]> git.ipfire.org Git - thirdparty/linux.git/commitdiff
ext2: Remove deprecated DAX support
authorAshwin Gundarapu <linuxuser509@zohomail.in>
Sun, 24 May 2026 15:35:27 +0000 (21:05 +0530)
committerJan Kara <jack@suse.cz>
Mon, 1 Jun 2026 09:20:52 +0000 (11:20 +0200)
DAX support in ext2 was deprecated in commit d5a2693f93e4 ("ext2:
Deprecate DAX") with a removal deadline of end of 2025.  Remove all DAX
code from ext2 as scheduled.

This removes the DAX mount option, IOMAP DAX support, DAX file
operations, DAX address_space_operations, and the DAX fault handler.

[JK: Fixup some whitespace damage]

Signed-off-by: Ashwin Gundarapu <linuxuser509@zohomail.in>
Link: https://patch.msgid.link/19e5aa07c9b.3a2e576d130187.5289857983023045470@zohomail.in
Signed-off-by: Jan Kara <jack@suse.cz>
fs/ext2/ext2.h
fs/ext2/file.c
fs/ext2/inode.c
fs/ext2/super.c

index 3eb1f342645c17aace99be0ba95ce636f354c581..79f7b395258c2ac3d7b2d9a14c468c65beb0e6bb 100644 (file)
@@ -114,8 +114,6 @@ struct ext2_sb_info {
         */
        spinlock_t s_lock;
        struct mb_cache *s_ea_block_cache;
-       struct dax_device *s_daxdev;
-       u64 s_dax_part_off;
 };
 
 static inline spinlock_t *
@@ -373,11 +371,9 @@ struct ext2_inode {
 #define EXT2_MOUNT_NO_UID32            0x000200  /* Disable 32-bit UIDs */
 #define EXT2_MOUNT_XATTR_USER          0x004000  /* Extended user attributes */
 #define EXT2_MOUNT_POSIX_ACL           0x008000  /* POSIX Access Control Lists */
-#define EXT2_MOUNT_XIP                 0x010000  /* Obsolete, use DAX */
 #define EXT2_MOUNT_USRQUOTA            0x020000  /* user quota */
 #define EXT2_MOUNT_GRPQUOTA            0x040000  /* group quota */
 #define EXT2_MOUNT_RESERVATION         0x080000  /* Preallocation */
-#define EXT2_MOUNT_DAX                 0x100000  /* Direct Access */
 
 
 #define clear_opt(o, opt)              o &= ~EXT2_MOUNT_##opt
index d9b1eb34694a044dc9007d8ef924a8ac1d867673..fa0a9750cbd8c998aee5fa1d5a7839df5171d2d6 100644 (file)
@@ -21,7 +21,6 @@
 
 #include <linux/time.h>
 #include <linux/pagemap.h>
-#include <linux/dax.h>
 #include <linux/filelock.h>
 #include <linux/quotaops.h>
 #include <linux/iomap.h>
 #include "acl.h"
 #include "trace.h"
 
