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); 4125f4e702SChristoph Hellwig ret = iomap_dax_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 6525f4e702SChristoph Hellwig ret = iomap_dax_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 */ 90f7ca90b1SMatthew Wilcox static int ext2_dax_fault(struct vm_area_struct *vma, struct vm_fault *vmf) 91f7ca90b1SMatthew Wilcox { 925726b27bSRoss Zwisler struct inode *inode = file_inode(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); 985726b27bSRoss Zwisler file_update_time(vma->vm_file); 995726b27bSRoss Zwisler } 1005726b27bSRoss Zwisler down_read(&ei->dax_sem); 1015726b27bSRoss Zwisler 10225f4e702SChristoph Hellwig ret = iomap_dax_fault(vma, vmf, &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 110e7b1ea2aSMatthew Wilcox static int ext2_dax_pmd_fault(struct vm_area_struct *vma, unsigned long addr, 111e7b1ea2aSMatthew Wilcox pmd_t *pmd, unsigned int flags) 112e7b1ea2aSMatthew Wilcox { 1135726b27bSRoss Zwisler struct inode *inode = file_inode(vma->vm_file); 1145726b27bSRoss Zwisler struct ext2_inode_info *ei = EXT2_I(inode); 1155726b27bSRoss Zwisler int ret; 1165726b27bSRoss Zwisler 1175726b27bSRoss Zwisler if (flags & FAULT_FLAG_WRITE) { 1185726b27bSRoss Zwisler sb_start_pagefault(inode->i_sb); 1195726b27bSRoss Zwisler file_update_time(vma->vm_file); 1205726b27bSRoss Zwisler } 1215726b27bSRoss Zwisler down_read(&ei->dax_sem); 1225726b27bSRoss Zwisler 1236b524995SRoss Zwisler ret = dax_pmd_fault(vma, addr, pmd, flags, ext2_get_block); 1245726b27bSRoss Zwisler 1255726b27bSRoss Zwisler up_read(&ei->dax_sem); 1265726b27bSRoss Zwisler if (flags & FAULT_FLAG_WRITE) 1275726b27bSRoss Zwisler sb_end_pagefault(inode->i_sb); 1285726b27bSRoss Zwisler return ret; 129e7b1ea2aSMatthew Wilcox } 130e7b1ea2aSMatthew Wilcox 1315726b27bSRoss Zwisler static int ext2_dax_pfn_mkwrite(struct vm_area_struct *vma, 1325726b27bSRoss Zwisler struct vm_fault *vmf) 1335726b27bSRoss Zwisler { 1345726b27bSRoss Zwisler struct inode *inode = file_inode(vma->vm_file); 1355726b27bSRoss Zwisler struct ext2_inode_info *ei = EXT2_I(inode); 1365726b27bSRoss Zwisler loff_t size; 13780b4adcaSRoss Zwisler int ret; 1385726b27bSRoss Zwisler 1395726b27bSRoss Zwisler sb_start_pagefault(inode->i_sb); 1405726b27bSRoss Zwisler file_update_time(vma->vm_file); 1415726b27bSRoss Zwisler down_read(&ei->dax_sem); 1425726b27bSRoss Zwisler 1435726b27bSRoss Zwisler /* check that the faulting page hasn't raced with truncate */ 1445726b27bSRoss Zwisler size = (i_size_read(inode) + PAGE_SIZE - 1) >> PAGE_SHIFT; 1455726b27bSRoss Zwisler if (vmf->pgoff >= size) 1465726b27bSRoss Zwisler ret = VM_FAULT_SIGBUS; 14780b4adcaSRoss Zwisler else 14880b4adcaSRoss Zwisler ret = dax_pfn_mkwrite(vma, vmf); 1495726b27bSRoss Zwisler 1505726b27bSRoss Zwisler up_read(&ei->dax_sem); 1515726b27bSRoss Zwisler sb_end_pagefault(inode->i_sb); 1525726b27bSRoss Zwisler return ret; 153f7ca90b1SMatthew Wilcox } 154f7ca90b1SMatthew Wilcox 155f7ca90b1SMatthew Wilcox static const struct vm_operations_struct ext2_dax_vm_ops = { 156f7ca90b1SMatthew Wilcox .fault = ext2_dax_fault, 157e7b1ea2aSMatthew Wilcox .pmd_fault = ext2_dax_pmd_fault, 1581e9d180bSRoss Zwisler .page_mkwrite = ext2_dax_fault, 1595726b27bSRoss Zwisler .pfn_mkwrite = ext2_dax_pfn_mkwrite, 160f7ca90b1SMatthew Wilcox }; 161f7ca90b1SMatthew Wilcox 162f7ca90b1SMatthew Wilcox static int ext2_file_mmap(struct file *file, struct vm_area_struct *vma) 163f7ca90b1SMatthew Wilcox { 164f7ca90b1SMatthew Wilcox if (!IS_DAX(file_inode(file))) 165f7ca90b1SMatthew Wilcox return generic_file_mmap(file, vma); 166f7ca90b1SMatthew Wilcox 167f7ca90b1SMatthew Wilcox file_accessed(file); 168f7ca90b1SMatthew Wilcox vma->vm_ops = &ext2_dax_vm_ops; 169e7b1ea2aSMatthew Wilcox vma->vm_flags |= VM_MIXEDMAP | VM_HUGEPAGE; 170f7ca90b1SMatthew Wilcox return 0; 171f7ca90b1SMatthew Wilcox } 172f7ca90b1SMatthew Wilcox #else 173f7ca90b1SMatthew Wilcox #define ext2_file_mmap generic_file_mmap 174f7ca90b1SMatthew Wilcox #endif 175f7ca90b1SMatthew Wilcox 1761da177e4SLinus Torvalds /* 177a6739af8SJan Kara * Called when filp is released. This happens when all file descriptors 178a6739af8SJan Kara * for a single struct file are closed. Note that different open() calls 179a6739af8SJan Kara * for the same file yield different struct file structures. 