| Message ID | 20210924130959.2695749-8-ruansy.fnst@fujitsu.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | fsdax: introduce fs query to support reflink | expand |
On Fri, Sep 24, 2021 at 09:09:58PM +0800, Shiyang Ruan wrote: > This function is used to handle errors which may cause data lost in > filesystem. Such as memory failure in fsdax mode. > > If the rmap feature of XFS enabled, we can query it to find files and > metadata which are associated with the corrupt data. For now all we do > is kill processes with that file mapped into their address spaces, but > future patches could actually do something about corrupt metadata. > > After that, the memory failure needs to notify the processes who are > using those files. > > Signed-off-by: Shiyang Ruan <ruansy.fnst@fujitsu.com> > --- > drivers/dax/super.c | 19 +++++ > fs/xfs/xfs_fsops.c | 3 + > fs/xfs/xfs_mount.h | 1 + > fs/xfs/xfs_super.c | 188 ++++++++++++++++++++++++++++++++++++++++++++ > include/linux/dax.h | 18 +++++ > 5 files changed, 229 insertions(+) > > diff --git a/drivers/dax/super.c b/drivers/dax/super.c > index 7d4a11dcba90..22091e7fb0ef 100644 > --- a/drivers/dax/super.c > +++ b/drivers/dax/super.c > @@ -135,6 +135,25 @@ struct dax_device *fs_dax_get_by_bdev(struct block_device *bdev) > } > EXPORT_SYMBOL_GPL(fs_dax_get_by_bdev); > > +void fs_dax_register_holder(struct dax_device *dax_dev, void *holder, > + const struct dax_holder_operations *ops) > +{ > + dax_set_holder(dax_dev, holder, ops); > +} > +EXPORT_SYMBOL_GPL(fs_dax_register_holder); > + > +void fs_dax_unregister_holder(struct dax_device *dax_dev) > +{ > + dax_set_holder(dax_dev, NULL, NULL); > +} > +EXPORT_SYMBOL_GPL(fs_dax_unregister_holder); > + > +void *fs_dax_get_holder(struct dax_device *dax_dev) > +{ > + return dax_get_holder(dax_dev); > +} > +EXPORT_SYMBOL_GPL(fs_dax_get_holder); > + > bool generic_fsdax_supported(struct dax_device *dax_dev, > struct block_device *bdev, int blocksize, sector_t start, > sector_t sectors) > diff --git a/fs/xfs/xfs_fsops.c b/fs/xfs/xfs_fsops.c > index 33e26690a8c4..4c2d3d4ca5a5 100644 > --- a/fs/xfs/xfs_fsops.c > +++ b/fs/xfs/xfs_fsops.c > @@ -542,6 +542,9 @@ xfs_do_force_shutdown( > } else if (flags & SHUTDOWN_CORRUPT_INCORE) { > tag = XFS_PTAG_SHUTDOWN_CORRUPT; > why = "Corruption of in-memory data"; > + } else if (flags & SHUTDOWN_CORRUPT_META) { > + tag = XFS_PTAG_SHUTDOWN_CORRUPT; > + why = "Corruption of on-disk metadata"; > } else { > tag = XFS_PTAG_SHUTDOWN_IOERROR; > why = "Metadata I/O Error"; > diff --git a/fs/xfs/xfs_mount.h b/fs/xfs/xfs_mount.h > index e091f3b3fa15..d0f6da23e3df 100644 > --- a/fs/xfs/xfs_mount.h > +++ b/fs/xfs/xfs_mount.h > @@ -434,6 +434,7 @@ void xfs_do_force_shutdown(struct xfs_mount *mp, int lags, char *fname, > #define SHUTDOWN_LOG_IO_ERROR 0x0002 /* write attempt to the log failed */ > #define SHUTDOWN_FORCE_UMOUNT 0x0004 /* shutdown from a forced unmount */ > #define SHUTDOWN_CORRUPT_INCORE 0x0008 /* corrupt in-memory data structures */ > +#define SHUTDOWN_CORRUPT_META 0x0010 /* corrupt metadata on device */ > > #define XFS_SHUTDOWN_STRINGS \ > { SHUTDOWN_META_IO_ERROR, "metadata_io" }, \ > diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c > index c4e0cd1c1c8c..46fdf44b5ec2 100644 > --- a/fs/xfs/xfs_super.c > +++ b/fs/xfs/xfs_super.c > @@ -37,11 +37,19 @@ > #include "xfs_reflink.h" > #include "xfs_pwork.h" > #include "xfs_ag.h" > +#include "xfs_alloc.h" > +#include "xfs_rmap.h" > +#include "xfs_rmap_btree.h" > +#include "xfs_rtalloc.h" > +#include "xfs_bit.h" > > #include <linux/magic.h> > #include <linux/fs_context.h> > #include <linux/fs_parser.h> > +#include <linux/mm.h> > +#include <linux/dax.h> > > +static const struct dax_holder_operations xfs_dax_holder_operations; > static const struct super_operations xfs_super_operations; > > static struct kset *xfs_kset; /* top-level xfs sysfs dir */ > @@ -377,6 +385,8 @@ xfs_close_devices( > > xfs_free_buftarg(mp->m_logdev_targp); > xfs_blkdev_put(logdev); > + if (dax_logdev) > + fs_dax_unregister_holder(dax_logdev); > fs_put_dax(dax_logdev); > } > if (mp->m_rtdev_targp) { > @@ -385,9 +395,13 @@ xfs_close_devices( > > xfs_free_buftarg(mp->m_rtdev_targp); > xfs_blkdev_put(rtdev); > + if (dax_rtdev) > + fs_dax_unregister_holder(dax_rtdev); > fs_put_dax(dax_rtdev); > } > xfs_free_buftarg(mp->m_ddev_targp); > + if (dax_ddev) > + fs_dax_unregister_holder(dax_ddev); > fs_put_dax(dax_ddev); > } > > @@ -411,6 +425,9 @@ xfs_open_devices( > struct block_device *logdev = NULL, *rtdev = NULL; > int error; > > + if (dax_ddev) > + fs_dax_register_holder(dax_ddev, mp, > + &xfs_dax_holder_operations); > /* > * Open real time and log devices - order is important. > */ > @@ -419,6 +436,9 @@ xfs_open_devices( > if (error) > goto out; > dax_logdev = fs_dax_get_by_bdev(logdev); > + if (dax_logdev != dax_ddev && dax_logdev) > + fs_dax_register_holder(dax_logdev, mp, > + &xfs_dax_holder_operations); > } > > if (mp->m_rtname) { > @@ -433,6 +453,9 @@ xfs_open_devices( > goto out_close_rtdev; > } > dax_rtdev = fs_dax_get_by_bdev(rtdev); > + if (dax_rtdev) > + fs_dax_register_holder(dax_rtdev, mp, > + &xfs_dax_holder_operations); > } > > /* > @@ -1110,6 +1133,171 @@ xfs_fs_free_cached_objects( > return xfs_reclaim_inodes_nr(XFS_M(sb), sc->nr_to_scan); > } > > +struct notify_failure_info { > + xfs_agblock_t startblock; Style nit: tabs between type name and variable name. > + xfs_filblks_t blockcount; > + int flags; Are these MF_ flags to be passed from memory_failure to mf_dax_kill_procs? > +}; > + > +static loff_t > +xfs_notify_failure_start( > + struct xfs_mount *mp, > + const struct xfs_rmap_irec *rec, > + const struct notify_failure_info *notify) > +{ > + loff_t start = rec->rm_offset; > + > + if (notify->startblock > rec->rm_startblock) > + start += XFS_FSB_TO_B(mp, > + notify->startblock - rec->rm_startblock); I'm confused, is this supposed to return the file pos(ition) of the failed range in units of bytes or in fs blocks? If it's units of bytes (like the loff_t return value implies) then this should be called xfs_notify_failure_pos. > + return start; > +} > + > +static size_t > +xfs_notify_failure_size( > + struct xfs_mount *mp, > + const struct xfs_rmap_irec *rec, > + const struct notify_failure_info *notify) > +{ > + xfs_agblock_t rec_start = rec->rm_startblock; > + xfs_agblock_t rec_end = rec->rm_startblock + rec->rm_blockcount; These are "next" variables, not "end". The end of the record is startblock + blockcount - 1. > + xfs_agblock_t notify_start = notify->startblock; > + xfs_agblock_t notify_end = notify->startblock + notify->blockcount; > + xfs_agblock_t cross_start = max(rec_start, notify_start); > + xfs_agblock_t cross_end = min(rec_end, notify_end); > + > + return XFS_FSB_TO_B(mp, cross_end - cross_start); > +} > + > +static int > +xfs_dax_notify_failure_fn( > + struct xfs_btree_cur *cur, > + const struct xfs_rmap_irec *rec, > + void *data) > +{ > + struct xfs_mount *mp = cur->bc_mp; > + struct xfs_inode *ip; > + struct address_space *mapping; > + struct notify_failure_info *notify = data; > + int error = 0; > + > + if (XFS_RMAP_NON_INODE_OWNER(rec->rm_owner) || > + (rec->rm_flags & (XFS_RMAP_ATTR_FORK | XFS_RMAP_BMBT_BLOCK))) { > + // TODO check and try to fix metadata > + xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_META); > + return -EFSCORRUPTED; > + } > + > + /* Get files that incore, filter out others that are not in use. */ > + error = xfs_iget(mp, cur->bc_tp, rec->rm_owner, XFS_IGET_INCORE, > + 0, &ip); If you're going to use _INCORE then you probably want to filter out the -ENODATA or whatever error code means "inode wasn't loaded", because returning any nonzero value to rmap_query_range causes it to stop iterating. > + if (error) > + return error; > + > + mapping = VFS_I(ip)->i_mapping; > + if (IS_ENABLED(CONFIG_MEMORY_FAILURE)) { > + loff_t offset = xfs_notify_failure_start(mp, rec, notify); > + size_t size = xfs_notify_failure_size(mp, rec, notify); > + > + error = mf_dax_kill_procs(mapping, offset >> PAGE_SHIFT, size, > + notify->flags); > + } > + // TODO try to fix data > + xfs_irele(ip); > + > + return error; > +} > + > +static loff_t > +xfs_dax_bdev_offset( > + struct xfs_mount *mp, > + struct dax_device *dax_dev, > + loff_t disk_offset) > +{ > + struct block_device *bdev; > + > + if (mp->m_ddev_targp->bt_daxdev == dax_dev) > + bdev = mp->m_ddev_targp->bt_bdev; > + else if (mp->m_logdev_targp->bt_daxdev == dax_dev) > + bdev = mp->m_logdev_targp->bt_bdev; > + else > + bdev = mp->m_rtdev_targp->bt_bdev; > + > + return disk_offset - (get_start_sect(bdev) << SECTOR_SHIFT); > +} > + > +static int > +xfs_dax_notify_failure( > + struct dax_device *dax_dev, > + loff_t offset, > + size_t len, > + int flags) Are @flags supposed to contain the MF_ flags that were passed to memory_failure()? The variable name should probably be @mf_flags throughout the patchset if that's the case. > +{ > + struct xfs_mount *mp = fs_dax_get_holder(dax_dev); > + struct xfs_trans *tp = NULL; > + struct xfs_btree_cur *cur = NULL; > + struct xfs_buf *agf_bp = NULL; > + struct xfs_rmap_irec rmap_low, rmap_high; > + loff_t bdev_offset = xfs_dax_bdev_offset(mp, dax_dev, > + offset); I don't like using loff_t to represent byte offsets into the physical device. loff_t should be used only for file byte offsets, and that's not what we're storing here. > + xfs_fsblock_t fsbno = XFS_B_TO_FSB(mp, bdev_offset); I think this is still wrong, since fsblocks are segmented (nonlinear) addresses. Pass daddr into xfs_dax_notify_ddev_failure like I lay out below, and then you can do: start_fsbno = XFS_DADDR_TO_FSB(mp, daddr); agno = XFS_FSB_TO_AGNO(mp, fsbno); notify.startblock = XFS_FSB_TO_AGBNO(mp, fsbno); notify.blockcount = XFS_BB_TO_FSB(mp, bblen); (More on this below) > + xfs_agnumber_t agno = XFS_FSB_TO_AGNO(mp, fsbno); > + int error = 