-#ifdef CONFIG_FS_DAX
-static ssize_t ext2_dax_read_iter(struct kiocb *iocb, struct iov_iter *to)
-{
-       struct inode *inode = iocb->ki_filp->f_mapping->host;
-       ssize_t ret;
-
-       if (!iov_iter_count(to))
-               return 0; /* skip atime */
-
-       inode_lock_shared(inode);
-       ret = dax_iomap_rw(iocb, to, &ext2_iomap_ops);
-       inode_unlock_shared(inode);
-
-       file_accessed(iocb->ki_filp);
-       return ret;
-}
-
-static ssize_t ext2_dax_write_iter(struct kiocb *iocb, struct iov_iter *from)
-{
-       struct file *file = iocb->ki_filp;
-       struct inode *inode = file->f_mapping->host;
-       ssize_t ret;
-
-       inode_lock(inode);
-       ret = generic_write_checks(iocb, from);
-       if (ret <= 0)
-               goto out_unlock;
-       ret = file_remove_privs(file);
-       if (ret)
-               goto out_unlock;
-       ret = file_update_time(file);
-       if (ret)
-               goto out_unlock;
-
-       ret = dax_iomap_rw(iocb, from, &ext2_iomap_ops);
-       if (ret > 0 && iocb->ki_pos > i_size_read(inode)) {
-               i_size_write(inode, iocb->ki_pos);
-               mark_inode_dirty(inode);
-       }
-
-out_unlock:
-       inode_unlock(inode);
-       if (ret > 0)
-               ret = generic_write_sync(iocb, ret);
-       return ret;
-}
-
-/*
- * The lock ordering for ext2 DAX fault paths is:
- *
- * mmap_lock (MM)
- *   sb_start_pagefault (vfs, freeze)
- *     address_space->invalidate_lock
- *       address_space->i_mmap_rwsem or page_lock (mutually exclusive in DAX)
- *         ext2_inode_info->truncate_mutex
- *
- * The default page_lock and i_size verification done by non-DAX fault paths
- * is sufficient because ext2 doesn't support hole punching.
- */
-static vm_fault_t ext2_dax_fault(struct vm_fault *vmf)
-{
-       struct inode *inode = file_inode(vmf->vma->vm_file);
-       vm_fault_t ret;
-       bool write = (vmf->flags & FAULT_FLAG_WRITE) &&
-               (vmf->vma->vm_flags & VM_SHARED);
-
-       if (write) {
-               sb_start_pagefault(inode->i_sb);
-               file_update_time(vmf->vma->vm_file);
-       }
-       filemap_invalidate_lock_shared(inode->i_mapping);
-
-       ret = dax_iomap_fault(vmf, 0, NULL, NULL, &ext2_iomap_ops);
-
-       filemap_invalidate_unlock_shared(inode->i_mapping);
-       if (write)
-               sb_end_pagefault(inode->i_sb);
-       return ret;
-}
-
-static const struct vm_operations_struct ext2_dax_vm_ops = {
-       .fault          = ext2_dax_fault,
-       /*
-        * .huge_fault is not supported for DAX because allocation in ext2
-        * cannot be reliably aligned to huge page sizes and so pmd faults
-        * will always fail and fail back to regular faults.
-        */
-       .page_mkwrite   = ext2_dax_fault,
-       .pfn_mkwrite    = ext2_dax_fault,
-};
-
-static int ext2_file_mmap_prepare(struct vm_area_desc *desc)
-{
-       struct file *file = desc->file;
-
-       if (!IS_DAX(file_inode(file)))
-               return generic_file_mmap_prepare(desc);
-
-       file_accessed(file);
-       desc->vm_ops = &ext2_dax_vm_ops;
-       return 0;
-}
-#else
-#define ext2_file_mmap_prepare generic_file_mmap_prepare
-#endif
 
 /*
  * Called when filp is released. This happens when all file descriptors
@@ -285,10 +179,6 @@ out_unlock:
 
 static ssize_t ext2_file_read_iter(struct kiocb *iocb, struct iov_iter *to)
 {
-#ifdef CONFIG_FS_DAX
-       if (IS_DAX(iocb->ki_filp->f_mapping->host))
-               return ext2_dax_read_iter(iocb, to);
-#endif
        if (iocb->ki_flags & IOCB_DIRECT)
                return ext2_dio_read_iter(iocb, to);
 
@@ -297,10 +187,6 @@ static ssize_t ext2_file_read_iter(struct kiocb *iocb, struct iov_iter *to)
 
 static ssize_t ext2_file_write_iter(struct kiocb *iocb, struct iov_iter *from)
 {
-#ifdef CONFIG_FS_DAX
-       if (IS_DAX(iocb->ki_filp->f_mapping->host))
-               return ext2_dax_write_iter(iocb, from);
-#endif
        if (iocb->ki_flags & IOCB_DIRECT)
                return ext2_dio_write_iter(iocb, from);
 
