11da177e4SLinus Torvalds /* 21da177e4SLinus Torvalds * linux/fs/ext2/file.c 31da177e4SLinus Torvalds * 41da177e4SLinus Torvalds * Copyright (C) 1992, 1993, 1994, 1995 51da177e4SLinus Torvalds * Remy Card (card@masi.ibp.fr) 61da177e4SLinus Torvalds * Laboratoire MASI - Institut Blaise Pascal 71da177e4SLinus Torvalds * Universite Pierre et Marie Curie (Paris VI) 81da177e4SLinus Torvalds * 91da177e4SLinus Torvalds * from 101da177e4SLinus Torvalds * 111da177e4SLinus Torvalds * linux/fs/minix/file.c 121da177e4SLinus Torvalds * 131da177e4SLinus Torvalds * Copyright (C) 1991, 1992 Linus Torvalds 141da177e4SLinus Torvalds * 151da177e4SLinus Torvalds * ext2 fs regular file handling primitives 161da177e4SLinus Torvalds * 171da177e4SLinus Torvalds * 64-bit file support on 64-bit platforms by Jakub Jelinek 181da177e4SLinus Torvalds * (jj@sunsite.ms.mff.cuni.cz) 191da177e4SLinus Torvalds */ 201da177e4SLinus Torvalds 211da177e4SLinus Torvalds #include <linux/time.h> 2248bde86dSJan Kara #include <linux/pagemap.h> 23c94c2acfSMatthew Wilcox #include <linux/dax.h> 24871a2931SChristoph Hellwig #include <linux/quotaops.h> 2525f4e702SChristoph Hellwig #include <linux/iomap.h> 2625f4e702SChristoph Hellwig #include <linux/uio.h> 271da177e4SLinus Torvalds #include "ext2.h" 281da177e4SLinus Torvalds #include "xattr.h" 291da177e4SLinus Torvalds #include "acl.h" 301da177e4SLinus Torvalds 316cd176a5SMatthew Wilcox #ifdef CONFIG_FS_DAX 3225f4e702SChristoph Hellwig static ssize_t ext2_dax_read_iter(struct kiocb *iocb, struct iov_iter *to) 3325f4e702SChristoph Hellwig { 3425f4e702SChristoph Hellwig struct inode *inode = iocb->ki_filp->f_mapping->host; 3525f4e702SChristoph Hellwig ssize_t ret; 3625f4e702SChristoph Hellwig 3725f4e702SChristoph Hellwig if (!iov_iter_count(to)) 3825f4e702SChristoph Hellwig return 0; /* skip atime */ 3925f4e702SChristoph Hellwig 4025f4e702SChristoph Hellwig inode_lock_shared(inode); 4111c59c92SRoss Zwisler ret = dax_iomap_rw(iocb, to, &ext2_iomap_ops); 4225f4e702SChristoph Hellwig inode_unlock_shared(inode); 4325f4e702SChristoph Hellwig 4425f4e702SChristoph Hellwig file_accessed(iocb->ki_filp); 4525f4e702SChristoph Hellwig return ret; 4625f4e702SChristoph Hellwig } 4725f4e702SChristoph Hellwig 4825f4e702SChristoph Hellwig static ssize_t ext2_dax_write_iter(struct kiocb *iocb, struct iov_iter *from) 4925f4e702SChristoph Hellwig { 5025f4e702SChristoph Hellwig struct file *file = iocb->ki_filp; 5125f4e702SChristoph Hellwig struct inode *inode = file->f_mapping->host; 5225f4e702SChristoph Hellwig ssize_t ret; 5325f4e702SChristoph Hellwig 5425f4e702SChristoph Hellwig inode_lock(inode); 5525f4e702SChristoph Hellwig ret = generic_write_checks(iocb, from); 5625f4e702SChristoph Hellwig if (ret <= 0) 5725f4e702SChristoph Hellwig goto out_unlock; 5825f4e702SChristoph Hellwig ret = file_remove_privs(file); 5925f4e702SChristoph Hellwig if (ret) 6025f4e702SChristoph Hellwig goto out_unlock; 6125f4e702SChristoph Hellwig