0; > + struct notify_failure_info notify = { > + .startblock = XFS_FSB_TO_AGBNO(mp, fsbno), > + .blockcount = XFS_B_TO_FSB(mp, len), > + .flags = flags, > + }; > + > + if (mp->m_rtdev_targp && mp->m_rtdev_targp->bt_daxdev == dax_dev) { > + xfs_warn(mp, > + "notify_failure() not supported on realtime device!"); > + return -EOPNOTSUPP; > + } > + > + if (mp->m_logdev_targp && mp->m_logdev_targp->bt_daxdev == dax_dev && > + mp->m_logdev_targp != mp->m_ddev_targp) { > + xfs_err(mp, "ondisk log corrupt, shutting down fs!"); > + xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_META); > + return -EFSCORRUPTED; > + } Urk. xfs_dax_notify_failure should be a short function to dispatch the notification to the proper handler. Everything from here down should be in a separate function xfs_dax_notify_ddev_failure, so that the next line of xfs_dax_notify_failure is just: return xfs_dax_notify_ddev_failure(mp, BTOBB(offset), BTOBB(len), flags); And then we have static int xfs_dax_notify_ddev_failure( struct xfs_mount *mp, xfs_daddr_t daddr, xfs_daddr_t bblen, int mf_flags) { if (!xfs_has_rmapbt(mp)) { xfs_warn(...); Because otherwise xfs_dax_notify_failure gets cluttered. > + > + if (!xfs_has_rmapbt(mp)) { > + xfs_warn(mp, "notify_failure() needs rmapbt enabled!"); > + return -EOPNOTSUPP; > + } > + > + error = xfs_trans_alloc_empty(mp, &tp); > + if (error) > + return error; > + > + error = xfs_alloc_read_agf(mp, tp, agno, 0, &agf_bp); > + if (error) > + goto out_cancel_tp; > + > + cur = xfs_rmapbt_init_cursor(mp, tp, agf_bp, agf_bp->b_pag); What happens if the failure range spans multiple AGs? I suppose it's not technically possible today since we only report a single page at a time. But for the general case, I think we actually want (building off the sample code above) this function to do something like this: start_fsbno = XFS_DADDR_TO_FSB(mp, daddr); agno = XFS_FSB_TO_AGNO(mp, fsbno); end_fsbno = XFS_DADDR_TO_FSB(mp, daddr + bblen); end_agno = XFS_FSB_TO_AGNO(mp, end_fsbno); for (; agno <= end_agbno; agno++) { struct xfs_rmap_irec rmap_low = { }; struct xfs_rmap_irec rmap_high; notify.startblock = XFS_FSB_TO_AGBNO(mp, fsbno); notify.blockcount = XFS_BB_TO_FSB(mp, bblen); /* * init transaction, read agf, init cursor... */ memset(&rmap_high, 0xFF, sizeof(rmap_high)); rmap_low.rm_startblock = XFS_FSB_TO_AGBNO(mp, fsbno); if (agno == end_agbno) rmap_high.rm_startblock = XFS_FSB_TO_AGBNO(mp, end_fsbno); error = xfs_rmap_query_range(...); if (error) fail; fsbno = XFS_AGB_TO_FSB(mp, agno + 1, 0); } --D > + > + /* Construct a range for rmap query */ > + memset(&rmap_low, 0, sizeof(rmap_low)); > + memset(&rmap_high, 0xFF, sizeof(rmap_high)); > + rmap_low.rm_startblock = rmap_high.rm_startblock = notify.startblock; > + rmap_low.rm_blockcount = rmap_high.rm_blockcount = notify.blockcount; > + > + error = xfs_rmap_query_range(cur, &rmap_low, &rmap_high, > + xfs_dax_notify_failure_fn, ¬ify); > + > + xfs_btree_del_cursor(cur, error); > + xfs_trans_brelse(tp, agf_bp); > + > +out_cancel_tp: > + xfs_trans_cancel(tp); > + return error; > +} > + > +static const struct dax_holder_operations xfs_dax_holder_operations = { > + .notify_failure = xfs_dax_notify_failure, > +}; > + > static const struct super_operations xfs_super_operations = { > .alloc_inode = xfs_fs_alloc_inode, > .destroy_inode = xfs_fs_destroy_inode, > diff --git a/include/linux/dax.h b/include/linux/dax.h > index 3d90becbd160..0f1fa7a4a616 100644 > --- a/include/linux/dax.h > +++ b/include/linux/dax.h > @@ -149,6 +149,10 @@ static inline void fs_put_dax(struct dax_device *dax_dev) > } > > struct dax_device *fs_dax_get_by_bdev(struct block_device *bdev); > +void fs_dax_register_holder(struct dax_device *dax_dev, void *holder, > + const struct dax_holder_operations *ops); > +void fs_dax_unregister_holder(struct dax_device *dax_dev); > +void *fs_dax_get_holder(struct dax_device *dax_dev); > int dax_writeback_mapping_range(struct address_space *mapping, > struct dax_device *dax_dev, struct writeback_control *wbc); > > @@ -179,6 +183,20 @@ static inline struct dax_device *fs_dax_get_by_bdev(struct block_device *bdev) > return NULL; > } > > +static inline void fs_dax_register_holder(struct dax_device *dax_dev, > + void *holder, const struct dax_holder_operations *ops) > +{ > +} > + > +static inline void fs_dax_unregister_holder(struct dax_device *dax_dev) > +{ > +} > + > +static inline void *fs_dax_get_holder(struct dax_device *dax_dev) > +{ > + return NULL; > +} > + > static inline struct page *dax_layout_busy_page(struct address_space *mapping) > { > return NULL; > -- > 2.33.0 > > >
On Fri, Sep 24, 2021 at 09:09:58PM +0800, Shiyang Ruan wrote: > +void fs_dax_register_holder(struct dax_device *dax_dev, void *holder, > + const struct dax_holder_operations *ops) > +{ > + dax_set_holder(dax_dev, holder, ops); > +} > +EXPORT_SYMBOL_GPL(fs_dax_register_holder); > + > +void fs_dax_unregister_holder(struct dax_device *dax_dev) > +{ > + dax_set_holder(dax_dev, NULL, NULL); > +} > +EXPORT_SYMBOL_GPL(fs_dax_unregister_holder); > + > +void *fs_dax_get_holder(struct dax_device *dax_dev) > +{ > + return dax_get_holder(dax_dev); > +} > +EXPORT_SYMBOL_GPL(fs_dax_get_holder); These should not be in a XFS patch. But why do we even need this wrappers? > @@ -377,6 +385,8 @@ xfs_close_devices( > > xfs_free_buftarg(mp->m_logdev_targp); > xfs_blkdev_put(logdev); > + if (dax_logdev) > + fs_dax_unregister_holder(dax_logdev); > fs_put_dax(dax_logdev); I'd prefer to include the fs_dax_unregister_holder in the fs_put_dax call to avoid callers failing to unregister it. > @@ -411,6 +425,9 @@ xfs_open_devices( > struct block_device *logdev = NULL, *rtdev = NULL; > int error; > > + if (dax_ddev) > + fs_dax_register_holder(dax_ddev, mp, > + &xfs_dax_holder_operations); I'd include the holder registration with fs_dax_get_by_bdev as well.
diff --git a/drivers/dax/super.c b/drivers/dax/super.c index 7d4a11dcba90..22091e7fb0ef 100644 --- a/drivers/dax/super.c +++ b/drivers/dax/super.c @@ -135,6 +135,25 @@ struct dax_device *fs_dax_get_by_bdev(struct block_device *bdev) } EXPORT_SYMBOL_GPL(fs_dax_get_by_bdev); +void fs_dax_register_holder(struct dax_device *dax_dev, void *holder, + const struct dax_holder_operations *ops) +{ + dax_set_holder(dax_dev, holder, ops); +} +EXPORT_SYMBOL_GPL(fs_dax_register_holder); + +void fs_dax_unregister_holder(struct dax_device *dax_dev) +{ + dax_set_holder(dax_dev, NULL, NULL); +} +EXPORT_SYMBOL_GPL(fs_dax_unregister_holder); + +void *fs_dax_get_holder(struct dax_device *dax_dev) +{ + return