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| author | Dan Williams <dan.j.williams@intel.com> | 2018-03-16 17:36:44 -0700 |
|---|---|---|
| committer | Dan Williams <dan.j.williams@intel.com> | 2018-05-22 23:18:31 -0700 |
| commit | a77d478642f12ade58fdfac335ae464df1944a1e (patch) | |
| tree | 1d4597c7dc0e90d457d9fc49f57deef20b34d7bd /fs/dax.c | |
| parent | b3a9a0c36e1f7b9e2e6cf965c2bb973624f2b3b9 (diff) | |
| download | linux-a77d478642f12ade58fdfac335ae464df1944a1e.tar.gz | |
dax: Report bytes remaining in dax_iomap_actor()
In preparation for protecting the dax read(2) path from media errors with copy_to_iter_mcsafe() (via dax_copy_to_iter()), convert the implementation to report the bytes successfully transferred. Cc: <x86@kernel.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Tony Luck <tony.luck@intel.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Diffstat (limited to 'fs/dax.c')
| -rw-r--r-- | fs/dax.c | 20 |
1 files changed, 11 insertions, 9 deletions
diff --git a/fs/dax.c b/fs/dax.c index a64afdf7ec0d..34a2d435ae4b 100644 --- a/fs/dax.c +++ b/fs/dax.c @@ -991,6 +991,7 @@ dax_iomap_actor(struct inode *inode, loff_t pos, loff_t length, void *data, struct iov_iter *iter = data; loff_t end = pos + length, done = 0; ssize_t ret = 0; + size_t xfer; int id; if (iov_iter_rw(iter) == READ) { @@ -1054,19 +1055,20 @@ dax_iomap_actor(struct inode *inode, loff_t pos, loff_t length, void *data, * vfs_write(), depending on which operation we are doing. */ if (iov_iter_rw(iter) == WRITE) - map_len = dax_copy_from_iter(dax_dev, pgoff, kaddr, + xfer = dax_copy_from_iter(dax_dev, pgoff, kaddr, map_len, iter); else - map_len = dax_copy_to_iter(dax_dev, pgoff, kaddr, + xfer = dax_copy_to_iter(dax_dev, pgoff, kaddr, map_len, iter); - if (map_len <= 0) { - ret = map_len ? map_len : -EFAULT; - break; - } - pos += map_len; - length -= map_len; - done += map_len; + pos += xfer; + length -= xfer; + done += xfer; + + if (xfer == 0) + ret = -EFAULT; + if (xfer < map_len) + break; } dax_read_unlock(id); |