zfs-builds-mm/zfs-2.0.0/module/os/linux/zfs/zpl_file.c

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2020-12-02 17:25:31 +01:00
/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License (the "License").
* You may not use this file except in compliance with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright (c) 2011, Lawrence Livermore National Security, LLC.
* Copyright (c) 2015 by Chunwei Chen. All rights reserved.
*/
#ifdef CONFIG_COMPAT
#include <linux/compat.h>
#endif
#include <sys/file.h>
#include <sys/dmu_objset.h>
#include <sys/zfs_znode.h>
#include <sys/zfs_vfsops.h>
#include <sys/zfs_vnops.h>
#include <sys/zfs_project.h>
/*
* When using fallocate(2) to preallocate space, inflate the requested
* capacity check by 10% to account for the required metadata blocks.
*/
unsigned int zfs_fallocate_reserve_percent = 110;
static int
zpl_open(struct inode *ip, struct file *filp)
{
cred_t *cr = CRED();
int error;
fstrans_cookie_t cookie;
error = generic_file_open(ip, filp);
if (error)
return (error);
crhold(cr);
cookie = spl_fstrans_mark();
error = -zfs_open(ip, filp->f_mode, filp->f_flags, cr);
spl_fstrans_unmark(cookie);
crfree(cr);
ASSERT3S(error, <=, 0);
return (error);
}
static int
zpl_release(struct inode *ip, struct file *filp)
{
cred_t *cr = CRED();
int error;
fstrans_cookie_t cookie;
cookie = spl_fstrans_mark();
if (ITOZ(ip)->z_atime_dirty)
zfs_mark_inode_dirty(ip);
crhold(cr);
error = -zfs_close(ip, filp->f_flags, cr);
spl_fstrans_unmark(cookie);
crfree(cr);
ASSERT3S(error, <=, 0);
return (error);
}
static int
zpl_iterate(struct file *filp, zpl_dir_context_t *ctx)
{
cred_t *cr = CRED();
int error;
fstrans_cookie_t cookie;
crhold(cr);
cookie = spl_fstrans_mark();
error = -zfs_readdir(file_inode(filp), ctx, cr);
spl_fstrans_unmark(cookie);
crfree(cr);
ASSERT3S(error, <=, 0);
return (error);
}
#if !defined(HAVE_VFS_ITERATE) && !defined(HAVE_VFS_ITERATE_SHARED)
static int
zpl_readdir(struct file *filp, void *dirent, filldir_t filldir)
{
zpl_dir_context_t ctx =
ZPL_DIR_CONTEXT_INIT(dirent, filldir, filp->f_pos);
int error;
error = zpl_iterate(filp, &ctx);
filp->f_pos = ctx.pos;
return (error);
}
#endif /* !HAVE_VFS_ITERATE && !HAVE_VFS_ITERATE_SHARED */
#if defined(HAVE_FSYNC_WITHOUT_DENTRY)
/*
* Linux 2.6.35 - 3.0 API,
* As of 2.6.35 the dentry argument to the fops->fsync() hook was deemed
* redundant. The dentry is still accessible via filp->f_path.dentry,
* and we are guaranteed that filp will never be NULL.
*/
static int
zpl_fsync(struct file *filp, int datasync)
{
struct inode *inode = filp->f_mapping->host;
cred_t *cr = CRED();
int error;
fstrans_cookie_t cookie;
crhold(cr);
cookie = spl_fstrans_mark();
error = -zfs_fsync(ITOZ(inode), datasync, cr);
spl_fstrans_unmark(cookie);
crfree(cr);
ASSERT3S(error, <=, 0);
return (error);
}
#ifdef HAVE_FILE_AIO_FSYNC
static int
zpl_aio_fsync(struct kiocb *kiocb, int datasync)
{
return (zpl_fsync(kiocb->ki_filp, datasync));
}
#endif
#elif defined(HAVE_FSYNC_RANGE)
/*
* Linux 3.1 - 3.x API,
* As of 3.1 the responsibility to call filemap_write_and_wait_range() has
* been pushed down in to the .fsync() vfs hook. Additionally, the i_mutex
* lock is no longer held by the caller, for zfs we don't require the lock
* to be held so we don't acquire it.