ret = file_update_time(file); 6225f4e702SChristoph Hellwig if (ret) 6325f4e702SChristoph Hellwig goto out_unlock; 6425f4e702SChristoph Hellwig 6511c59c92SRoss Zwisler ret = dax_iomap_rw(iocb, from, &ext2_iomap_ops); 6625f4e702SChristoph Hellwig if (ret > 0 && iocb->ki_pos > i_size_read(inode)) { 6725f4e702SChristoph Hellwig i_size_write(inode, iocb->ki_pos); 6825f4e702SChristoph Hellwig mark_inode_dirty(inode); 6925f4e702SChristoph Hellwig } 7025f4e702SChristoph Hellwig 7125f4e702SChristoph Hellwig out_unlock: 7225f4e702SChristoph Hellwig inode_unlock(inode); 7325f4e702SChristoph Hellwig if (ret > 0) 7425f4e702SChristoph Hellwig ret = generic_write_sync(iocb, ret); 7525f4e702SChristoph Hellwig return ret; 7625f4e702SChristoph Hellwig } 7725f4e702SChristoph Hellwig 785726b27bSRoss Zwisler /* 795726b27bSRoss Zwisler * The lock ordering for ext2 DAX fault paths is: 805726b27bSRoss Zwisler * 815726b27bSRoss Zwisler * mmap_sem (MM) 825726b27bSRoss Zwisler * sb_start_pagefault (vfs, freeze) 835726b27bSRoss Zwisler * ext2_inode_info->dax_sem 845726b27bSRoss Zwisler * address_space->i_mmap_rwsem or page_lock (mutually exclusive in DAX) 855726b27bSRoss Zwisler * ext2_inode_info->truncate_mutex 865726b27bSRoss Zwisler * 875726b27bSRoss Zwisler * The default page_lock and i_size verification done by non-DAX fault paths 885726b27bSRoss Zwisler * is sufficient because ext2 doesn't support hole punching. 895726b27bSRoss Zwisler */ 9011bac800SDave Jiang static int ext2_dax_fault(struct vm_fault *vmf) 91f7ca90b1SMatthew Wilcox { 9211bac800SDave Jiang struct inode *inode = file_inode(vmf->vma->vm_file); 935726b27bSRoss Zwisler struct ext2_inode_info *ei = EXT2_I(inode); 945726b27bSRoss Zwisler int ret; 955726b27bSRoss Zwisler 965726b27bSRoss Zwisler if (vmf->flags & FAULT_FLAG_WRITE) { 975726b27bSRoss Zwisler sb_start_pagefault(inode->i_sb); 9811bac800SDave Jiang file_update_time(vmf->vma->vm_file); 995726b27bSRoss Zwisler } 1005726b27bSRoss Zwisler down_read(&ei->dax_sem); 1015726b27bSRoss Zwisler 102c791ace1SDave Jiang ret = dax_iomap_fault(vmf, PE_SIZE_PTE, &ext2_iomap_ops); 1035726b27bSRoss Zwisler 1045726b27bSRoss Zwisler up_read(&ei->dax_sem); 1055726b27bSRoss Zwisler if (vmf->flags & FAULT_FLAG_WRITE) 1065726b27bSRoss Zwisler sb_end_pagefault(inode->i_sb); 1075726b27bSRoss Zwisler return ret; 108f7ca90b1SMatthew Wilcox } 109f7ca90b1SMatthew Wilcox 11011bac800SDave Jiang static int ext2_dax_pfn_mkwrite(struct vm_fault *vmf) 1115726b27bSRoss Zwisler { 11211bac800SDave Jiang struct inode *inode = file_inode(vmf->vma->vm_file); 1135726b27bSRoss Zwisler struct ext2_inode_info *ei = EXT2_I(inode); 1145726b27bSRoss Zwisler loff_t size; 11580b4adcaSRoss Zwisler int ret; 1165726b27bSRoss Zwisler 1175726b27bSRoss Zwisler sb_start_pagefault(inode->i_sb); 11811bac800SDave Jiang file_update_time(vmf->vma->vm_file); 1195726b27bSRoss Zwisler down_read(&ei->dax_sem); 1205726b27bSRoss Zwisler 1215726b27bSRoss Zwisler /* check that