1b2441318SGreg Kroah-Hartman // SPDX-License-Identifier: GPL-2.0 21da177e4SLinus Torvalds /* 31da177e4SLinus Torvalds * linux/fs/ext2/file.c 41da177e4SLinus Torvalds * 51da177e4SLinus Torvalds * Copyright (C) 1992, 1993, 1994, 1995 61da177e4SLinus Torvalds * Remy Card (card@masi.ibp.fr) 71da177e4SLinus Torvalds * Laboratoire MASI - Institut Blaise Pascal 81da177e4SLinus Torvalds * Universite Pierre et Marie Curie (Paris VI) 91da177e4SLinus Torvalds * 101da177e4SLinus Torvalds * from 111da177e4SLinus Torvalds * 121da177e4SLinus Torvalds * linux/fs/minix/file.c 131da177e4SLinus Torvalds * 141da177e4SLinus Torvalds * Copyright (C) 1991, 1992 Linus Torvalds 151da177e4SLinus Torvalds * 161da177e4SLinus Torvalds * ext2 fs regular file handling primitives 171da177e4SLinus Torvalds * 181da177e4SLinus Torvalds * 64-bit file support on 64-bit platforms by Jakub Jelinek 191da177e4SLinus Torvalds * (jj@sunsite.ms.mff.cuni.cz) 201da177e4SLinus Torvalds */ 211da177e4SLinus Torvalds 221da177e4SLinus Torvalds #include <linux/time.h> 2348bde86dSJan Kara #include <linux/pagemap.h> 24c94c2acfSMatthew Wilcox #include <linux/dax.h> 25871a2931SChristoph Hellwig #include <linux/quotaops.h> 2625f4e702SChristoph Hellwig #include <linux/iomap.h> 2725f4e702SChristoph Hellwig #include <linux/uio.h> 281da177e4SLinus Torvalds #include "ext2.h" 291da177e4SLinus Torvalds #include "xattr.h" 301da177e4SLinus Torvalds #include "acl.h" 311da177e4SLinus Torvalds 326cd176a5SMatthew Wilcox #ifdef CONFIG_FS_DAX 3325f4e702SChristoph Hellwig static ssize_t ext2_dax_read_iter(struct kiocb *iocb, struct iov_iter *to) 3425f4e702SChristoph Hellwig { 3525f4e702SChristoph Hellwig struct inode *inode = iocb->ki_filp->f_mapping->host; 3625f4e702SChristoph Hellwig ssize_t ret; 3725f4e702SChristoph Hellwig 3825f4e702SChristoph Hellwig if (!iov_iter_count(to)) 3925f4e702SChristoph Hellwig return 0; /* skip atime */ 4025f4e702SChristoph Hellwig 4125f4e702SChristoph Hellwig inode_lock_shared(inode); 4211c59c92SRoss Zwisler ret = dax_iomap_rw(iocb, to, &ext2_iomap_ops); 4325f4e702SChristoph Hellwig inode_unlock_shared(inode); 4425f4e702SChristoph Hellwig 4525f4e702SChristoph Hellwig file_accessed(iocb->ki_filp); 4625f4e702SChristoph Hellwig return ret; 4725f4e702SChristoph Hellwig } 4825f4e702SChristoph Hellwig 4925f4e702SChristoph Hellwig static ssize_t ext2_dax_write_iter(struct kiocb *iocb, struct iov_iter *from) 5025f4e702SChristoph Hellwig { 5125f4e702SChristoph Hellwig struct file *file = iocb->ki_filp; 5225f4e702SChristoph Hellwig struct inode *inode = file->f_mapping->host; 5325f4e702SChristoph Hellwig ssize_t ret; 5425f4e702SChristoph Hellwig 5525f4e702SChristoph Hellwig inode_lock(inode); 5625f4e702SChristoph Hellwig ret = generic_write_checks(iocb, from); 5725f4e702SChristoph Hellwig if (ret <= 0) 5825f4e702SChristoph Hellwig goto out_unlock; 5925f4e702SChristoph Hellwig ret = file_remove_privs(file); 6025f4e702SChristoph Hellwig if (ret) 6125f4e702SChristoph Hellwig goto out_unlock; 6225f4e702SChristoph Hellwig ret = file_update_time(file); 6325f4e702SChristoph Hellwig if (ret) 6425f4e702SChristoph Hellwig goto out_unlock; 6525f4e702SChristoph Hellwig 6611c59c92SRoss Zwisler ret = dax_iomap_rw(iocb, from, &ext2_iomap_ops); 6725f4e702SChristoph Hellwig if (ret > 0 && iocb->ki_pos > i_size_read(inode)) { 6825f4e702SChristoph Hellwig i_size_write(inode, iocb->ki_pos); 6925f4e702SChristoph Hellwig mark_inode_dirty(inode); 7025f4e702SChristoph Hellwig } 7125f4e702SChristoph Hellwig 7225f4e702SChristoph Hellwig out_unlock: 7325f4e702SChristoph Hellwig inode_unlock(inode); 