*/
static int
zpl_fsync(struct file *filp, loff_t start, loff_t end, int datasync)
{
struct inode *inode = filp->f_mapping->host;
cred_t *cr = CRED();
int error;
fstrans_cookie_t cookie;
error = filemap_write_and_wait_range(inode->i_mapping, start, end);
if (error)
return (error);
crhold(cr);
cookie = spl_fstrans_mark();
error = -zfs_fsync(ITOZ(inode), datasync, cr);
spl_fstrans_unmark(cookie);
crfree(cr);
ASSERT3S(error, <=, 0);
return (error);
}
#ifdef HAVE_FILE_AIO_FSYNC
static int
zpl_aio_fsync(struct kiocb *kiocb, int datasync)
{
return (zpl_fsync(kiocb->ki_filp, kiocb->ki_pos, -1, datasync));
}
#endif
#else
#error "Unsupported fops->fsync() implementation"
#endif
static inline int
zfs_io_flags(struct kiocb *kiocb)
{
int flags = 0;
#if defined(IOCB_DSYNC)
if (kiocb->ki_flags & IOCB_DSYNC)
flags |= O_DSYNC;
#endif
#if defined(IOCB_SYNC)
if (kiocb->ki_flags & IOCB_SYNC)
flags |= O_SYNC;
#endif
#if defined(IOCB_APPEND)
if (kiocb->ki_flags & IOCB_APPEND)
flags |= O_APPEND;
#endif
#if defined(IOCB_DIRECT)
if (kiocb->ki_flags & IOCB_DIRECT)
flags |= O_DIRECT;
#endif
return (flags);
}
static ssize_t
zpl_read_common_iovec(struct inode *ip, const struct iovec *iovp, size_t count,
unsigned long nr_segs, loff_t *ppos, uio_seg_t segment, int flags,
cred_t *cr, size_t skip)
{
ssize_t read;
uio_t uio = { { 0 }, 0 };
int error;
fstrans_cookie_t cookie;
uio.uio_iov = iovp;
uio.uio_iovcnt = nr_segs;
uio.uio_loffset = *ppos;
uio.uio_segflg = segment;
uio.uio_limit = MAXOFFSET_T;
uio.uio_resid = count;
uio.uio_skip = skip;
cookie = spl_fstrans_mark();
error = -zfs_read(ip, &uio, flags, cr);
spl_fstrans_unmark(cookie);
if (error < 0)
return (error);
read = count - uio.uio_resid;
*ppos += read;
return (read);
}
inline ssize_t
zpl_read_common(struct inode *ip, const char *buf, size_t len, loff_t *ppos,
uio_seg_t segment, int flags, cred_t *cr)
{
struct iovec iov;
iov.iov_base = (void *)buf;
iov.iov_len = len;
return (zpl_read_common_iovec(ip, &iov, len, 1, ppos, segment,
flags, cr, 0));
}
static ssize_t
zpl_iter_read_common(struct kiocb *kiocb, const struct iovec *iovp,
unsigned long nr_segs, size_t count, uio_seg_t seg, size_t skip)
{
cred_t *cr = CRED();
struct file *filp = kiocb->ki_filp;
struct inode *ip = filp->f_mapping->host;
zfsvfs_t *zfsvfs = ZTOZSB(ITOZ(ip));
ssize_t read;
unsigned int f_flags = filp->f_flags;
f_flags |= zfs_io_flags(kiocb);
crhold(cr);
read = zpl_read_common_iovec(filp->f_mapping->host, iovp, count,
nr_segs, &kiocb->ki_pos, seg, f_flags, cr, skip);
crfree(cr);
/*
* If relatime is enabled, call file_accessed() only if
* zfs_relatime_need_update() is true. This is needed since datasets
* with inherited "relatime" property aren't necessarily mounted with
* MNT_RELATIME flag (e.g. after `zfs set relatime=...`), which is what
* relatime test in VFS by relatime_need_update() is based on.
