and would index in the pending_pages[..].
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*/
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static inline int vaddr_pagenr(struct pending_req *req, int seg)
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{
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return (req - blkbk->pending_reqs) *
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@ -167,8 +168,6 @@ static void free_req(struct pending_req *req)
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/*
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* Routines for managing virtual block devices (vbds).
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*/
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static int vbd_translate(struct phys_req *req, struct blkif_st *blkif,
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int operation)
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{
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@ -315,7 +314,7 @@ struct seg_buf {
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/*
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* Unmap the grant references, and also remove the M2P over-rides
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* used in the 'pending_req'.
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*/
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*/
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static void xen_blkbk_unmap(struct pending_req *req)
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{
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struct gnttab_unmap_grant_ref unmap[BLKIF_MAX_SEGMENTS_PER_REQUEST];
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@ -336,27 +335,32 @@ static void xen_blkbk_unmap(struct pending_req *req)
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ret = HYPERVISOR_grant_table_op(
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GNTTABOP_unmap_grant_ref, unmap, invcount);
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BUG_ON(ret);
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/* Note, we use invcount, so nr->pages, so we can't index
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/*
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* Note, we use invcount, so nr->pages, so we can't index
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* using vaddr(req, i).
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*/
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for (i = 0; i < invcount; i++) {
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ret = m2p_remove_override(
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virt_to_page(unmap[i].host_addr), false);
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if (ret) {
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printk(KERN_ALERT "Failed to remove M2P override for " \
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"%lx\n", (unsigned long)unmap[i].host_addr);
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printk(KERN_ALERT "Failed to remove M2P override for %lx\n",
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(unsigned long)unmap[i].host_addr);
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continue;
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}
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}
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}
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static int xen_blkbk_map(struct blkif_request *req, struct pending_req *pending_req,
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static int xen_blkbk_map(struct blkif_request *req,
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struct pending_req *pending_req,
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struct seg_buf seg[])
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{
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struct gnttab_map_grant_ref map[BLKIF_MAX_SEGMENTS_PER_REQUEST];
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int i;
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int nseg = req->nr_segments;
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int ret = 0;
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/* Fill out preq.nr_sects with proper amount of sectors, and setup
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/*
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* Fill out preq.nr_sects with proper amount of sectors, and setup
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* assign map[..] with the PFN of the page in our domain with the
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* corresponding grant reference for each page.
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*/
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@ -367,13 +371,15 @@ static int xen_blkbk_map(struct blkif_request *req, struct pending_req *pending_
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if (pending_req->operation != BLKIF_OP_READ)
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flags |= GNTMAP_readonly;
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gnttab_set_map_op(&map[i], vaddr(pending_req, i), flags,
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req->u.rw.seg[i].gref, pending_req->blkif->domid);
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req->u.rw.seg[i].gref,
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pending_req->blkif->domid);
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}
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ret = HYPERVISOR_grant_table_op(GNTTABOP_map_grant_ref, map, nseg);
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BUG_ON(ret);
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/* Now swizzel the MFN in our domain with the MFN from the other domain
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/*
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* Now swizzle the MFN in our domain with the MFN from the other domain
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* so that when we access vaddr(pending_req,i) it has the contents of
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* the page from the other domain.
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*/
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@ -423,7 +429,8 @@ static void __end_block_io_op(struct pending_req *pending_req, int error)
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pending_req->status = BLKIF_RSP_ERROR;
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}
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/* If all of the bio's have completed it is time to unmap
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/*
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* If all of the bio's have completed it is time to unmap
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* the grant references associated with 'request' and provide
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* the proper response on the ring.
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*/
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@ -510,8 +517,8 @@ static int do_block_io_op(struct blkif_st *blkif)
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}
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/*
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* Transumation of the 'struct blkif_request' to a proper 'struct bio'
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* and call the 'submit_bio' to pass it to the underlaying storage.
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* Transmutation of the 'struct blkif_request' to a proper 'struct bio'
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* and call the 'submit_bio' to pass it to the underlying storage.
