| Message ID | 20210604011844.1756145-6-ruansy.fnst@fujitsu.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | fsdax: introduce fs query to support reflink | expand |
On Thu, Jun 3, 2021 at 6:19 PM Shiyang Ruan <ruansy.fnst@fujitsu.com> wrote: > > Call the ->memory_failure() which is implemented by pmem driver, in > order to finally notify filesystem to handle the corrupted data. The > handler which collects and kills processes are moved into > mf_dax_kill_procs(), which will be called by filesystem. > > Keep the old handler in order to roll back if driver or filesystem > does not support ->memory_failure()/->corrupted_range(). > > Signed-off-by: Shiyang Ruan <ruansy.fnst@fujitsu.com> > --- > block/genhd.c | 30 ++++++++++++++++++ > drivers/nvdimm/pmem.c | 14 +++++++++ > include/linux/genhd.h | 1 + > mm/memory-failure.c | 71 +++++++++++++++++++++++++++---------------- I would not expect a patch that converts the pmem driver to touch mm/memory-failure.c. mf_generic_kill_procs() has nothing to do with the pmem driver. > 4 files changed, 90 insertions(+), 26 deletions(-) > > diff --git a/block/genhd.c b/block/genhd.c > index 9f8cb7beaad1..75834bd057df 100644 > --- a/block/genhd.c > +++ b/block/genhd.c > @@ -718,6 +718,36 @@ struct block_device *bdget_disk(struct gendisk *disk, int partno) > return bdev; > } > > +/** > + * bdget_disk_sector - get block device by given sector number > + * @disk: gendisk of interest > + * @sector: sector number > + * > + * RETURNS: the found block device where sector locates in > + */ > +struct block_device *bdget_disk_sector(struct gendisk *disk, sector_t sector) > +{ > + struct block_device *part = NULL, *p; > + unsigned long idx; > + > + rcu_read_lock(); > + xa_for_each(&disk->part_tbl, idx, p) { > + if (p->bd_partno == 0) > + continue; > + if (p->bd_start_sect <= sector && > + sector < p->bd_start_sect + bdev_nr_sectors(p)) { > + part = p; > + break; > + } > + } > + rcu_read_unlock(); > + if (!part) > + part = disk->part0; > + > + return bdget_disk(disk, part->bd_partno); > +} > +EXPORT_SYMBOL(bdget_disk_sector); I can't see any justification for this function. The pmem driver does not need it and the upper layer holders should have their own mechanism to go from dax_dev offset to bdev if they need to, but hopefully they don't. A dax_device failure should be independent of a block_device failure. > + > /* > * print a full list of all partitions - intended for places where the root > * filesystem can't be mounted and thus to give the victim some idea of what > diff --git a/drivers/nvdimm/pmem.c b/drivers/nvdimm/pmem.c > index ed10a8b66068..98349e7d0a28 100644 > --- a/drivers/nvdimm/pmem.c > +++ b/drivers/nvdimm/pmem.c > @@ -364,9 +364,23 @@ static void pmem_release_disk(void *__pmem) > put_disk(pmem->disk); > } > > +static int pmem_pagemap_memory_failure(struct dev_pagemap *pgmap, > + unsigned long pfn, int flags) > +{ > + struct pmem_device *pdev = > + container_of(pgmap, struct pmem_device, pgmap); This local variable is called @pmem not @pdev in other parts of the driver. > + loff_t offset = PFN_PHYS(pfn) - pdev->phys_addr - pdev->data_offset; > + struct block_device *bdev = > + bdget_disk_sector(pdev->disk, offset >> SECTOR_SHIFT); > + > + return dax_corrupted_range(pdev->dax_dev, bdev, offset, > + page_size(pfn_to_page(pfn)), &flags); Per previous comments this interface should be range based. Why is the last argument &flags? That was passed in by value so any changes to it will not be reflected back to memory_failure()? > +} > + > static const struct dev_pagemap_ops fsdax_pagemap_ops = { > .kill = pmem_pagemap_kill, > .cleanup = pmem_pagemap_cleanup, > + .memory_failure = pmem_pagemap_memory_failure, > }; > > static int pmem_attach_disk(struct device *dev, > diff --git a/include/linux/genhd.h b/include/linux/genhd.h > index 6fc26f7bdf71..2ad70c02c343 100644 > --- a/include/linux/genhd.h > +++ b/include/linux/genhd.h > @@ -219,6 +219,7 @@ static inline void add_disk_no_queue_reg(struct gendisk *disk) > > extern void del_gendisk(struct gendisk *gp); > extern struct block_device *bdget_disk(struct gendisk *disk, int partno); > +extern struct block_device *bdget_disk_sector(struct gendisk *disk, sector_t sector); > > void set_disk_ro(struct gendisk *disk, bool