*/
if (!IS_NOATIME(ip) && zfsvfs->z_relatime) {
if (zfs_relatime_need_update(ip))
file_accessed(filp);
} else {
file_accessed(filp);
}
return (read);
}
#if defined(HAVE_VFS_RW_ITERATE)
static ssize_t
zpl_iter_read(struct kiocb *kiocb, struct iov_iter *to)
{
ssize_t ret;
uio_seg_t seg = UIO_USERSPACE;
if (to->type & ITER_KVEC)
seg = UIO_SYSSPACE;
if (to->type & ITER_BVEC)
seg = UIO_BVEC;
ret = zpl_iter_read_common(kiocb, to->iov, to->nr_segs,
iov_iter_count(to), seg, to->iov_offset);
if (ret > 0)
iov_iter_advance(to, ret);
return (ret);
}
#else
static ssize_t
zpl_aio_read(struct kiocb *kiocb, const struct iovec *iovp,
unsigned long nr_segs, loff_t pos)
{
ssize_t ret;
size_t count;
ret = generic_segment_checks(iovp, &nr_segs, &count, VERIFY_WRITE);
if (ret)
return (ret);
return (zpl_iter_read_common(kiocb, iovp, nr_segs, count,
UIO_USERSPACE, 0));
}
#endif /* HAVE_VFS_RW_ITERATE */
static 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, int flags,
cred_t *cr, size_t skip)
{
ssize_t wrote;
uio_t uio = { { 0 }, 0 };
int error;
fstrans_cookie_t cookie;
if (flags & O_APPEND)
*ppos = i_size_read(ip);
uio.uio_iov = iovp;
uio.uio_iovcnt = nr_segs;
uio.uio_loffset = *ppos;
uio.uio_segflg = segment;
uio.uio_limit = MAXOFFSET_T;
uio.uio_resid = count;
uio.uio_skip = skip;
cookie = spl_fstrans_mark();
error = -zfs_write(ip, &uio, flags, cr);
spl_fstrans_unmark(cookie);
if (error < 0)
return (error);
wrote = count - uio.uio_resid;
*ppos += wrote;
return (wrote);
}
inline ssize_t
zpl_write_common(struct inode *ip, const char *buf, size_t len, loff_t *ppos,
uio_seg_t segment, int flags, cred_t *cr)
{
struct iovec iov;
iov.iov_base = (void *)buf;
iov.iov_len = len;
return (zpl_write_common_iovec(ip, &iov, len, 1, ppos, segment,
flags, cr, 0));
}
static ssize_t
zpl_iter_write_common(struct kiocb *kiocb, const struct iovec *iovp,
unsigned long nr_segs, size_t count, uio_seg_t seg, size_t skip)
{
cred_t *cr = CRED();
struct file *filp = kiocb->ki_filp;
ssize_t wrote;
unsigned int f_flags = filp->f_flags;
f_flags |= zfs_io_flags(kiocb);
crhold(cr);
wrote = zpl_write_common_iovec(filp->f_mapping->host, iovp, count,
nr_segs, &kiocb->ki_pos, seg, f_flags, cr, skip);
crfree(cr);
return (wrote);
}
#if defined(HAVE_VFS_RW_ITERATE)
static ssize_t
zpl_iter_write(struct kiocb *kiocb, struct iov_iter *from)
{
size_t count;
ssize_t ret;
uio_seg_t seg = UIO_USERSPACE;
#ifndef HAVE_GENERIC_WRITE_CHECKS_KIOCB
struct file *file = kiocb->ki_filp;
struct address_space *mapping = file->f_mapping;
struct inode *ip = mapping->host;
int isblk = S_ISBLK(ip->i_mode);
count = iov_iter_count(from);
ret = generic_write_checks(file, &kiocb->ki_pos, &count, isblk);
if (ret)
return (ret);
#else
/*
* XXX - ideally this check should be in the same lock region with
* write operations, so that there's no TOCTTOU race when doing
* append and someone else grow the file.
