diff options
Diffstat (limited to 'module')
| -rw-r--r-- | module/zcommon/zfs_uio.c | 31 | ||||
| -rw-r--r-- | module/zfs/zfs_vnops.c | 24 |
2 files changed, 46 insertions, 9 deletions
diff --git a/module/zcommon/zfs_uio.c b/module/zcommon/zfs_uio.c index af9716126..a2c1b5c3a 100644 --- a/module/zcommon/zfs_uio.c +++ b/module/zcommon/zfs_uio.c @@ -52,6 +52,7 @@ #include <sys/sysmacros.h> #include <sys/strings.h> #include <linux/kmap_compat.h> +#include <linux/uaccess.h> /* * Move "n" bytes at byte address "p"; "rw" indicates the direction @@ -79,8 +80,24 @@ uiomove_iov(void *p, size_t n, enum uio_rw rw, struct uio *uio) if (copy_to_user(iov->iov_base+skip, p, cnt)) return (EFAULT); } else { - if (copy_from_user(p, iov->iov_base+skip, cnt)) - return (EFAULT); + if (uio->uio_fault_disable) { + if (!access_ok(VERIFY_READ, + (iov->iov_base + skip), cnt)) { + return (EFAULT); + } + + pagefault_disable(); + if (__copy_from_user_inatomic(p, + (iov->iov_base + skip), cnt)) { + pagefault_enable(); + return (EFAULT); + } + pagefault_enable(); + } else { + if (copy_from_user(p, + (iov->iov_base + skip), cnt)) + return (EFAULT); + } } break; case UIO_SYSSPACE: @@ -158,7 +175,7 @@ EXPORT_SYMBOL(uiomove); * error will terminate the process as this is only a best attempt to get * the pages resident. */ -void +int uio_prefaultpages(ssize_t n, struct uio *uio) { const struct iovec *iov; @@ -172,7 +189,7 @@ uio_prefaultpages(ssize_t n, struct uio *uio) switch (uio->uio_segflg) { case UIO_SYSSPACE: case UIO_BVEC: - return; + return (0); case UIO_USERSPACE: case UIO_USERISPACE: break; @@ -196,7 +213,7 @@ uio_prefaultpages(ssize_t n, struct uio *uio) p = iov->iov_base + skip; while (cnt) { if (fuword8((uint8_t *)p, &tmp)) - return; + return (EFAULT); incr = MIN(cnt, PAGESIZE); p += incr; cnt -= incr; @@ -206,8 +223,10 @@ uio_prefaultpages(ssize_t n, struct uio *uio) */ p--; if (fuword8((uint8_t *)p, &tmp)) - return; + return (EFAULT); } + + return (0); } EXPORT_SYMBOL(uio_prefaultpages); diff --git a/module/zfs/zfs_vnops.c b/module/zfs/zfs_vnops.c index 36f47e77a..f4e650dee 100644 --- a/module/zfs/zfs_vnops.c +++ b/module/zfs/zfs_vnops.c @@ -650,7 +650,10 @@ zfs_write(struct inode *ip, uio_t *uio, int ioflag, cred_t *cr) xuio = (xuio_t *)uio; else #endif - uio_prefaultpages(MIN(n, max_blksz), uio); + if (uio_prefaultpages(MIN(n, max_blksz), uio)) { + ZFS_EXIT(zfsvfs); + return (SET_ERROR(EFAULT)); + } /* * If in append mode, set the io offset pointer to eof. @@ -808,8 +811,19 @@ zfs_write(struct inode *ip, uio_t *uio, int ioflag, cred_t *cr) ssize_t tx_bytes; if (abuf == NULL) { tx_bytes = uio->uio_resid; + uio->uio_fault_disable = B_TRUE; error = dmu_write_uio_dbuf(sa_get_db(zp->z_sa_hdl), uio, nbytes, tx); + if (error == EFAULT) { + dmu_tx_commit(tx); + if (uio_prefaultpages(MIN(n, max_blksz), uio)) { + break; + } + continue; + } else if (error != 0) { + dmu_tx_commit(tx); + break; + } tx_bytes -= uio->uio_resid; } else { tx_bytes = nbytes; @@ -909,8 +923,12 @@ zfs_write(struct inode *ip, uio_t *uio, int ioflag, cred_t *cr) ASSERT(tx_bytes == nbytes); n -= nbytes; - if (!xuio && n > 0) - uio_prefaultpages(MIN(n, max_blksz), uio); + if (!xuio && n > 0) { + if (uio_prefaultpages(MIN(n, max_blksz), uio)) { + error = EFAULT; + break; + } + } } zfs_inode_update(zp); |