7425f4e702SChristoph Hellwig if (ret > 0) 7525f4e702SChristoph Hellwig ret = generic_write_sync(iocb, ret); 7625f4e702SChristoph Hellwig return ret; 7725f4e702SChristoph Hellwig } 7825f4e702SChristoph Hellwig 795726b27bSRoss Zwisler /* 805726b27bSRoss Zwisler * The lock ordering for ext2 DAX fault paths is: 815726b27bSRoss Zwisler * 82c1e8d7c6SMichel Lespinasse * mmap_lock (MM) 835726b27bSRoss Zwisler * sb_start_pagefault (vfs, freeze) 84*70f3bad8SJan Kara * address_space->invalidate_lock 855726b27bSRoss Zwisler * address_space->i_mmap_rwsem or page_lock (mutually exclusive in DAX) 865726b27bSRoss Zwisler * ext2_inode_info->truncate_mutex 875726b27bSRoss Zwisler * 885726b27bSRoss Zwisler * The default page_lock and i_size verification done by non-DAX fault paths 895726b27bSRoss Zwisler * is sufficient because ext2 doesn't support hole punching. 905726b27bSRoss Zwisler */ 9106856938SSouptick Joarder static vm_fault_t ext2_dax_fault(struct vm_fault *vmf) 92f7ca90b1SMatthew Wilcox { 9311bac800SDave Jiang struct inode *inode = file_inode(vmf->vma->vm_file); 9406856938SSouptick Joarder vm_fault_t ret; 951ef6ea0eSMikulas Patocka bool write = (vmf->flags & FAULT_FLAG_WRITE) && 961ef6ea0eSMikulas Patocka (vmf->vma->vm_flags & VM_SHARED); 975726b27bSRoss Zwisler 981ef6ea0eSMikulas Patocka if (write) { 995726b27bSRoss Zwisler sb_start_pagefault(inode->i_sb); 10011bac800SDave Jiang file_update_time(vmf->vma->vm_file); 1015726b27bSRoss Zwisler } 102*70f3bad8SJan Kara filemap_invalidate_lock_shared(inode->i_mapping); 1035726b27bSRoss Zwisler 104c0b24625SJan Kara ret = dax_iomap_fault(vmf, PE_SIZE_PTE, NULL, NULL, &ext2_iomap_ops); 1055726b27bSRoss Zwisler 106*70f3bad8SJan Kara filemap_invalidate_unlock_shared(inode->i_mapping); 1071ef6ea0eSMikulas Patocka if (write) 1085726b27bSRoss Zwisler sb_end_pagefault(inode->i_sb); 1095726b27bSRoss Zwisler return ret; 110f7ca90b1SMatthew Wilcox } 111f7ca90b1SMatthew Wilcox 112f7ca90b1SMatthew Wilcox static const struct vm_operations_struct ext2_dax_vm_ops = { 113f7ca90b1SMatthew Wilcox .fault = ext2_dax_fault, 11403e0990fSRoss Zwisler /* 115a2d58167SDave Jiang * .huge_fault is not supported for DAX because allocation in ext2 11603e0990fSRoss Zwisler * cannot be reliably aligned to huge page sizes and so pmd faults 11703e0990fSRoss Zwisler * will always fail and fail back to regular faults. 11803e0990fSRoss Zwisler */ 1191e9d180bSRoss Zwisler .page_mkwrite = ext2_dax_fault, 12091d25ba8SRoss Zwisler .pfn_mkwrite = ext2_dax_fault, 121f7ca90b1SMatthew Wilcox }; 122f7ca90b1SMatthew Wilcox 123f7ca90b1SMatthew Wilcox static int ext2_file_mmap(struct file *file, struct vm_area_struct *vma) 124f7ca90b1SMatthew Wilcox { 125f7ca90b1SMatthew Wilcox if (!IS_DAX(file_inode(file))) 126f7ca90b1SMatthew Wilcox return generic_file_mmap(file, vma); 127f7ca90b1SMatthew Wilcox 128f7ca90b1SMatthew Wilcox file_accessed(file); 129f7ca90b1SMatthew Wilcox vma->vm_ops = &ext2_dax_vm_ops; 130f7ca90b1SMatthew Wilcox return 0; 131f7ca90b1SMatthew Wilcox } 132f7ca90b1SMatthew Wilcox #else 133f7ca90b1SMatthew Wilcox #define ext2_file_mmap generic_file_mmap 134f7ca90b1SMatthew Wilcox #endif 135f7ca90b1SMatthew Wilcox 1361da177e4SLinus Torvalds /* 137a6739af8SJan Kara * Called when filp is released. This happens when all file descriptors 138a6739af8SJan Kara * for a single struct file are closed. Note that different open() calls 139a6739af8SJan Kara * for the same file yield different struct file structures. 