@@ -321,7 +207,7 @@ const struct file_operations ext2_file_operations = {
 #ifdef CONFIG_COMPAT
        .compat_ioctl   = ext2_compat_ioctl,
 #endif
-       .mmap_prepare   = ext2_file_mmap_prepare,
+       .mmap_prepare   = generic_file_mmap_prepare,
        .open           = ext2_file_open,
        .release        = ext2_release_file,
        .fsync          = ext2_fsync,
index 74aca5eb572d96ef33263fcf8cf1943a5ad15d88..29808629cce56fd4958e56d962eb1dc2536bd743 100644 (file)
@@ -26,7 +26,6 @@
 #include <linux/time.h>
 #include <linux/highuid.h>
 #include <linux/pagemap.h>
-#include <linux/dax.h>
 #include <linux/blkdev.h>
 #include <linux/quotaops.h>
 #include <linux/writeback.h>
@@ -741,27 +740,6 @@ static int ext2_get_blocks(struct inode *inode,
                goto cleanup;
        }
 
-       if (IS_DAX(inode)) {
-               /*
-                * We must unmap blocks before zeroing so that writeback cannot
-                * overwrite zeros with stale data from block device page cache.
-                */
-               clean_bdev_aliases(inode->i_sb->s_bdev,
-                                  le32_to_cpu(chain[depth-1].key),
-                                  count);
-               /*
-                * block must be initialised before we put it in the tree
-                * so that it's not found by another thread before it's
-                * initialised
-                */
-               err = sb_issue_zeroout(inode->i_sb,
-                               le32_to_cpu(chain[depth-1].key), count,
-                               GFP_KERNEL);
-               if (err) {
-                       mutex_unlock(&ei->truncate_mutex);
-                       goto cleanup;
-               }
-       }
        *new = true;
 
        ext2_splice_branch(inode, iblock, partial, indirect_blks, count);
@@ -811,7 +789,6 @@ static int ext2_iomap_begin(struct inode *inode, loff_t offset, loff_t length,
        unsigned int blkbits = inode->i_blkbits;
        unsigned long first_block = offset >> blkbits;
        unsigned long max_blocks = (length + (1 << blkbits) - 1) >> blkbits;
-       struct ext2_sb_info *sbi = EXT2_SB(inode->i_sb);
        bool new = false, boundary = false;
        u32 bno;
        int ret;
@@ -841,10 +818,7 @@ static int ext2_iomap_begin(struct inode *inode, loff_t offset, loff_t length,
 
        iomap->flags = 0;
        iomap->offset = (u64)first_block << blkbits;
-       if (flags & IOMAP_DAX)
-               iomap->dax_dev = sbi->s_daxdev;
-       else
-               iomap->bdev = inode->i_sb->s_bdev;
+       iomap->bdev = inode->i_sb->s_bdev;
 
        if (ret == 0) {
                /*
@@ -859,8 +833,6 @@ static int ext2_iomap_begin(struct inode *inode, loff_t offset, loff_t length,
        } else {
                iomap->type = IOMAP_MAPPED;
                iomap->addr = (u64)bno << blkbits;
-               if (flags & IOMAP_DAX)
-                       iomap->addr += sbi->s_dax_part_off;
                iomap->length = (u64)ret << blkbits;
                iomap->flags |= IOMAP_F_MERGED;
        }
@@ -962,13 +934,6 @@ ext2_writepages(struct address_space *mapping, struct writeback_control *wbc)
        return mpage_writepages(mapping, wbc, ext2_get_block);
 }
 