read_only); > > diff --git a/mm/memory-failure.c b/mm/memory-failure.c > index 4377e727d478..43017d7f3918 100644 > --- a/mm/memory-failure.c > +++ b/mm/memory-failure.c > @@ -1247,6 +1247,36 @@ static void unmap_and_kill(struct list_head *to_kill, unsigned long pfn, > kill_procs(to_kill, flags & MF_MUST_KILL, false, pfn, flags); > } > > +static int mf_generic_kill_procs(unsigned long long pfn, int flags) > +{ > + struct page *page = pfn_to_page(pfn); > + LIST_HEAD(to_kill); > + dax_entry_t cookie; > + > + /* > + * Prevent the inode from being freed while we are interrogating > + * the address_space, typically this would be handled by > + * lock_page(), but dax pages do not use the page lock. This > + * also prevents changes to the mapping of this pfn until > + * poison signaling is complete. > + */ > + cookie = dax_lock_page(page); > + if (!cookie) > + return -EBUSY; > + /* > + * Unlike System-RAM there is no possibility to swap in a > + * different physical page at a given virtual address, so all > + * userspace consumption of ZONE_DEVICE memory necessitates > + * SIGBUS (i.e. MF_MUST_KILL) > + */ > + flags |= MF_ACTION_REQUIRED | MF_MUST_KILL; > + collect_procs(page, &to_kill, flags & MF_ACTION_REQUIRED); > + > + unmap_and_kill(&to_kill, pfn, page->mapping, page->index, flags); > + dax_unlock_page(page, cookie); > + return 0; > +} > + Per above, I am surprised to find this in this patch, it belong in its own patch if at all. > int mf_dax_kill_procs(struct address_space *mapping, pgoff_t index, int flags) > { > LIST_HEAD(to_kill); > @@ -1348,9 +1378,7 @@ static int memory_failure_dev_pagemap(unsigned long pfn, int flags, > struct dev_pagemap *pgmap) > { > struct page *page = pfn_to_page(pfn); > - LIST_HEAD(to_kill); > int rc = -EBUSY; > - dax_entry_t cookie; > > if (flags & MF_COUNT_INCREASED) > /* > @@ -1364,20 +1392,9 @@ static int memory_failure_dev_pagemap(unsigned long pfn, int flags, > goto out; > } > > - /* > - * Prevent the inode from being freed while we are interrogating > - * the address_space, typically this would be handled by > - * lock_page(), but dax pages do not use the page lock. This > - * also prevents changes to the mapping of this pfn until > - * poison signaling is complete. > - */ > - cookie = dax_lock_page(page); > - if (!cookie) > - goto out; > - > if (hwpoison_filter(page)) { > rc = 0; > - goto unlock; > + goto out; > } > > if (pgmap->type == MEMORY_DEVICE_PRIVATE) { > @@ -1385,7 +1402,7 @@ static int memory_failure_dev_pagemap(unsigned long pfn, int flags, > * TODO: Handle HMM pages which may need coordination > * with device-side memory. > */ > - goto unlock; > + goto out; > } > > /* > @@ -1395,19 +1412,21 @@ static int memory_failure_dev_pagemap(unsigned long pfn, int flags, > SetPageHWPoison(page); > > /* > - * Unlike System-RAM there is no possibility to swap in a > - * different physical page at a given virtual address, so all > - * userspace consumption of ZONE_DEVICE memory necessitates > - * SIGBUS (i.e. MF_MUST_KILL) > + * Call driver's implementation to handle the memory failure, > + * otherwise roll back to generic handler. > */ > - flags |= MF_ACTION_REQUIRED | MF_MUST_KILL; > - collect_procs_file(page, page->mapping, page->index, &to_kill, > - flags & MF_ACTION_REQUIRED); > + if (pgmap->ops->memory_failure) { > + rc = pgmap->ops->memory_failure(pgmap, pfn, flags); > + /* > + * Roll back to generic handler too if operation is not > + * supported inside the driver/device/filesystem. > + */ > + if (rc != EOPNOTSUPP) > + goto out; > + } > + > + rc = mf_generic_kill_procs(pfn, flags); > > - unmap_and_kill(&to_kill, pfn, page->mapping, page->index, flags); > - rc = 0; > -unlock: > - dax_unlock_page(page, cookie); > out: > /* drop pgmap ref acquired in caller */ > put_dev_pagemap(pgmap); > -- > 2.31.1 > > >