1801da177e4SLinus Torvalds */ 1811da177e4SLinus Torvalds static int ext2_release_file (struct inode * inode, struct file * filp) 1821da177e4SLinus Torvalds { 183a686cd89SMartin J. Bligh if (filp->f_mode & FMODE_WRITE) { 184a686cd89SMartin J. Bligh mutex_lock(&EXT2_I(inode)->truncate_mutex); 185a686cd89SMartin J. Bligh ext2_discard_reservation(inode); 186a686cd89SMartin J. Bligh mutex_unlock(&EXT2_I(inode)->truncate_mutex); 187a686cd89SMartin J. Bligh } 1881da177e4SLinus Torvalds return 0; 1891da177e4SLinus Torvalds } 1901da177e4SLinus Torvalds 19102c24a82SJosef Bacik int ext2_fsync(struct file *file, loff_t start, loff_t end, int datasync) 19248bde86dSJan Kara { 19348bde86dSJan Kara int ret; 1947ea80859SChristoph Hellwig struct super_block *sb = file->f_mapping->host->i_sb; 19548bde86dSJan Kara struct address_space *mapping = sb->s_bdev->bd_inode->i_mapping; 19648bde86dSJan Kara 19702c24a82SJosef Bacik ret = generic_file_fsync(file, start, end, datasync); 19848bde86dSJan Kara if (ret == -EIO || test_and_clear_bit(AS_EIO, &mapping->flags)) { 19948bde86dSJan Kara /* We don't really know where the IO error happened... */ 20048bde86dSJan Kara ext2_error(sb, __func__, 20148bde86dSJan Kara "detected IO error when writing metadata buffers"); 20248bde86dSJan Kara ret = -EIO; 20348bde86dSJan Kara } 20448bde86dSJan Kara return ret; 20548bde86dSJan Kara } 20648bde86dSJan Kara 20725f4e702SChristoph Hellwig static ssize_t ext2_file_read_iter(struct kiocb *iocb, struct iov_iter *to) 20825f4e702SChristoph Hellwig { 20925f4e702SChristoph Hellwig #ifdef CONFIG_FS_DAX 21025f4e702SChristoph Hellwig if (IS_DAX(iocb->ki_filp->f_mapping->host)) 21125f4e702SChristoph Hellwig return ext2_dax_read_iter(iocb, to); 21225f4e702SChristoph Hellwig #endif 21325f4e702SChristoph Hellwig return generic_file_read_iter(iocb, to); 21425f4e702SChristoph Hellwig } 21525f4e702SChristoph Hellwig 21625f4e702SChristoph Hellwig static ssize_t ext2_file_write_iter(struct kiocb *iocb, struct iov_iter *from) 21725f4e702SChristoph Hellwig { 21825f4e702SChristoph Hellwig #ifdef CONFIG_FS_DAX 21925f4e702SChristoph Hellwig if (IS_DAX(iocb->ki_filp->f_mapping->host)) 22025f4e702SChristoph Hellwig return ext2_dax_write_iter(iocb, from); 22125f4e702SChristoph Hellwig #endif 22225f4e702SChristoph Hellwig return generic_file_write_iter(iocb, from); 22325f4e702SChristoph Hellwig } 22425f4e702SChristoph Hellwig 2254b6f5d20SArjan van de Ven const struct file_operations ext2_file_operations = { 2261da177e4SLinus Torvalds .llseek = generic_file_llseek, 22725f4e702SChristoph Hellwig .read_iter = ext2_file_read_iter, 22825f4e702SChristoph Hellwig .write_iter = ext2_file_write_iter, 22914f9f7b2SAndi Kleen .unlocked_ioctl = ext2_ioctl, 230e322ff07SDavid Howells #ifdef CONFIG_COMPAT 231e322ff07SDavid Howells .compat_ioctl = ext2_compat_ioctl, 232e322ff07SDavid Howells #endif 233f7ca90b1SMatthew Wilcox .mmap = ext2_file_mmap, 234907f4554SChristoph Hellwig .open = dquot_file_open, 2351da177e4SLinus Torvalds .release = ext2_release_file, 23648bde86dSJan Kara .fsync = ext2_fsync, 2375274f052SJens Axboe .splice_read = generic_file_splice_read, 2388d020765SAl Viro .splice_write = iter_file_splice_write, 2391da177e4SLinus Torvalds }; 2401da177e4SLinus Torvalds 241754661f1SArjan van de Ven const struct inode_operations ext2_file_inode_operations = { 2421da177e4SLinus Torvalds #ifdef CONFIG_EXT2_FS_XATTR 2431da177e4SLinus Torvalds .setxattr = generic_setxattr, 2441da177e4SLinus Torvalds .getxattr = generic_getxattr, 2451da177e4SLinus Torvalds .listxattr = ext2_listxattr, 2461da177e4SLinus Torvalds .removexattr = generic_removexattr, 2471da177e4SLinus Torvalds #endif 2481da177e4SLinus Torvalds .setattr = ext2_setattr, 2494e34e719SChristoph Hellwig .get_acl = ext2_get_acl, 25064e178a7SChristoph Hellwig .set_acl = ext2_set_acl, 25168c9d702SJosef Bacik .fiemap = ext2_fiemap, 2521da177e4SLinus Torvalds }; 253