diff options
Diffstat (limited to 'module/os/linux/zfs/zpl_file.c')
| -rw-r--r-- | module/os/linux/zfs/zpl_file.c | 1079 |
1 files changed, 1079 insertions, 0 deletions
diff --git a/module/os/linux/zfs/zpl_file.c b/module/os/linux/zfs/zpl_file.c new file mode 100644 index 000000000000..51e189a87272 --- /dev/null +++ b/module/os/linux/zfs/zpl_file.c @@ -0,0 +1,1079 @@ +/* + * 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; + + ZFS_ENTER(zfsvfs); + if (zfsvfs->z_os->os_sync == ZFS_SYNC_ALWAYS) + wbc->sync_mode = WB_SYNC_ALL; + ZFS_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) { + ZFS_ENTER(zfsvfs); + ZFS_VERIFY_ZP(zp); + if (zfsvfs->z_log != NULL) + zil_commit(zfsvfs->z_log, zp->z_id); + ZFS_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 */ |