*/
ret = generic_write_checks(kiocb, from);
if (ret <= 0)
return (ret);
count = ret;
#endif
if (from->type & ITER_KVEC)
seg = UIO_SYSSPACE;
if (from->type & ITER_BVEC)
seg = UIO_BVEC;
ret = zpl_iter_write_common(kiocb, from->iov, from->nr_segs,
count, seg, from->iov_offset);
if (ret > 0)
iov_iter_advance(from, ret);
return (ret);
}
#else
static ssize_t
zpl_aio_write(struct kiocb *kiocb, const struct iovec *iovp,
unsigned long nr_segs, loff_t pos)
{
struct file *file = kiocb->ki_filp;
struct address_space *mapping = file->f_mapping;
struct inode *ip = mapping->host;
int isblk = S_ISBLK(ip->i_mode);
size_t count;
ssize_t ret;
ret = generic_segment_checks(iovp, &nr_segs, &count, VERIFY_READ);
if (ret)
return (ret);
ret = generic_write_checks(file, &pos, &count, isblk);
if (ret)
return (ret);
return (zpl_iter_write_common(kiocb, iovp, nr_segs, count,
UIO_USERSPACE, 0));
}
#endif /* HAVE_VFS_RW_ITERATE */
#if defined(HAVE_VFS_RW_ITERATE)
static ssize_t
zpl_direct_IO_impl(int rw, struct kiocb *kiocb, struct iov_iter *iter)
{
if (rw == WRITE)
return (zpl_iter_write(kiocb, iter));
else
return (zpl_iter_read(kiocb, iter));
}
#if defined(HAVE_VFS_DIRECT_IO_ITER)
static ssize_t
zpl_direct_IO(struct kiocb *kiocb, struct iov_iter *iter)
{
return (zpl_direct_IO_impl(iov_iter_rw(iter), kiocb, iter));
}
#elif defined(HAVE_VFS_DIRECT_IO_ITER_OFFSET)
static ssize_t
zpl_direct_IO(struct kiocb *kiocb, struct iov_iter *iter, loff_t pos)
{
ASSERT3S(pos, ==, kiocb->ki_pos);
return (zpl_direct_IO_impl(iov_iter_rw(iter), kiocb, iter));
}
#elif defined(HAVE_VFS_DIRECT_IO_ITER_RW_OFFSET)
static ssize_t
zpl_direct_IO(int rw, struct kiocb *kiocb, struct iov_iter *iter, loff_t pos)
{
ASSERT3S(pos, ==, kiocb->ki_pos);
return (zpl_direct_IO_impl(rw, kiocb, iter));
}
#else
#error "Unknown direct IO interface"
#endif
#else
#if defined(HAVE_VFS_DIRECT_IO_IOVEC)
static ssize_t
zpl_direct_IO(int rw, struct kiocb *kiocb, const struct iovec *iovp,
loff_t pos, unsigned long nr_segs)
{
if (rw == WRITE)
return (zpl_aio_write(kiocb, iovp, nr_segs, pos));
else
return (zpl_aio_read(kiocb, iovp, nr_segs, pos));
}
#else
#error "Unknown direct IO interface"
#endif
#endif /* HAVE_VFS_RW_ITERATE */
static loff_t
zpl_llseek(struct file *filp, loff_t offset, int whence)
{
#if defined(SEEK_HOLE) && defined(SEEK_DATA)
fstrans_cookie_t cookie;
if (whence == SEEK_DATA || whence == SEEK_HOLE) {
struct inode *ip = filp->f_mapping->host;
loff_t maxbytes = ip->i_sb->s_maxbytes;
loff_t error;
spl_inode_lock_shared(ip);
cookie = spl_fstrans_mark();
error = -zfs_holey(ip, whence, &offset);
spl_fstrans_unmark(cookie);
if (error == 0)
error = lseek_execute(filp, ip, offset, maxbytes);
spl_inode_unlock_shared(ip);
return (error);
}
#endif /* SEEK_HOLE && SEEK_DATA */
return (generic_file_llseek(filp, offset, whence));
}
/*
* It's worth taking a moment to describe how mmap is implemented
* for zfs because it differs considerably from other Linux filesystems.
* However, this issue is handled the same way under OpenSolaris.
*
* The issue is that by design zfs bypasses the Linux page cache and
* leaves all caching up to the ARC. This has been shown to work
* well for the common read(2)/write(2) case. However, mmap(2)
* is problem because it relies on being tightly integrated with the
* page cache. To handle this we cache mmap'ed files twice, once in
* the ARC and a second time in the page cache. The code is careful
* to keep both copies synchronized.
*
* When a file with an mmap'ed region is written to using write(2)
* both the data in the ARC and existing pages in the page cache
* are updated. For a read(2) data will be read first from the page
* cache then the ARC if needed. Neither a write(2) or read(2) will
* will ever result in new pages being added to the page cache.
*
* New pages are added to the page cache only via .readpage() which
* is called when the vfs needs to read a page off disk to back the
* virtual memory region. These pages may be modified without
* notifying the ARC and will be written out periodically via
* .writepage(). This will occur due to either a sync or the usual
* page aging behavior. Note because a read(2) of a mmap'ed file
* will always check the page cache first even when the ARC is out
* of date correct data will still be returned.