1401da177e4SLinus Torvalds */ 1411da177e4SLinus Torvalds static int ext2_release_file (struct inode * inode, struct file * filp) 1421da177e4SLinus Torvalds { 143a686cd89SMartin J. Bligh if (filp->f_mode & FMODE_WRITE) { 144a686cd89SMartin J. Bligh mutex_lock(&EXT2_I(inode)->truncate_mutex); 145a686cd89SMartin J. Bligh ext2_discard_reservation(inode); 146a686cd89SMartin J. Bligh mutex_unlock(&EXT2_I(inode)->truncate_mutex); 147a686cd89SMartin J. Bligh } 1481da177e4SLinus Torvalds return 0; 1491da177e4SLinus Torvalds } 1501da177e4SLinus Torvalds 15102c24a82SJosef Bacik int ext2_fsync(struct file *file, loff_t start, loff_t end, int datasync) 15248bde86dSJan Kara { 15348bde86dSJan Kara int ret; 1547ea80859SChristoph Hellwig struct super_block *sb = file->f_mapping->host->i_sb; 15548bde86dSJan Kara 15602c24a82SJosef Bacik ret = generic_file_fsync(file, start, end, datasync); 157dac257f7SJeff Layton if (ret == -EIO) 15848bde86dSJan Kara /* We don't really know where the IO error happened... */ 15948bde86dSJan Kara ext2_error(sb, __func__, 16048bde86dSJan Kara "detected IO error when writing metadata buffers"); 16148bde86dSJan Kara return ret; 16248bde86dSJan Kara } 16348bde86dSJan Kara 16425f4e702SChristoph Hellwig static ssize_t ext2_file_read_iter(struct kiocb *iocb, struct iov_iter *to) 16525f4e702SChristoph Hellwig { 16625f4e702SChristoph Hellwig #ifdef CONFIG_FS_DAX 16725f4e702SChristoph Hellwig if (IS_DAX(iocb->ki_filp->f_mapping->host)) 16825f4e702SChristoph Hellwig return ext2_dax_read_iter(iocb, to); 16925f4e702SChristoph Hellwig #endif 17025f4e702SChristoph Hellwig return generic_file_read_iter(iocb, to); 17125f4e702SChristoph Hellwig } 17225f4e702SChristoph Hellwig 17325f4e702SChristoph Hellwig static ssize_t ext2_file_write_iter(struct kiocb *iocb, struct iov_iter *from) 17425f4e702SChristoph Hellwig { 17525f4e702SChristoph Hellwig #ifdef CONFIG_FS_DAX 17625f4e702SChristoph Hellwig if (IS_DAX(iocb->ki_filp->f_mapping->host)) 17725f4e702SChristoph Hellwig return ext2_dax_write_iter(iocb, from); 17825f4e702SChristoph Hellwig #endif 17925f4e702SChristoph Hellwig return generic_file_write_iter(iocb, from); 18025f4e702SChristoph Hellwig } 18125f4e702SChristoph Hellwig 1824b6f5d20SArjan van de Ven const struct file_operations ext2_file_operations = { 1831da177e4SLinus Torvalds .llseek = generic_file_llseek, 18425f4e702SChristoph Hellwig .read_iter = ext2_file_read_iter, 18525f4e702SChristoph Hellwig .write_iter = ext2_file_write_iter, 18614f9f7b2SAndi Kleen .unlocked_ioctl = ext2_ioctl, 187e322ff07SDavid Howells #ifdef CONFIG_COMPAT 188e322ff07SDavid Howells .compat_ioctl = ext2_compat_ioctl, 189e322ff07SDavid Howells #endif 190f7ca90b1SMatthew Wilcox .mmap = ext2_file_mmap, 191907f4554SChristoph Hellwig .open = dquot_file_open, 1921da177e4SLinus Torvalds .release = ext2_release_file, 19348bde86dSJan Kara .fsync = ext2_fsync, 194dbe6ec81SToshi Kani .get_unmapped_area = thp_get_unmapped_area, 1955274f052SJens Axboe .splice_read = generic_file_splice_read, 1968d020765SAl Viro .splice_write = iter_file_splice_write, 1971da177e4SLinus Torvalds }; 1981da177e4SLinus Torvalds 199754661f1SArjan van de Ven const struct inode_operations ext2_file_inode_operations = { 2001da177e4SLinus Torvalds .listxattr = ext2_listxattr, 20193bc420eSyangerkun .getattr = ext2_getattr, 2021da177e4SLinus Torvalds .setattr = ext2_setattr, 2034e34e719SChristoph Hellwig .get_acl = ext2_get_acl, 20464e178a7SChristoph Hellwig .set_acl = ext2_set_acl, 20568c9d702SJosef Bacik .fiemap = ext2_fiemap, 206aba405e3SMiklos Szeredi .fileattr_get = ext2_fileattr_get, 207aba405e3SMiklos Szeredi .fileattr_set = ext2_fileattr_set, 2081da177e4SLinus Torvalds }; 209