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author | Linus Torvalds <torvalds@linux-foundation.org> | 2017-11-17 12:08:18 -0800 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2017-11-17 12:08:18 -0800 |
commit | 16382e17c0ff583df2d5eed56ca7c771d637e9d1 (patch) | |
tree | 568c5a69b55d08cda20b8e1367df3135dbafeeb6 /drivers/vhost/scsi.c | |
parent | 93f30c73ecd0281cf3685ef0e4e384980a176176 (diff) | |
parent | cfe057f7db1ff026c8db75469a3f9ba9736e1975 (diff) | |
download | linux-stable-16382e17c0ff583df2d5eed56ca7c771d637e9d1.tar.gz linux-stable-16382e17c0ff583df2d5eed56ca7c771d637e9d1.tar.bz2 linux-stable-16382e17c0ff583df2d5eed56ca7c771d637e9d1.zip |
Merge branch 'work.iov_iter' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull iov_iter updates from Al Viro:
- bio_{map,copy}_user_iov() series; those are cleanups - fixes from the
same pile went into mainline (and stable) in late September.
- fs/iomap.c iov_iter-related fixes
- new primitive - iov_iter_for_each_range(), which applies a function
to kernel-mapped segments of an iov_iter.
Usable for kvec and bvec ones, the latter does kmap()/kunmap() around
the callback. _Not_ usable for iovec- or pipe-backed iov_iter; the
latter is not hard to fix if the need ever appears, the former is by
design.
Another related primitive will have to wait for the next cycle - it
passes page + offset + size instead of pointer + size, and that one
will be usable for everything _except_ kvec. Unfortunately, that one
didn't get exposure in -next yet, so...
- a bit more lustre iov_iter work, including a use case for
iov_iter_for_each_range() (checksum calculation)
- vhost/scsi leak fix in failure exit
- misc cleanups and detritectomy...
* 'work.iov_iter' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (21 commits)
iomap_dio_actor(): fix iov_iter bugs
switch ksocknal_lib_recv_...() to use of iov_iter_for_each_range()
lustre: switch struct ksock_conn to iov_iter
vhost/scsi: switch to iov_iter_get_pages()
fix a page leak in vhost_scsi_iov_to_sgl() error recovery
new primitive: iov_iter_for_each_range()
lnet_return_rx_credits_locked: don't abuse list_entry
xen: don't open-code iov_iter_kvec()
orangefs: remove detritus from struct orangefs_kiocb_s
kill iov_shorten()
bio_alloc_map_data(): do bmd->iter setup right there
bio_copy_user_iov(): saner bio size calculation
bio_map_user_iov(): get rid of copying iov_iter
bio_copy_from_iter(): get rid of copying iov_iter
move more stuff down into bio_copy_user_iov()
blk_rq_map_user_iov(): move iov_iter_advance() down
bio_map_user_iov(): get rid of the iov_for_each()
bio_map_user_iov(): move alignment check into the main loop
don't rely upon subsequent bio_add_pc_page() calls failing
... and with iov_iter_get_pages_alloc() it becomes even simpler
...
Diffstat (limited to 'drivers/vhost/scsi.c')
-rw-r--r-- | drivers/vhost/scsi.c | 73 |
1 files changed, 23 insertions, 50 deletions
diff --git a/drivers/vhost/scsi.c b/drivers/vhost/scsi.c index 1bc9be829fb4..71517b3c5558 100644 --- a/drivers/vhost/scsi.c +++ b/drivers/vhost/scsi.c @@ -210,12 +210,6 @@ static struct workqueue_struct *vhost_scsi_workqueue; static DEFINE_MUTEX(vhost_scsi_mutex); static LIST_HEAD(vhost_scsi_list); -static int iov_num_pages(void __user *iov_base, size_t iov_len) -{ - return (PAGE_ALIGN((unsigned long)iov_base + iov_len) - - ((unsigned long)iov_base & PAGE_MASK)) >> PAGE_SHIFT; -} - static void vhost_scsi_done_inflight(struct kref *kref) { struct vhost_scsi_inflight *inflight; @@ -618,48 +612,31 @@ vhost_scsi_get_tag(struct vhost_virtqueue *vq, struct vhost_scsi_tpg *tpg, */ static int vhost_scsi_map_to_sgl(struct vhost_scsi_cmd *cmd, - void __user *ptr, - size_t len, + struct iov_iter *iter, struct scatterlist *sgl, bool write) { - unsigned int npages = 0, offset, nbytes; - unsigned int pages_nr = iov_num_pages(ptr, len); - struct scatterlist *sg = sgl; struct page **pages = cmd->tvc_upages; - int ret, i; - - if (pages_nr > VHOST_SCSI_PREALLOC_UPAGES) { - pr_err("vhost_scsi_map_to_sgl() pages_nr: %u greater than" - " preallocated VHOST_SCSI_PREALLOC_UPAGES: %u\n", - pages_nr, VHOST_SCSI_PREALLOC_UPAGES); - return -ENOBUFS; - } + struct scatterlist *sg = sgl; + ssize_t bytes; + size_t offset; + unsigned int npages = 0; - ret = get_user_pages_fast((unsigned long)ptr, pages_nr, write, pages); + bytes = iov_iter_get_pages(iter, pages, LONG_MAX, + VHOST_SCSI_PREALLOC_UPAGES, &offset); /* No pages were pinned */ - if (ret < 0) - goto out; - /* Less pages pinned than wanted */ - if (ret != pages_nr) { - for (i = 0; i < ret; i++) - put_page(pages[i]); - ret = -EFAULT; - goto out; - } + if (bytes <= 0) + return bytes < 0 ? bytes : -EFAULT; - while (len > 0) { - offset = (uintptr_t)ptr & ~PAGE_MASK; - nbytes = min_t(unsigned int, PAGE_SIZE - offset, len); - sg_set_page(sg, pages[npages], nbytes, offset); - ptr += nbytes; - len -= nbytes; - sg++; - npages++; - } + iov_iter_advance(iter, bytes); -out: - return ret; + while (bytes) { + unsigned n = min_t(unsigned, PAGE_SIZE - offset, bytes); + sg_set_page(sg++, pages[npages++], n, offset); + bytes -= n; + offset = 0; + } + return npages; } static int @@ -687,24 +664,20 @@ vhost_scsi_iov_to_sgl(struct vhost_scsi_cmd *cmd, bool write, struct iov_iter *iter, struct scatterlist *sg, int sg_count) { - size_t off = iter->iov_offset; - int i, ret; - - for (i = 0; i < iter->nr_segs; i++) { - void __user *base = iter->iov[i].iov_base + off; - size_t len = iter->iov[i].iov_len - off; + struct scatterlist *p = sg; + int ret; - ret = vhost_scsi_map_to_sgl(cmd, base, len, sg, write); + while (iov_iter_count(iter)) { + ret = vhost_scsi_map_to_sgl(cmd, iter, sg, write); if (ret < 0) { - for (i = 0; i < sg_count; i++) { - struct page *page = sg_page(&sg[i]); + while (p < sg) { + struct page *page = sg_page(p++); if (page) put_page(page); } return ret; } sg += ret; - off = 0; } return 0; } |