-static int
-ext2_dax_writepages(struct address_space *mapping, struct writeback_control *wbc)
-{
-       struct ext2_sb_info *sbi = EXT2_SB(mapping->host->i_sb);
-
-       return dax_writeback_mapping_range(mapping, sbi->s_daxdev, wbc);
-}
 
 const struct address_space_operations ext2_aops = {
        .dirty_folio            = block_dirty_folio,
@@ -984,10 +949,6 @@ const struct address_space_operations ext2_aops = {
        .error_remove_folio     = generic_error_remove_folio,
 };
 
-static const struct address_space_operations ext2_dax_aops = {
-       .writepages             = ext2_dax_writepages,
-       .dirty_folio            = noop_dirty_folio,
-};
 
 /*
  * Probably it should be a library function... search for first non-zero word
@@ -1186,9 +1147,6 @@ static void __ext2_truncate_blocks(struct inode *inode, loff_t offset)
        blocksize = inode->i_sb->s_blocksize;
        iblock = (offset + blocksize-1) >> EXT2_BLOCK_SIZE_BITS(inode->i_sb);
 
-#ifdef CONFIG_FS_DAX
-       WARN_ON(!rwsem_is_locked(&inode->i_mapping->invalidate_lock));
-#endif
 
        n = ext2_block_to_path(inode, iblock, offsets, NULL);
        if (n == 0)
@@ -1290,12 +1248,7 @@ static int ext2_setsize(struct inode *inode, loff_t newsize)
 
        inode_dio_wait(inode);
 
-       if (IS_DAX(inode))
-               error = dax_truncate_page(inode, newsize, NULL,
-                                         &ext2_iomap_ops);
-       else
-               error = block_truncate_page(inode->i_mapping,
-                               newsize, ext2_get_block);
+       error = block_truncate_page(inode->i_mapping, newsize, ext2_get_block);
        if (error)
                return error;
 
@@ -1363,7 +1316,7 @@ void ext2_set_inode_flags(struct inode *inode)
        unsigned int flags = EXT2_I(inode)->i_flags;
 
        inode->i_flags &= ~(S_SYNC | S_APPEND | S_IMMUTABLE | S_NOATIME |
-                               S_DIRSYNC | S_DAX);
+                               S_DIRSYNC);
        if (flags & EXT2_SYNC_FL)
                inode->i_flags |= S_SYNC;
        if (flags & EXT2_APPEND_FL)
@@ -1374,18 +1327,13 @@ void ext2_set_inode_flags(struct inode *inode)
                inode->i_flags |= S_NOATIME;
        if (flags & EXT2_DIRSYNC_FL)
                inode->i_flags |= S_DIRSYNC;
-       if (test_opt(inode->i_sb, DAX) && S_ISREG(inode->i_mode))
-               inode->i_flags |= S_DAX;
 }
 
 void ext2_set_file_ops(struct inode *inode)
 {
        inode->i_op = &ext2_file_inode_operations;
        inode->i_fop = &ext2_file_operations;
-       if (IS_DAX(inode))
-               inode->i_mapping->a_ops = &ext2_dax_aops;
-       else
-               inode->i_mapping->a_ops = &ext2_aops;
+       inode->i_mapping->a_ops = &ext2_aops;
 }
 
 struct inode *ext2_iget (struct super_block *sb, unsigned long ino)
index 19f76d8cb47344004f7af7b53c1826a681a42e31..3999f8f3b156e345811e211e8e0372931a825d55 100644 (file)
@@ -34,7 +34,6 @@
 #include <linux/log2.h>
 #include <linux/quotaops.h>
 #include <linux/uaccess.h>
-#include <linux/dax.h>
 #include <linux/iversion.h>
 #include "ext2.h"
 #include "xattr.h"
@@ -198,7 +197,6 @@ static void ext2_put_super (struct super_block * sb)
        brelse (sbi->s_sbh);
        sb->s_fs_info = NULL;
        kfree(sbi->s_blockgroup_lock);
-       fs_put_dax(sbi->s_daxdev, NULL);
        kfree(sbi);
 }
 