*
* While this implementation ensures correct behavior it does have
* have some drawbacks. The most obvious of which is that it
* increases the required memory footprint when access mmap'ed
* files. It also adds additional complexity to the code keeping
* both caches synchronized.
*
* Longer term it may be possible to cleanly resolve this wart by
* mapping page cache pages directly on to the ARC buffers. The
* Linux address space operations are flexible enough to allow
* selection of which pages back a particular index. The trick
* would be working out the details of which subsystem is in
* charge, the ARC, the page cache, or both. It may also prove
* helpful to move the ARC buffers to a scatter-gather lists
* rather than a vmalloc'ed region.
*/
static int
zpl_mmap(struct file *filp, struct vm_area_struct *vma)
{
struct inode *ip = filp->f_mapping->host;
znode_t *zp = ITOZ(ip);
int error;
fstrans_cookie_t cookie;
cookie = spl_fstrans_mark();
error = -zfs_map(ip, vma->vm_pgoff, (caddr_t *)vma->vm_start,
(size_t)(vma->vm_end - vma->vm_start), vma->vm_flags);
spl_fstrans_unmark(cookie);
if (error)
return (error);
error = generic_file_mmap(filp, vma);
if (error)
return (error);
mutex_enter(&zp->z_lock);
zp->z_is_mapped = B_TRUE;
mutex_exit(&zp->z_lock);
return (error);
}
/*
* Populate a page with data for the Linux page cache. This function is
* only used to support mmap(2). There will be an identical copy of the
* data in the ARC which is kept up to date via .write() and .writepage().
*
* Current this function relies on zpl_read_common() and the O_DIRECT
* flag to read in a page. This works but the more correct way is to
* update zfs_fillpage() to be Linux friendly and use that interface.
*/
static int
zpl_readpage(struct file *filp, struct page *pp)
{
struct inode *ip;
struct page *pl[1];
int error = 0;
fstrans_cookie_t cookie;
ASSERT(PageLocked(pp));
ip = pp->mapping->host;
pl[0] = pp;
cookie = spl_fstrans_mark();
error = -zfs_getpage(ip, pl, 1);
spl_fstrans_unmark(cookie);
if (error) {
SetPageError(pp);
ClearPageUptodate(pp);
} else {
ClearPageError(pp);
SetPageUptodate(pp);
flush_dcache_page(pp);
}
unlock_page(pp);
return (error);
}
/*
* Populate a set of pages with data for the Linux page cache. This
* function will only be called for read ahead and never for demand
* paging. For simplicity, the code relies on read_cache_pages() to
* correctly lock each page for IO and call zpl_readpage().
*/
static int
zpl_readpages(struct file *filp, struct address_space *mapping,
struct list_head *pages, unsigned nr_pages)
{
return (read_cache_pages(mapping, pages,
(filler_t *)zpl_readpage, filp));
}
static int
zpl_putpage(struct page *pp, struct writeback_control *wbc, void *data)
{
struct address_space *mapping = data;
fstrans_cookie_t cookie;
ASSERT(PageLocked(pp));
ASSERT(!PageWriteback(pp));
cookie = spl_fstrans_mark();
(void) zfs_putpage(mapping->host, pp, wbc);
spl_fstrans_unmark(cookie);
return (0);
}
static int
zpl_writepages(struct address_space *mapping, struct writeback_control *wbc)
{
znode_t *zp = ITOZ(mapping->host);
zfsvfs_t *zfsvfs = ITOZSB(mapping->host);
enum writeback_sync_modes sync_mode;
int result;
ZPL_ENTER(zfsvfs);
if (zfsvfs->z_os->os_sync == ZFS_SYNC_ALWAYS)
wbc->sync_mode = WB_SYNC_ALL;
ZPL_EXIT(zfsvfs);
sync_mode = wbc->sync_mode;
/*
* We don't want to run write_cache_pages() in SYNC mode here, because
* that would make putpage() wait for a single page to be committed to
* disk every single time, resulting in atrocious performance. Instead
* we run it once in non-SYNC mode so that the ZIL gets all the data,
* and then we commit it all in one go.