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*/
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static int dispatch_rw_block_io(struct blkif_st *blkif,
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struct blkif_request *req,
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@ -538,8 +545,10 @@ static int dispatch_rw_block_io(struct blkif_st *blkif,
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case BLKIF_OP_FLUSH_DISKCACHE:
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blkif->st_f_req++;
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operation = WRITE_FLUSH;
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/* The frontend likes to set this to -1, which vbd_translate
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* is alergic too. */
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/*
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* The frontend likes to set this to -1, which vbd_translate
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* is alergic too.
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*/
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req->u.rw.sector_number = 0;
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break;
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case BLKIF_OP_WRITE_BARRIER:
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@ -585,8 +594,11 @@ static int dispatch_rw_block_io(struct blkif_st *blkif,
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preq.sector_number + preq.nr_sects, preq.dev);
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goto fail_response;
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}
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/* This check _MUST_ be done after vbd_translate as the preq.bdev
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* is set there. */
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/*
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* This check _MUST_ be done after vbd_translate as the preq.bdev
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* is set there.
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*/
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for (i = 0; i < nseg; i++) {
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if (((int)preq.sector_number|(int)seg[i].nsec) &
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((bdev_logical_block_size(preq.bdev) >> 9) - 1)) {
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@ -595,7 +607,9 @@ static int dispatch_rw_block_io(struct blkif_st *blkif,
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goto fail_response;
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}
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}
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/* If we have failed at this point, we need to undo the M2P override,
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/*
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* If we have failed at this point, we need to undo the M2P override,
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* set gnttab_set_unmap_op on all of the grant references and perform
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* the hypercall to unmap the grants - that is all done in
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* xen_blkbk_unmap.
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@ -638,8 +652,8 @@ static int dispatch_rw_block_io(struct blkif_st *blkif,
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bio->bi_end_io = end_block_io_op;
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}
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/* We set it one so that the last submit_bio does not have to call
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/*
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* We set it one so that the last submit_bio does not have to call
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* atomic_inc.
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*/
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atomic_set(&pending_req->pendcnt, nbio);
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@ -47,53 +47,58 @@
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__FILE__ , __LINE__ , ## _a)
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struct vbd {
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blkif_vdev_t handle; /* what the domain refers to this vbd as */
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unsigned char readonly; /* Non-zero -> read-only */
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unsigned char type; /* VDISK_xxx */
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u32 pdevice; /* phys device that this vbd maps to */
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struct block_device *bdev;
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sector_t size; /* Cached size parameter */
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bool flush_support;
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/* What the domain refers to this vbd as. */
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blkif_vdev_t handle;
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/* Non-zero -> read-only */
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unsigned char readonly;
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/* VDISK_xxx */
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unsigned char type;
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/* phys device that this vbd maps to. */
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u32 pdevice;
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struct block_device *bdev;
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/* Cached size parameter. */
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sector_t size;
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bool flush_support;
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};
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struct backend_info;
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struct blkif_st {
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/* Unique identifier for this interface. */
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domid_t domid;
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unsigned int handle;
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domid_t domid;
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unsigned int handle;
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/* Physical parameters of the comms window. */
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unsigned int irq;
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unsigned int irq;
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/* Comms information. */
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enum blkif_protocol blk_protocol;
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union blkif_back_rings blk_rings;
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struct vm_struct *blk_ring_area;
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enum blkif_protocol blk_protocol;
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union blkif_back_rings blk_rings;
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struct vm_struct *blk_ring_area;
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/* The VBD attached to this interface. */
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struct vbd vbd;
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struct vbd vbd;
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/* Back pointer to the backend_info. */
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struct backend_info *be;
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struct backend_info *be;
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/* Private fields. */
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spinlock_t blk_ring_lock;
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atomic_t refcnt;
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spinlock_t blk_ring_lock;
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atomic_t refcnt;
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wait_queue_head_t wq;
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wait_queue_head_t wq;
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/* One thread per one blkif. */
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struct task_struct *xenblkd;
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unsigned int waiting_reqs;
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struct task_struct *xenblkd;
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unsigned int waiting_reqs;
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/* statistics */
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unsigned long st_print;
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int st_rd_req;
