X-Git-Url: https://git.camperquake.de/gitweb.cgi?a=blobdiff_plain;f=module%2Fzfs%2Fzpl_file.c;h=9c27b7f1d3b2f614a0e996f980da858780ab8548;hb=b01615d5ac86913da1e092d0378bfb8f0e72af30;hp=c8a3fedb7c8e7ba9719b29f1d760b1854067313d;hpb=81e97e21872a9c38ad66c37fafe1436ee25abee3;p=zfs.git diff --git a/module/zfs/zpl_file.c b/module/zfs/zpl_file.c index c8a3fed..9c27b7f 100644 --- a/module/zfs/zpl_file.c +++ b/module/zfs/zpl_file.c @@ -76,18 +76,78 @@ zpl_readdir(struct file *filp, void *dirent, filldir_t filldir) return (error); } -ZPL_FSYNC_PROTO(zpl_fsync, filp, unused_dentry, datasync) +#if defined(HAVE_FSYNC_WITH_DENTRY) +/* + * Linux 2.6.x - 2.6.34 API, + * Through 2.6.34 the nfsd kernel server would pass a NULL 'file struct *' + * to the fops->fsync() hook. For this reason, we must be careful not to + * use filp unconditionally. + */ +static int +zpl_fsync(struct file *filp, struct dentry *dentry, int datasync) +{ + cred_t *cr = CRED(); + int error; + + crhold(cr); + error = -zfs_fsync(dentry->d_inode, datasync, cr); + crfree(cr); + ASSERT3S(error, <=, 0); + + return (error); +} + +#elif 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; + + crhold(cr); + error = -zfs_fsync(inode, datasync, cr); + crfree(cr); + ASSERT3S(error, <=, 0); + + return (error); +} + +#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; + error = filemap_write_and_wait_range(inode->i_mapping, start, end); + if (error) + return (error); + crhold(cr); - error = -zfs_fsync(filp->f_path.dentry->d_inode, datasync, cr); + error = -zfs_fsync(inode, datasync, cr); crfree(cr); ASSERT3S(error, <=, 0); return (error); } +#else +#error "Unsupported fops->fsync() implementation" +#endif ssize_t zpl_read_common(struct inode *ip, const char *buf, size_t len, loff_t pos, @@ -221,9 +281,15 @@ zpl_write(struct file *filp, const char __user *buf, size_t len, loff_t *ppos) static int zpl_mmap(struct file *filp, struct vm_area_struct *vma) { - znode_t *zp = ITOZ(filp->f_mapping->host); + struct inode *ip = filp->f_mapping->host; + znode_t *zp = ITOZ(ip); int error; + error = -zfs_map(ip, vma->vm_pgoff, (caddr_t *)vma->vm_start, + (size_t)(vma->vm_end - vma->vm_start), vma->vm_flags); + if (error) + return (error); + error = generic_file_mmap(filp, vma); if (error) return (error); @@ -248,33 +314,14 @@ static int zpl_readpage(struct file *filp, struct page *pp) { struct inode *ip; - loff_t off, i_size; - size_t len, wrote; - cred_t *cr = CRED(); - void *pb; + struct page *pl[1]; int error = 0; ASSERT(PageLocked(pp)); ip = pp->mapping->host; - off = page_offset(pp); - i_size = i_size_read(ip); - ASSERT3S(off, <, i_size); - - crhold(cr); - len = MIN(PAGE_CACHE_SIZE, i_size - off); - - pb = kmap(pp); - - /* O_DIRECT is passed to bypass the page cache and avoid deadlock. */ - wrote = zpl_read_common(ip, pb, len, off, UIO_SYSSPACE, O_DIRECT, cr); - if (wrote != len) - error = -EIO; + pl[0] = pp; - if (!error && (len < PAGE_CACHE_SIZE)) - memset(pb + len, 0, PAGE_CACHE_SIZE - len); - - kunmap(pp); - crfree(cr); + error = -zfs_getpage(ip, pl, 1); if (error) { SetPageError(pp); @@ -286,8 +333,48 @@ zpl_readpage(struct file *filp, struct page *pp) } unlock_page(pp); + return error; +} - 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)); +} + +int +zpl_putpage(struct page *pp, struct writeback_control *wbc, void *data) +{ + struct address_space *mapping = data; + + ASSERT(PageLocked(pp)); + ASSERT(!PageWriteback(pp)); + ASSERT(!