@@ -329,11 +327,7 @@ static int ext2_show_options(struct seq_file *seq, struct dentry *root)
        if (test_opt(sb, GRPQUOTA))
                seq_puts(seq, ",grpquota");
 
-       if (test_opt(sb, XIP))
-               seq_puts(seq, ",xip");
 
-       if (test_opt(sb, DAX))
-               seq_puts(seq, ",dax");
 
        if (!test_opt(sb, RESERVATION))
                seq_puts(seq, ",noreservation");
@@ -596,18 +590,10 @@ static int ext2_parse_param(struct fs_context *fc, struct fs_parameter *param)
                break;
 #endif
        case Opt_xip:
-               ext2_msg_fc(fc, KERN_INFO, "use dax instead of xip");
-               ctx_set_mount_opt(ctx, EXT2_MOUNT_XIP);
-               fallthrough;
+               ext2_msg_fc(fc, KERN_WARNING, "DAX support has been removed. xip option ignored.");
+               break;
        case Opt_dax:
-#ifdef CONFIG_FS_DAX
-               ext2_msg_fc(fc, KERN_WARNING,
-                   "DAX enabled. Warning: DAX support in ext2 driver is deprecated"
-                   " and will be removed at the end of 2025. Please use ext4 driver instead.");
-               ctx_set_mount_opt(ctx, EXT2_MOUNT_DAX);
-#else
-               ext2_msg_fc(fc, KERN_INFO, "dax option not supported");
-#endif
+               ext2_msg_fc(fc, KERN_WARNING, "DAX support has been removed. dax option ignored.");
                break;
 
 #if defined(CONFIG_QUOTA)
@@ -906,8 +892,6 @@ static int ext2_fill_super(struct super_block *sb, struct fs_context *fc)
        }
        sb->s_fs_info = sbi;
        sbi->s_sb_block = sb_block;
-       sbi->s_daxdev = fs_dax_get_by_bdev(sb->s_bdev, &sbi->s_dax_part_off,
-                                          NULL, NULL);
 
        spin_lock_init(&sbi->s_lock);
        ret = -EINVAL;
@@ -992,17 +976,6 @@ static int ext2_fill_super(struct super_block *sb, struct fs_context *fc)
        }
        blocksize = BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size);
 
-       if (test_opt(sb, DAX)) {
-               if (!sbi->s_daxdev) {
-                       ext2_msg(sb, KERN_ERR,
-                               "DAX unsupported by block device. Turning off DAX.");
-                       clear_opt(sbi->s_mount_opt, DAX);
-               } else if (blocksize != PAGE_SIZE) {
-                       ext2_msg(sb, KERN_ERR, "unsupported blocksize for DAX\n");
-                       clear_opt(sbi->s_mount_opt, DAX);
-               }
-       }
-
        /* If the blocksize doesn't match, re-read the thing.. */
        if (sb->s_blocksize != blocksize) {
                brelse(bh);
@@ -1252,7 +1225,6 @@ failed_mount_group_desc:
 failed_mount:
        brelse(bh);
 failed_sbi:
-       fs_put_dax(sbi->s_daxdev, NULL);
        sb->s_fs_info = NULL;
        kfree(sbi->s_blockgroup_lock);
        kfree(sbi);
@@ -1379,11 +1351,6 @@ static int ext2_reconfigure(struct fs_context *fc)
 
        spin_lock(&sbi->s_lock);
        es = sbi->s_es;
-       if ((sbi->s_mount_opt ^ new_opts.s_mount_opt) & EXT2_MOUNT_DAX) {
-               ext2_msg(sb, KERN_WARNING, "warning: refusing change of "
-                        "dax flag with busy inodes while remounting");
-               new_opts.s_mount_opt ^= EXT2_MOUNT_DAX;
-       }
        if ((bool)(flags & SB_RDONLY) == sb_rdonly(sb))
                goto out_set;
        if (flags & SB_RDONLY) {