*/
wbc->sync_mode = WB_SYNC_NONE;
result = write_cache_pages(mapping, wbc, zpl_putpage, mapping);
if (sync_mode != wbc->sync_mode) {
ZPL_ENTER(zfsvfs);
ZPL_VERIFY_ZP(zp);
if (zfsvfs->z_log != NULL)
zil_commit(zfsvfs->z_log, zp->z_id);
ZPL_EXIT(zfsvfs);
/*
* We need to call write_cache_pages() again (we can't just
* return after the commit) because the previous call in
* non-SYNC mode does not guarantee that we got all the dirty
* pages (see the implementation of write_cache_pages() for
* details). That being said, this is a no-op in most cases.
*/
wbc->sync_mode = sync_mode;
result = write_cache_pages(mapping, wbc, zpl_putpage, mapping);
}
return (result);
}
/*
* Write out dirty pages to the ARC, this function is only required to
* support mmap(2). Mapped pages may be dirtied by memory operations
* which never call .write(). These dirty pages are kept in sync with
* the ARC buffers via this hook.
*/
static int
zpl_writepage(struct page *pp, struct writeback_control *wbc)
{
if (ITOZSB(pp->mapping->host)->z_os->os_sync == ZFS_SYNC_ALWAYS)
wbc->sync_mode = WB_SYNC_ALL;
return (zpl_putpage(pp, wbc, pp->mapping));
}
/*
* The flag combination which matches the behavior of zfs_space() is
* FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE. The FALLOC_FL_PUNCH_HOLE
* flag was introduced in the 2.6.38 kernel.
*
* The original mode=0 (allocate space) behavior can be reasonably emulated
* by checking if enough space exists and creating a sparse file, as real
* persistent space reservation is not possible due to COW, snapshots, etc.
*/
static long
zpl_fallocate_common(struct inode *ip, int mode, loff_t offset, loff_t len)
{
cred_t *cr = CRED();
loff_t olen;
fstrans_cookie_t cookie;
int error = 0;
if ((mode & ~(FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE)) != 0)
return (-EOPNOTSUPP);
if (offset < 0 || len <= 0)
return (-EINVAL);
spl_inode_lock(ip);
olen = i_size_read(ip);
crhold(cr);
cookie = spl_fstrans_mark();
if (mode & FALLOC_FL_PUNCH_HOLE) {
flock64_t bf;
if (offset > olen)
goto out_unmark;
if (offset + len > olen)
len = olen - offset;
bf.l_type = F_WRLCK;
bf.l_whence = SEEK_SET;
bf.l_start = offset;
bf.l_len = len;
bf.l_pid = 0;
error = -zfs_space(ITOZ(ip), F_FREESP, &bf, O_RDWR, offset, cr);
} else if ((mode & ~FALLOC_FL_KEEP_SIZE) == 0) {
unsigned int percent = zfs_fallocate_reserve_percent;
struct kstatfs statfs;
/* Legacy mode, disable fallocate compatibility. */
if (percent == 0) {
error = -EOPNOTSUPP;
goto out_unmark;
}
/*
* Use zfs_statvfs() instead of dmu_objset_space() since it
* also checks project quota limits, which are relevant here.
*/
error = zfs_statvfs(ip, &statfs);
if (error)
goto out_unmark;
/*
* Shrink available space a bit to account for overhead/races.
* We know the product previously fit into availbytes from
* dmu_objset_space(), so the smaller product will also fit.