the faulting page hasn't raced with truncate */ 1225726b27bSRoss Zwisler size = (i_size_read(inode) + PAGE_SIZE - 1) >> PAGE_SHIFT; 1235726b27bSRoss Zwisler if (vmf->pgoff >= size) 1245726b27bSRoss Zwisler ret = VM_FAULT_SIGBUS; 12580b4adcaSRoss Zwisler else 12611bac800SDave Jiang ret = dax_pfn_mkwrite(vmf); 1275726b27bSRoss Zwisler 1285726b27bSRoss Zwisler up_read(&ei->dax_sem); 1295726b27bSRoss Zwisler sb_end_pagefault(inode->i_sb); 1305726b27bSRoss Zwisler return ret; 131f7ca90b1SMatthew Wilcox } 132f7ca90b1SMatthew Wilcox 133f7ca90b1SMatthew Wilcox static const struct vm_operations_struct ext2_dax_vm_ops = { 134f7ca90b1SMatthew Wilcox .fault = ext2_dax_fault, 13503e0990fSRoss Zwisler /* 136a2d58167SDave Jiang * .huge_fault is not supported for DAX because allocation in ext2 13703e0990fSRoss Zwisler * cannot be reliably aligned to huge page sizes and so pmd faults 13803e0990fSRoss Zwisler * will always fail and fail back to regular faults. 13903e0990fSRoss Zwisler */ 1401e9d180bSRoss Zwisler .page_mkwrite = ext2_dax_fault, 1415726b27bSRoss Zwisler .pfn_mkwrite = ext2_dax_pfn_mkwrite, 142f7ca90b1SMatthew Wilcox }; 143f7ca90b1SMatthew Wilcox 144f7ca90b1SMatthew Wilcox static int ext2_file_mmap(struct file *file, struct vm_area_struct *vma) 145f7ca90b1SMatthew Wilcox { 146f7ca90b1SMatthew Wilcox if (!IS_DAX(file_inode(file))) 147f7ca90b1SMatthew Wilcox return generic_file_mmap(file, vma); 148f7ca90b1SMatthew Wilcox 149f7ca90b1SMatthew Wilcox file_accessed(file); 150f7ca90b1SMatthew Wilcox vma->vm_ops = &ext2_dax_vm_ops; 15103e0990fSRoss Zwisler vma->vm_flags |= VM_MIXEDMAP; 152f7ca90b1SMatthew Wilcox return 0; 153f7ca90b1SMatthew Wilcox } 154f7ca90b1SMatthew Wilcox #else 155f7ca90b1SMatthew Wilcox #define ext2_file_mmap generic_file_mmap 156f7ca90b1SMatthew Wilcox #endif 157f7ca90b1SMatthew Wilcox 1581da177e4SLinus Torvalds /* 159a6739af8SJan Kara * Called when filp is released. This happens when all file descriptors 160a6739af8SJan Kara * for a single struct file are closed. Note that different open() calls 161a6739af8SJan Kara * for the same file yield different struct file structures. 1621da177e4SLinus Torvalds */ 1631da177e4SLinus Torvalds static int ext2_release_file (struct inode * inode, struct file * filp) 1641da177e4SLinus Torvalds { 165a686cd89SMartin J. Bligh if (filp->f_mode & FMODE_WRITE) { 166a686cd89SMartin J. Bligh mutex_lock(&EXT2_I(inode)->truncate_mutex); 167a686cd89SMartin J. Bligh ext2_discard_reservation(inode); 168a686cd89SMartin J. Bligh mutex_unlock(&EXT2_I(inode)->truncate_mutex); 169a686cd89SMartin J. Bligh } 1701da177e4SLinus Torvalds return 0; 1711da177e4SLinus Torvalds } 1721da177e4SLinus Torvalds 17302c24a82SJosef Bacik int ext2_fsync(struct file *file, loff_t start, loff_t end, int datasync) 17448bde86dSJan Kara { 17548bde86dSJan Kara int ret; 1767ea80859SChristoph Hellwig struct super_block *sb = file->f_mapping->host->i_sb; 17748bde86dSJan Kara struct address_space *mapping = sb->s_bdev->bd_inode->i_mapping; 17848bde86dSJan Kara 17902c24a82SJosef Bacik ret = generic_file_fsync(file, start, end, datasync); 18048bde86dSJan Kara if (ret == -EIO || test_and_clear_bit(AS_EIO, &mapping->flags)) { 18148bde86dSJan Kara /* We don't really know where the IO error happened... */ 18248bde86dSJan Kara ext2_error(sb, __func__, 18348bde86dSJan Kara "detected IO error when writing metadata buffers"); 18448bde86dSJan Kara ret = -EIO; 18548bde86dSJan Kara } 18648bde86dSJan Kara return ret; 18748bde86dSJan Kara } 18848bde86dSJan Kara 18925f4e702SChristoph Hellwig static ssize_t ext2_file_read_iter(struct kiocb *iocb, struct iov_iter *to) 19025f4e702SChristoph Hellwig { 19125f4e702SChristoph Hellwig #ifdef CONFIG_FS_DAX 19225f4e702SChristoph Hellwig if (IS_DAX(iocb->ki_filp->f_mapping->host)) 19325f4e702SChristoph Hellwig return ext2_dax_read_iter(iocb, to); 19425f4e702SChristoph Hellwig #endif 19525f4e702SChristoph Hellwig return generic_file_read_iter(iocb, to); 19625f4e702SChristoph Hellwig } 19725f4e702SChristoph Hellwig 19825f4e702SChristoph Hellwig static ssize_t ext2_file_write_iter(struct kiocb *iocb, struct iov_iter *from) 19925f4e702SChristoph Hellwig { 20025f4e702SChristoph Hellwig #ifdef CONFIG_FS_DAX 20125f4e702SChristoph Hellwig if (IS_DAX(iocb->ki_filp->f_mapping->host)) 20225f4e702SChristoph Hellwig return ext2_dax_write_iter(iocb, from); 20325f4e702SChristoph Hellwig #endif 20425f4e702SChristoph Hellwig return generic_file_write_iter(iocb, from); 20525f4e702SChristoph Hellwig } 20625f4e702SChristoph Hellwig 2074b6f5d20SArjan van de Ven const struct file_operations ext2_file_operations = { 2081da177e4SLinus Torvalds .llseek = generic_file_llseek, 20925f4e702SChristoph Hellwig .read_iter = ext2_file_read_iter, 21025f4e702SChristoph Hellwig .write_iter = ext2_file_write_iter, 21114f9f7b2SAndi Kleen .unlocked_ioctl = ext2_ioctl, 212e322ff07SDavid Howells #ifdef CONFIG_COMPAT 213e322ff07SDavid Howells .compat_ioctl = ext2_compat_ioctl, 214e322ff07SDavid Howells #endif 215f7ca90b1SMatthew Wilcox .mmap = ext2_file_mmap, 216907f4554SChristoph Hellwig .open = dquot_file_open, 2171da177e4SLinus Torvalds .release = ext2_release_file, 21848bde86dSJan Kara .fsync = ext2_fsync, 219dbe6ec81SToshi Kani .get_unmapped_area = thp_get_unmapped_area, 2205274f052SJens Axboe .splice_read = generic_file_splice_read, 2218d020765SAl Viro .splice_write = iter_file_splice_write, 2221da177e4SLinus Torvalds }; 2231da177e4SLinus Torvalds 224754661f1SArjan van de Ven const struct inode_operations ext2_file_inode_operations = { 2251da177e4SLinus Torvalds #ifdef CONFIG_EXT2_FS_XATTR 2261da177e4SLinus Torvalds .listxattr = ext2_listxattr, 2271da177e4SLinus Torvalds #endif 2281da177e4SLinus Torvalds .setattr = ext2_setattr, 2294e34e719SChristoph Hellwig .get_acl = ext2_get_acl, 23064e178a7SChristoph Hellwig .set_acl = ext2_set_acl, 23168c9d702SJosef Bacik .fiemap = ext2_fiemap, 2321da177e4SLinus Torvalds }; 233