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int st_wr_req;
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int st_oo_req;
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int st_f_req;
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int st_rd_sect;
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int st_wr_sect;
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unsigned long st_print;
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int st_rd_req;
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int st_wr_req;
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int st_oo_req;
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int st_f_req;
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int st_rd_sect;
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int st_wr_sect;
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wait_queue_head_t waiting_to_free;
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wait_queue_head_t waiting_to_free;
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grant_handle_t shmem_handle;
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grant_ref_t shmem_ref;
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grant_handle_t shmem_handle;
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grant_ref_t shmem_ref;
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};
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@ -109,10 +114,10 @@ struct blkif_st {
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} while (0)
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struct phys_req {
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unsigned short dev;
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unsigned short nr_sects;
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struct block_device *bdev;
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blkif_sector_t sector_number;
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unsigned short dev;
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unsigned short nr_sects;
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struct block_device *bdev;
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blkif_sector_t sector_number;
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};
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int xen_blkif_interface_init(void);
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@ -27,12 +27,12 @@
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__func__, __LINE__, ##args)
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struct backend_info {
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struct xenbus_device *dev;
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struct blkif_st *blkif;
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struct xenbus_watch backend_watch;
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unsigned major;
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unsigned minor;
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char *mode;
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struct xenbus_device *dev;
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struct blkif_st *blkif;
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struct xenbus_watch backend_watch;
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unsigned major;
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unsigned minor;
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char *mode;
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};
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static struct kmem_cache *xen_blkif_cachep;
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@ -425,7 +425,7 @@ int xen_blkbk_flush_diskcache(struct xenbus_transaction xbt,
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return err;
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}
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/**
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/*
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* Entry point to this code when a new device is created. Allocate the basic
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* structures, and watch the store waiting for the hotplug scripts to tell us
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* the device's physical major and minor numbers. Switch to InitWait.
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@ -473,7 +473,7 @@ fail:
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}
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/**
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/*
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* Callback received when the hotplug scripts have placed the physical-device
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* node. Read it and the mode node, and create a vbd. If the frontend is
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* ready, connect.
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@ -495,9 +495,11 @@ static void backend_changed(struct xenbus_watch *watch,
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err = xenbus_scanf(XBT_NIL, dev->nodename, "physical-device", "%x:%x",
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&major, &minor);
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if (XENBUS_EXIST_ERR(err)) {
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/* Since this watch will fire once immediately after it is
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registered, we expect this. Ignore it, and wait for the
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hotplug scripts. */
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/*
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* Since this watch will fire once immediately after it is
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* registered, we expect this. Ignore it, and wait for the
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* hotplug scripts.
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*/
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return;
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}
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if (err != 2) {
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@ -562,7 +564,7 @@ static void backend_changed(struct xenbus_watch *watch,
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}
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/**
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/*
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* Callback received when the frontend's state changes.
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*/
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static void frontend_changed(struct xenbus_device *dev,
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@ -584,13 +586,16 @@ static void frontend_changed(struct xenbus_device *dev,
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case XenbusStateInitialised:
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case XenbusStateConnected:
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/* Ensure we connect even when two watches fire in
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close successsion and we miss the intermediate value
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of frontend_state. */
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/*
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* Ensure we connect even when two watches fire in
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* close successsion and we miss the intermediate value
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* of frontend_state.
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*/
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if (dev->state == XenbusStateConnected)
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break;
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/* Enforce precondition before potential leak point.
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/*
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* Enforce precondition before potential leak point.
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* blkif_disconnect() is idempotent.
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*/
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xen_blkif_disconnect(be->blkif);
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@ -627,7 +632,7 @@ static void frontend_changed(struct xenbus_device *dev,
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/* ** Connection ** */
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/**
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/*
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* Write the physical details regarding the block device to the store, and
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* switch to Connected state.
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*/
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