*/
if (len > statfs.f_bavail * (statfs.f_bsize * 100 / percent)) {
error = -ENOSPC;
goto out_unmark;
}
if (!(mode & FALLOC_FL_KEEP_SIZE) && offset + len > olen)
error = zfs_freesp(ITOZ(ip), offset + len, 0, 0, FALSE);
}
out_unmark:
spl_fstrans_unmark(cookie);
spl_inode_unlock(ip);
crfree(cr);
return (error);
}
static long
zpl_fallocate(struct file *filp, int mode, loff_t offset, loff_t len)
{
return zpl_fallocate_common(file_inode(filp),
mode, offset, len);
}
#define ZFS_FL_USER_VISIBLE (FS_FL_USER_VISIBLE | ZFS_PROJINHERIT_FL)
#define ZFS_FL_USER_MODIFIABLE (FS_FL_USER_MODIFIABLE | ZFS_PROJINHERIT_FL)
static uint32_t
__zpl_ioctl_getflags(struct inode *ip)
{
uint64_t zfs_flags = ITOZ(ip)->z_pflags;
uint32_t ioctl_flags = 0;
if (zfs_flags & ZFS_IMMUTABLE)
ioctl_flags |= FS_IMMUTABLE_FL;
if (zfs_flags & ZFS_APPENDONLY)
ioctl_flags |= FS_APPEND_FL;
if (zfs_flags & ZFS_NODUMP)
ioctl_flags |= FS_NODUMP_FL;
if (zfs_flags & ZFS_PROJINHERIT)
ioctl_flags |= ZFS_PROJINHERIT_FL;
return (ioctl_flags & ZFS_FL_USER_VISIBLE);
}
/*
* Map zfs file z_pflags (xvattr_t) to linux file attributes. Only file
* attributes common to both Linux and Solaris are mapped.
*/
static int
zpl_ioctl_getflags(struct file *filp, void __user *arg)
{
uint32_t flags;
int err;
flags = __zpl_ioctl_getflags(file_inode(filp));
err = copy_to_user(arg, &flags, sizeof (flags));
return (err);
}
/*
* fchange() is a helper macro to detect if we have been asked to change a
* flag. This is ugly, but the requirement that we do this is a consequence of
* how the Linux file attribute interface was designed. Another consequence is
* that concurrent modification of files suffers from a TOCTOU race. Neither
* are things we can fix without modifying the kernel-userland interface, which
* is outside of our jurisdiction.
*/
#define fchange(f0, f1, b0, b1) (!((f0) & (b0)) != !((f1) & (b1)))
static int
__zpl_ioctl_setflags(struct inode *ip, uint32_t ioctl_flags, xvattr_t *xva)
{
uint64_t zfs_flags = ITOZ(ip)->z_pflags;
xoptattr_t *xoap;
if (ioctl_flags & ~(FS_IMMUTABLE_FL | FS_APPEND_FL | FS_NODUMP_FL |
ZFS_PROJINHERIT_FL))
return (-EOPNOTSUPP);
if (ioctl_flags & ~ZFS_FL_USER_MODIFIABLE)
return (-EACCES);
if ((fchange(ioctl_flags, zfs_flags, FS_IMMUTABLE_FL, ZFS_IMMUTABLE) ||
fchange(ioctl_flags, zfs_flags, FS_APPEND_FL, ZFS_APPENDONLY)) &&
!capable(CAP_LINUX_IMMUTABLE))
return (-EACCES);
if (!inode_owner_or_capable(ip))
return (-EACCES);
xva_init(xva);
xoap = xva_getxoptattr(xva);
XVA_SET_REQ(xva, XAT_IMMUTABLE);
if (ioctl_flags & FS_IMMUTABLE_FL)
xoap->xoa_immutable = B_TRUE;
XVA_SET_REQ(xva, XAT_APPENDONLY);
if (ioctl_flags & FS_APPEND_FL)
xoap->xoa_appendonly = B_TRUE;
XVA_SET_REQ(xva, XAT_NODUMP);
if (ioctl_flags & FS_NODUMP_FL)
xoap->xoa_nodump = B_TRUE;
XVA_SET_REQ(xva, XAT_PROJINHERIT);
if (ioctl_flags & ZFS_PROJINHERIT_FL)
xoap->xoa_projinherit = B_TRUE;
return (0);
}
static int
zpl_ioctl_setflags(struct file *filp, void __user *arg)
{
struct inode *ip = file_inode(filp);
uint32_t flags;
cred_t *cr = CRED();
xvattr_t xva;
int err;
fstrans_cookie_t cookie;
if (copy_from_user(&flags, arg, sizeof (flags)))
return (-EFAULT);
err = __zpl_ioctl_setflags(ip, flags, &xva);
if (err)
return (err);
crhold(cr);
cookie = spl_fstrans_mark();