dax_get_holder(dax_dev); +} +EXPORT_SYMBOL_GPL(fs_dax_get_holder); + bool generic_fsdax_supported(struct dax_device *dax_dev, struct block_device *bdev, int blocksize, sector_t start, sector_t sectors) diff --git a/fs/xfs/xfs_fsops.c b/fs/xfs/xfs_fsops.c index 33e26690a8c4..4c2d3d4ca5a5 100644 --- a/fs/xfs/xfs_fsops.c +++ b/fs/xfs/xfs_fsops.c @@ -542,6 +542,9 @@ xfs_do_force_shutdown( } else if (flags & SHUTDOWN_CORRUPT_INCORE) { tag = XFS_PTAG_SHUTDOWN_CORRUPT; why = "Corruption of in-memory data"; + } else if (flags & SHUTDOWN_CORRUPT_META) { + tag = XFS_PTAG_SHUTDOWN_CORRUPT; + why = "Corruption of on-disk metadata"; } else { tag = XFS_PTAG_SHUTDOWN_IOERROR; why = "Metadata I/O Error"; diff --git a/fs/xfs/xfs_mount.h b/fs/xfs/xfs_mount.h index e091f3b3fa15..d0f6da23e3df 100644 --- a/fs/xfs/xfs_mount.h +++ b/fs/xfs/xfs_mount.h @@ -434,6 +434,7 @@ void xfs_do_force_shutdown(struct xfs_mount *mp, int flags, char *fname, #define SHUTDOWN_LOG_IO_ERROR 0x0002 /* write attempt to the log failed */ #define SHUTDOWN_FORCE_UMOUNT 0x0004 /* shutdown from a forced unmount */ #define SHUTDOWN_CORRUPT_INCORE 0x0008 /* corrupt in-memory data structures */ +#define SHUTDOWN_CORRUPT_META 0x0010 /* corrupt metadata on device */ #define XFS_SHUTDOWN_STRINGS \ { SHUTDOWN_META_IO_ERROR, "metadata_io" }, \ diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c index c4e0cd1c1c8c..46fdf44b5ec2 100644 --- a/fs/xfs/xfs_super.c +++ b/fs/xfs/xfs_super.c @@ -37,11 +37,19 @@ #include "xfs_reflink.h" #include "xfs_pwork.h" #include "xfs_ag.h" +#include "xfs_alloc.h" +#include "xfs_rmap.h" +#include "xfs_rmap_btree.h" +#include "xfs_rtalloc.h" +#include "xfs_bit.h" #include <linux/magic.h> #include <linux/fs_context.h> #include <linux/fs_parser.h> +#include <linux/mm.h> +#include <linux/dax.h> +static const struct dax_holder_operations xfs_dax_holder_operations; static const struct super_operations xfs_super_operations; static struct kset *xfs_kset; /* top-level xfs sysfs dir */ @@ -377,6 +385,8 @@ xfs_close_devices( xfs_free_buftarg(mp->m_logdev_targp); xfs_blkdev_put(logdev); + if (dax_logdev) + fs_dax_unregister_holder(dax_logdev); fs_put_dax(dax_logdev); } if (mp->m_rtdev_targp) { @@ -385,9 +395,13 @@ xfs_close_devices( xfs_free_buftarg(mp->m_rtdev_targp); xfs_blkdev_put(rtdev); + if (dax_rtdev) + fs_dax_unregister_holder(dax_rtdev); fs_put_dax(dax_rtdev); } xfs_free_buftarg(mp->m_ddev_targp); + if (dax_ddev) + fs_dax_unregister_holder(dax_ddev); fs_put_dax(dax_ddev); } @@ -411,6 +425,9 @@ xfs_open_devices( struct block_device *logdev = NULL, *rtdev = NULL; int error; + if (dax_ddev) + fs_dax_register_holder(dax_ddev, mp, + &xfs_dax_holder_operations); /* * Open real time and log devices - order is important. */ @@ -419,6 +436,9 @@ xfs_open_devices( if (error) goto out; dax_logdev = fs_dax_get_by_bdev(logdev); + if (dax_logdev != dax_ddev && dax_logdev) + fs_dax_register_holder(dax_logdev, mp, + &xfs_dax_holder_operations); } if (mp->m_rtname) { @@ -433,6 +453,9 @@ xfs_open_devices( goto out_close_rtdev; } dax_rtdev = fs_dax_get_by_bdev(rtdev); + if (dax_rtdev) + fs_dax_register_holder(dax_rtdev, mp, + &xfs_dax_holder_operations); } /* @@ -1110,6 +1133,171 @@ xfs_fs_free_cached_objects( return xfs_reclaim_inodes_nr(XFS_M(sb), sc->nr_to_scan); } +struct notify_failure_info { + xfs_agblock_t startblock; + xfs_filblks_t blockcount; + int flags; +}; + +static loff_t +xfs_notify_failure_start( + struct xfs_mount *mp, + const struct xfs_rmap_irec *rec, + const struct notify_failure_info *notify) +{ + loff_t start = rec->rm_offset; + + if (notify->startblock > rec->rm_startblock) + start += XFS_FSB_TO_B(mp, + notify->startblock - rec->rm_startblock); + return start; +} + +static size_t +xfs_notify_failure_size( + struct xfs_mount *mp, + const struct xfs_rmap_irec *rec, + const struct notify_failure_info *notify) +{ + xfs_agblock_t rec_start = rec->rm_startblock; + xfs_agblock_t rec_end = rec->rm_startblock + rec->rm_blockcount; + xfs_agblock_t notify_start = notify->startblock; + xfs_agblock_t notify_end = notify->startblock + notify->blockcount; + xfs_agblock_t cross_start = max(rec_start, notify_start); + xfs_agblock_t cross_end = min(rec_end, notify_end); + + return XFS_FSB_TO_B(mp, cross_end - cross_start); +} + +static int +xfs_dax_notify_failure_fn( + struct xfs_btree_cur *cur, + const struct xfs_rmap_irec *rec, + void *data) +{ + struct xfs_mount *mp = cur->bc_mp; + struct xfs_inode *ip; + struct address_space *mapping; + struct notify_failure_info *notify = data; + int error = 0; + + if (XFS_RMAP_NON_INODE_OWNER(rec->rm_owner) || + (rec->rm_flags & (XFS_RMAP_ATTR_FORK | XFS_RMAP_BMBT_BLOCK))) { + // TODO check and try to fix metadata + xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_META); + return -EFSCORRUPTED; + } + + /* Get files that incore, filter out others that are not in use. */ + error = xfs_iget(mp, cur->bc_tp, rec->rm_owner, XFS_IGET_INCORE, + 0, &ip); + if (error) + return error; + + mapping = VFS_I(ip)->i_mapping; + if (IS_ENABLED(CONFIG_MEMORY_FAILURE)) { + loff_t offset = xfs_notify_failure_start(mp, rec, notify); + size_t size = xfs_notify_failure_size(mp, rec, notify); + + error = mf_dax_kill_procs(mapping, offset >> PAGE_SHIFT, size, + notify->flags); + } + // TODO try to fix data + xfs_irele(ip); + + return error; +} + +static loff_t +xfs_dax_bdev_offset( + struct xfs_mount *mp, + struct dax_device *dax_dev, + loff_t disk_offset) +{ + struct block_device *bdev; + + if (mp->m_ddev_targp->bt_daxdev == dax_dev) + bdev = mp->m_ddev_targp->bt_bdev; + else if (mp->m_logdev_targp->bt_daxdev == dax_dev) + bdev = mp->m_logdev_targp->bt_bdev; + else + bdev = mp->m_rtdev_targp->bt_bdev; + + return disk_offset - (get_start_sect(bdev) << SECTOR_SHIFT); +} + +static int +xfs_dax_notify_failure( + struct dax_device *dax_dev, + loff_t offset, + size_t len, + int flags) +{ + struct xfs_mount *mp = fs_dax_get_holder(dax_dev); + struct xfs_trans *tp = NULL; + struct xfs_btree_cur *cur = NULL; + struct xfs_buf *agf_bp = NULL; + struct xfs_rmap_irec rmap_low, rmap_high; + loff_t bdev_offset = xfs_dax_bdev_offset(mp, dax_dev, + offset); + xfs_fsblock_t fsbno = XFS_B_TO_FSB(mp, bdev_offset); + xfs_agnumber_t agno = XFS_FSB_TO_AGNO(mp, fsbno); + int error = 0; + struct notify_failure_info notify = { + .startblock = XFS_FSB_TO_AGBNO(mp, fsbno), + .blockcount = XFS_B_TO_FSB(mp, len), + .flags = flags, + }; + + if (mp->m_rtdev_targp && mp->m_rtdev_targp->bt_daxdev == dax_dev) { + xfs_warn(mp, + "notify_failure() not supported on realtime device!"); + return -EOPNOTSUPP; + } + + if (mp->m_logdev_targp && mp->m_logdev_targp->bt_daxdev == dax_dev && + mp->m_logdev_targp != mp->m_ddev_targp) { + xfs_err(mp, "ondisk log corrupt, shutting down fs!"); + xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_META); + return -EFSCORRUPTED; + } + + if (!xfs_has_rmapbt(mp)) { + xfs_warn(mp, "notify_failure() needs rmapbt enabled!"); + return -EOPNOTSUPP; + } + + error = xfs_trans_alloc_empty(mp, &tp); + if (error) + return error; + + error = xfs_alloc_read_agf(mp, tp, agno, 0, &agf_bp); + if (error) + goto out_cancel_tp; + + cur = xfs_rmapbt_init_cursor(mp, tp, agf_bp, agf_bp->b_pag); + + /* Construct a range for rmap query */ + memset(&rmap_low, 0, sizeof(rmap_low)); + memset(&rmap_high, 0xFF, sizeof(rmap_high)); + rmap_low.rm_startblock = rmap_high.rm_startblock = notify.startblock; + rmap_low.rm_blockcount = rmap_high.rm_blockcount = notify.blockcount; + + error = xfs_rmap_query_range(cur, &rmap_low, &rmap_high, + xfs_dax_notify_failure_fn, ¬ify); + + xfs_btree_del_cursor(cur, error); + xfs_trans_brelse(tp, agf_bp); + +out_cancel_tp: + xfs_trans_cancel(tp); + return error; +} + +static const struct dax_holder_operations xfs_dax_holder_operations = { + .notify_failure = xfs_dax_notify_failure, +}; + static const struct super_operations xfs_super_operations = { .alloc_inode = xfs_fs_alloc_inode, .destroy_inode = xfs_fs_destroy_inode, diff --git a/include/linux/dax.h b/include/linux/dax.h index 3d90becbd160..0f1fa7a4a616 100644 --- a/include/linux/dax.h +++ b/include/linux/dax.h @@ -149,6 +149,10 @@ static inline void fs_put_dax(struct dax_device *dax_dev) } struct dax_device *fs_dax_get_by_bdev(struct block_device *bdev); +void fs_dax_register_holder(struct dax_device *dax_dev, void *holder, + const struct dax_holder_operations *ops); +void fs_dax_unregister_holder(struct dax_device *dax_dev); +void *fs_dax_get_holder(struct dax_device *dax_dev); int dax_writeback_mapping_range(struct address_space *mapping, struct dax_device *dax_dev, struct writeback_control *wbc); @@ -179,6 +183,20 @@ static inline struct dax_device *fs_dax_get_by_bdev(struct block_device *bdev) return NULL; } +static inline void fs_dax_register_holder(struct dax_device *dax_dev, + void *holder, const struct dax_holder_operations *ops) +{ +} + +static inline void fs_dax_unregister_holder(struct dax_device *dax_dev) +{ +} + +static inline void *fs_dax_get_holder(struct dax_device *dax_dev) +{ + return NULL; +} + static inline struct page *dax_layout_busy_page(struct address_space *mapping) { return NULL;
This function is used to handle errors which may cause data lost in filesystem. Such as memory failure in fsdax mode. If the rmap feature of XFS enabled, we can query it to find files and metadata which are associated with the corrupt data. For now all we do is kill processes with that file mapped into their address spaces, but future patches could actually do something about corrupt metadata. After that, the memory failure needs to notify the processes who are using those files. Signed-off-by: Shiyang Ruan <ruansy.fnst@fujitsu.com> --- drivers/dax/super.c | 19 +++++ fs/xfs/xfs_fsops.c | 3 + fs/xfs/xfs_mount.h | 1 + fs/xfs/xfs_super.c | 188 ++++++++++++++++++++++++++++++++++++++++++++ include/linux/dax.h | 18 +++++ 5 files changed, 229 insertions(+)