(current->flags & PF_NOFS)); + + /* + * Annotate this call path with a flag that indicates that it is + * unsafe to use KM_SLEEP during memory allocations due to the + * potential for a deadlock. KM_PUSHPAGE should be used instead. + */ + current->flags |= PF_NOFS; + (void) zfs_putpage(mapping->host, pp, wbc); + current->flags &= ~PF_NOFS; + + return (0); +} + +static int +zpl_writepages(struct address_space *mapping, struct writeback_control *wbc) +{ + return write_cache_pages(mapping, wbc, zpl_putpage, mapping); } /* @@ -295,55 +382,62 @@ zpl_readpage(struct file *filp, struct page *pp) * 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. - * - * Currently this function relies on zpl_write_common() and the O_DIRECT - * flag to push out the page. This works but the more correct way is - * to update zfs_putapage() to be Linux friendly and use that interface. */ static int zpl_writepage(struct page *pp, struct writeback_control *wbc) { - struct inode *ip; - loff_t off, i_size; - size_t len, read; + return zpl_putpage(pp, wbc, pp->mapping); +} + +/* + * The only flag combination which matches the behavior of zfs_space() + * is FALLOC_FL_PUNCH_HOLE. This flag was introduced in the 2.6.38 kernel. + */ +long +zpl_fallocate_common(struct inode *ip, int mode, loff_t offset, loff_t len) +{ cred_t *cr = CRED(); - void *pb; - int error = 0; + int error = -EOPNOTSUPP; - ASSERT(PageLocked(pp)); - ip = pp->mapping->host; - off = page_offset(pp); - i_size = i_size_read(ip); + if (mode & FALLOC_FL_KEEP_SIZE) + return (-EOPNOTSUPP); crhold(cr); - len = MIN(PAGE_CACHE_SIZE, i_size - off); - - pb = kmap(pp); - /* O_DIRECT is passed to bypass the page cache and avoid deadlock. */ - read = zpl_write_common(ip, pb, len, off, UIO_SYSSPACE, O_DIRECT, cr); - if (read != len) - error = -EIO; +#ifdef FALLOC_FL_PUNCH_HOLE + if (mode & FALLOC_FL_PUNCH_HOLE) { + flock64_t bf; - kunmap(pp); - crfree(cr); + bf.l_type = F_WRLCK; + bf.l_whence = 0; + bf.l_start = offset; + bf.l_len = len; + bf.l_pid = 0; - if (error) { - SetPageError(pp); - ClearPageUptodate(pp); - } else { - ClearPageError(pp); - SetPageUptodate(pp); + error = -zfs_space(ip, F_FREESP, &bf, FWRITE, offset, cr); } +#endif /* FALLOC_FL_PUNCH_HOLE */ - unlock_page(pp); + crfree(cr); + ASSERT3S(error, <=, 0); return (error); } +#ifdef HAVE_FILE_FALLOCATE +static long +zpl_fallocate(struct file *filp, int mode, loff_t offset, loff_t len) +{ + return zpl_fallocate_common(filp->f_path.dentry->d_inode, + mode, offset, len); +} +#endif /* HAVE_FILE_FALLOCATE */ + const struct address_space_operations zpl_address_space_operations = { + .readpages = zpl_readpages, .readpage = zpl_readpage, .writepage = zpl_writepage, + .writepages = zpl_writepages, }; const struct file_operations zpl_file_operations = { @@ -355,6 +449,9 @@ const struct file_operations zpl_file_operations = { .readdir = zpl_readdir, .mmap = zpl_mmap, .fsync = zpl_fsync, +#ifdef HAVE_FILE_FALLOCATE + .fallocate = zpl_fallocate, +#endif /* HAVE_FILE_FALLOCATE */ }; const struct file_operations zpl_dir_file_operations = {