err = -zfs_setattr(ITOZ(ip), (vattr_t *)&xva, 0, cr);
spl_fstrans_unmark(cookie);
crfree(cr);
return (err);
}
static int
zpl_ioctl_getxattr(struct file *filp, void __user *arg)
{
zfsxattr_t fsx = { 0 };
struct inode *ip = file_inode(filp);
int err;
fsx.fsx_xflags = __zpl_ioctl_getflags(ip);
fsx.fsx_projid = ITOZ(ip)->z_projid;
err = copy_to_user(arg, &fsx, sizeof (fsx));
return (err);
}
static int
zpl_ioctl_setxattr(struct file *filp, void __user *arg)
{
struct inode *ip = file_inode(filp);
zfsxattr_t fsx;
cred_t *cr = CRED();
xvattr_t xva;
xoptattr_t *xoap;
int err;
fstrans_cookie_t cookie;
if (copy_from_user(&fsx, arg, sizeof (fsx)))
return (-EFAULT);
if (!zpl_is_valid_projid(fsx.fsx_projid))
return (-EINVAL);
err = __zpl_ioctl_setflags(ip, fsx.fsx_xflags, &xva);
if (err)
return (err);
xoap = xva_getxoptattr(&xva);
XVA_SET_REQ(&xva, XAT_PROJID);
xoap->xoa_projid = fsx.fsx_projid;
crhold(cr);
cookie = spl_fstrans_mark();
err = -zfs_setattr(ITOZ(ip), (vattr_t *)&xva, 0, cr);
spl_fstrans_unmark(cookie);
crfree(cr);
return (err);
}
static long
zpl_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
{
switch (cmd) {
case FS_IOC_GETFLAGS:
return (zpl_ioctl_getflags(filp, (void *)arg));
case FS_IOC_SETFLAGS:
return (zpl_ioctl_setflags(filp, (void *)arg));
case ZFS_IOC_FSGETXATTR:
return (zpl_ioctl_getxattr(filp, (void *)arg));
case ZFS_IOC_FSSETXATTR:
return (zpl_ioctl_setxattr(filp, (void *)arg));
default:
return (-ENOTTY);
}
}
#ifdef CONFIG_COMPAT
static long
zpl_compat_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
{
switch (cmd) {
case FS_IOC32_GETFLAGS:
cmd = FS_IOC_GETFLAGS;
break;
case FS_IOC32_SETFLAGS:
cmd = FS_IOC_SETFLAGS;
break;
default:
return (-ENOTTY);
}
return (zpl_ioctl(filp, cmd, (unsigned long)compat_ptr(arg)));
}
#endif /* CONFIG_COMPAT */
const struct address_space_operations zpl_address_space_operations = {
.readpages = zpl_readpages,
.readpage = zpl_readpage,
.writepage = zpl_writepage,
.writepages = zpl_writepages,
.direct_IO = zpl_direct_IO,
};
const struct file_operations zpl_file_operations = {
.open = zpl_open,
.release = zpl_release,
.llseek = zpl_llseek,
#ifdef HAVE_VFS_RW_ITERATE
#ifdef HAVE_NEW_SYNC_READ
.read = new_sync_read,
.write = new_sync_write,
#endif
.read_iter = zpl_iter_read,
.write_iter = zpl_iter_write,
#else
.read = do_sync_read,
.write = do_sync_write,
.aio_read = zpl_aio_read,
.aio_write = zpl_aio_write,
#endif
.mmap = zpl_mmap,
.fsync = zpl_fsync,
#ifdef HAVE_FILE_AIO_FSYNC
.aio_fsync = zpl_aio_fsync,
#endif
.fallocate = zpl_fallocate,
.unlocked_ioctl = zpl_ioctl,
#ifdef CONFIG_COMPAT
.compat_ioctl = zpl_compat_ioctl,
#endif
};
const struct file_operations zpl_dir_file_operations = {
.llseek = generic_file_llseek,
.read = generic_read_dir,
#if defined(HAVE_VFS_ITERATE_SHARED)
.iterate_shared = zpl_iterate,
#elif defined(HAVE_VFS_ITERATE)
.iterate = zpl_iterate,
#else
.readdir = zpl_readdir,
#endif
.fsync = zpl_fsync,
.unlocked_ioctl = zpl_ioctl,
#ifdef CONFIG_COMPAT
.compat_ioctl = zpl_compat_ioctl,
#endif
};
/* BEGIN CSTYLED */
module_param(zfs_fallocate_reserve_percent, uint, 0644);
MODULE_PARM_DESC(zfs_fallocate_reserve_percent,
"Percentage of length to use for the available capacity check");
/* END CSTYLED */