From 57ae840077e6c061bc57fb4860491f50b604d360 Mon Sep 17 00:00:00 2001 From: Matus Kral Date: Tue, 12 May 2015 01:26:18 +0200 Subject: [PATCH] Linux 4.1 compat: use read_iter() / write_iter() Linux 3.15 commit torvalds/linux@293bc98 introduced two new methods. The ->read_iter() and ->write_iter() methods were designed to replace the ->aio_read() and ->aio_write() interfaces. Both interfaces were preserved for several kernel releases in order to migrate all existing consumers to the new interfaces. But as of Linux 4.1 the legacy interface has been retired and the ZFS code must be updated to use the new interfaces. Signed-off-by: Brian Behlendorf Closes #3352 --- config/kernel-vfs-rw-iterate.m4 | 27 ++++++++++++++++++ config/kernel.m4 | 1 + module/zfs/zpl_file.c | 50 +++++++++++++++++++++++++++------ 3 files changed, 70 insertions(+), 8 deletions(-) create mode 100644 config/kernel-vfs-rw-iterate.m4 diff --git a/config/kernel-vfs-rw-iterate.m4 b/config/kernel-vfs-rw-iterate.m4 new file mode 100644 index 0000000000..f8dc422296 --- /dev/null +++ b/config/kernel-vfs-rw-iterate.m4 @@ -0,0 +1,27 @@ +dnl # +dnl # Linux 4.1.x API +dnl # +AC_DEFUN([ZFS_AC_KERNEL_VFS_RW_ITERATE], + [AC_MSG_CHECKING([whether fops->read/write_iter() are available]) + ZFS_LINUX_TRY_COMPILE([ + #include + + ssize_t test_read(struct kiocb *kiocb, struct iov_iter *to) + { return 0; } + ssize_t test_write(struct kiocb *kiocb, struct iov_iter *from) + { return 0; } + + static const struct file_operations + fops __attribute__ ((unused)) = { + .read_iter = test_read, + .write_iter = test_write, + }; + ],[ + ],[ + AC_MSG_RESULT(yes) + AC_DEFINE(HAVE_VFS_RW_ITERATE, 1, + [fops->read/write_iter() are available]) + ],[ + AC_MSG_RESULT(no) + ]) +]) diff --git a/config/kernel.m4 b/config/kernel.m4 index a9f2f58984..fe42e171ec 100644 --- a/config/kernel.m4 +++ b/config/kernel.m4 @@ -96,6 +96,7 @@ AC_DEFUN([ZFS_AC_CONFIG_KERNEL], [ ZFS_AC_KERNEL_5ARG_SGET ZFS_AC_KERNEL_LSEEK_EXECUTE ZFS_AC_KERNEL_VFS_ITERATE + ZFS_AC_KERNEL_VFS_RW_ITERATE AS_IF([test "$LINUX_OBJ" != "$LINUX"], [ KERNELMAKE_PARAMS="$KERNELMAKE_PARAMS O=$LINUX_OBJ" diff --git a/module/zfs/zpl_file.c b/module/zfs/zpl_file.c index 66db113064..5471140122 100644 --- a/module/zfs/zpl_file.c +++ b/module/zfs/zpl_file.c @@ -196,8 +196,7 @@ zpl_fsync(struct file *filp, loff_t start, loff_t end, int datasync) static int zpl_aio_fsync(struct kiocb *kiocb, int datasync) { - return (zpl_fsync(kiocb->ki_filp, kiocb->ki_pos, - kiocb->ki_pos + kiocb->ki_nbytes, datasync)); + return (zpl_fsync(kiocb->ki_filp, kiocb->ki_pos, -1, datasync)); } #else #error "Unsupported fops->fsync() implementation" @@ -261,12 +260,11 @@ zpl_read(struct file *filp, char __user *buf, size_t len, loff_t *ppos) } static ssize_t -zpl_aio_read(struct kiocb *kiocb, const struct iovec *iovp, - unsigned long nr_segs, loff_t pos) +zpl_iter_read_common(struct kiocb *kiocb, const struct iovec *iovp, + unsigned long nr_segs, size_t count) { cred_t *cr = CRED(); struct file *filp = kiocb->ki_filp; - size_t count = kiocb->ki_nbytes; ssize_t read; size_t alloc_size = sizeof (struct iovec) * nr_segs; struct iovec *iov_tmp = kmem_alloc(alloc_size, KM_SLEEP); @@ -284,6 +282,22 @@ zpl_aio_read(struct kiocb *kiocb, const struct iovec *iovp, return (read); } +#if defined(HAVE_VFS_RW_ITERATE) +static ssize_t +zpl_iter_read(struct kiocb *kiocb, struct iov_iter *to) +{ + return (zpl_iter_read_common(kiocb, to->iov, to->nr_segs, + iov_iter_count(to))); +} +#else +static ssize_t +zpl_aio_read(struct kiocb *kiocb, const struct iovec *iovp, + unsigned long nr_segs, loff_t pos) +{ + return (zpl_iter_read_common(kiocb, iovp, nr_segs, kiocb->ki_nbytes)); +} +#endif /* HAVE_VFS_RW_ITERATE */ + static inline ssize_t zpl_write_common_iovec(struct inode *ip, const struct iovec *iovp, size_t count, unsigned long nr_segs, loff_t *ppos, uio_seg_t segment, @@ -344,12 +358,11 @@ zpl_write(struct file *filp, const char __user *buf, size_t len, loff_t *ppos) } static ssize_t -zpl_aio_write(struct kiocb *kiocb, const struct iovec *iovp, - unsigned long nr_segs, loff_t pos) +zpl_iter_write_common(struct kiocb *kiocb, const struct iovec *iovp, + unsigned long nr_segs, size_t count) { cred_t *cr = CRED(); struct file *filp = kiocb->ki_filp; - size_t count = kiocb->ki_nbytes; ssize_t wrote; size_t alloc_size = sizeof (struct iovec) * nr_segs; struct iovec *iov_tmp = kmem_alloc(alloc_size, KM_SLEEP); @@ -367,6 +380,22 @@ zpl_aio_write(struct kiocb *kiocb, const struct iovec *iovp, return (wrote); } +#if defined(HAVE_VFS_RW_ITERATE) +static ssize_t +zpl_iter_write(struct kiocb *kiocb, struct iov_iter *from) +{ + return (zpl_iter_write_common(kiocb, from->iov, from->nr_segs, + iov_iter_count(from))); +} +#else +static ssize_t +zpl_aio_write(struct kiocb *kiocb, const struct iovec *iovp, + unsigned long nr_segs, loff_t pos) +{ + return (zpl_iter_write_common(kiocb, iovp, nr_segs, kiocb->ki_nbytes)); +} +#endif /* HAVE_VFS_RW_ITERATE */ + static loff_t zpl_llseek(struct file *filp, loff_t offset, int whence) { @@ -778,8 +807,13 @@ const struct file_operations zpl_file_operations = { .llseek = zpl_llseek, .read = zpl_read, .write = zpl_write, +#ifdef HAVE_VFS_RW_ITERATE + .read_iter = zpl_iter_read, + .write_iter = zpl_iter_write, +#else .aio_read = zpl_aio_read, .aio_write = zpl_aio_write, +#endif .mmap = zpl_mmap, .fsync = zpl_fsync, .aio_fsync = zpl_aio_fsync,