diff --git a/block/genhd.c b/block/genhd.c index 9f8cb7beaad1..75834bd057df 100644 --- a/block/genhd.c +++ b/block/genhd.c @@ -718,6 +718,36 @@ struct block_device *bdget_disk(struct gendisk *disk, int partno) return bdev; } +/** + * bdget_disk_sector - get block device by given sector number + * @disk: gendisk of interest + * @sector: sector number + * + * RETURNS: the found block device where sector locates in + */ +struct block_device *bdget_disk_sector(struct gendisk *disk, sector_t sector) +{ + struct block_device *part = NULL, *p; + unsigned long idx; + + rcu_read_lock(); + xa_for_each(&disk->part_tbl, idx, p) { + if (p->bd_partno == 0) + continue; + if (p->bd_start_sect <= sector && + sector < p->bd_start_sect + bdev_nr_sectors(p)) { + part = p; + break; + } + } + rcu_read_unlock(); + if (!part) + part = disk->part0; + + return bdget_disk(disk, part->bd_partno); +} +EXPORT_SYMBOL(bdget_disk_sector); + /* * print a full list of all partitions - intended for places where the root * filesystem can't be mounted and thus to give the victim some idea of what diff --git a/drivers/nvdimm/pmem.c b/drivers/nvdimm/pmem.c index ed10a8b66068..98349e7d0a28 100644 --- a/drivers/nvdimm/pmem.c +++ b/drivers/nvdimm/pmem.c @@ -364,9 +364,23 @@ static void pmem_release_disk(void *__pmem) put_disk(pmem->disk); } +static int pmem_pagemap_memory_failure(struct dev_pagemap *pgmap, + unsigned long pfn, int flags) +{ + struct pmem_device *pdev = + container_of(pgmap, struct pmem_device, pgmap); + loff_t offset = PFN_PHYS(pfn) - pdev->phys_addr - pdev->data_offset; + struct block_device *bdev = + bdget_disk_sector(pdev->disk, offset >> SECTOR_SHIFT); + + return dax_corrupted_range(pdev->dax_dev, bdev, offset, + page_size(pfn_to_page(pfn)), &flags); +} + static const struct dev_pagemap_ops fsdax_pagemap_ops = { .kill = pmem_pagemap_kill, .cleanup = pmem_pagemap_cleanup, + .memory_failure = pmem_pagemap_memory_failure, }; static int pmem_attach_disk(struct device *dev, diff --git a/include/linux/genhd.h b/include/linux/genhd.h index 6fc26f7bdf71..2ad70c02c343 100644 --- a/include/linux/genhd.h +++ b/include/linux/genhd.h @@ -219,6 +219,7 @@ static inline void add_disk_no_queue_reg(struct gendisk *disk) extern void del_gendisk(struct gendisk *gp); extern struct block_device *bdget_disk(struct gendisk *disk, int partno); +extern struct block_device *bdget_disk_sector(struct gendisk *disk, sector_t sector); void set_disk_ro(struct gendisk *disk, bool read_only); diff --git a/mm/memory-failure.c b/mm/memory-failure.c index 4377e727d478..43017d7f3918 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -1247,6 +1247,36 @@ static void unmap_and_kill(struct list_head *to_kill, unsigned long pfn, kill_procs(to_kill, flags & MF_MUST_KILL, false, pfn, flags); } +static int mf_generic_kill_procs(unsigned long long pfn, int flags) +{ + struct page *page = pfn_to_page(pfn); + LIST_HEAD(to_kill); + dax_entry_t cookie; + + /* + * Prevent the inode from being freed while we are interrogating + * the address_space, typically this would be handled by + * lock_page(), but dax pages do not use the page lock. This + * also prevents changes to the mapping of this pfn until + * poison signaling is complete. + */ + cookie = dax_lock_page(page); + if (!cookie) + return -EBUSY; + /* + * Unlike System-RAM there is no possibility to swap in a + * different physical page at a given virtual address, so all + * userspace consumption of ZONE_DEVICE memory necessitates + * SIGBUS (i.e. MF_MUST_KILL) + */ + flags |= MF_ACTION_REQUIRED | MF_MUST_KILL; + collect_procs(page, &to_kill, flags & MF_ACTION_REQUIRED); + + unmap_and_kill(&to_kill, pfn, page->mapping, page->index, flags); + dax_unlock_page(page, cookie); + return 0; +} + int mf_dax_kill_procs(struct address_space *mapping, pgoff_t index, int flags) { LIST_HEAD(to_kill); @@ -1348,9 +1378,7 @@ static int memory_failure_dev_pagemap(unsigned long pfn, int flags, struct dev_pagemap *pgmap) { struct page *page = pfn_to_page(pfn); - LIST_HEAD(to_kill); int rc = -EBUSY; - dax_entry_t cookie; if (flags & MF_COUNT_INCREASED) /* @@ -1364,20 +1392,9 @@ static int memory_failure_dev_pagemap(unsigned long pfn, int flags, goto out; } - /* - * Prevent the inode from being freed while we are interrogating - * the address_space, typically this would be handled by - * lock_page(), but dax pages do not use the page lock. This - * also prevents changes to the mapping of this pfn until - * poison signaling is complete. - */ - cookie = dax_lock_page(page); - if (!cookie) - goto out; - if (hwpoison_filter(page)) { rc = 0; - goto unlock; + goto out; } if (pgmap->type == MEMORY_DEVICE_PRIVATE) { @@ -1385,7 +1402,7 @@ static int memory_failure_dev_pagemap(unsigned long pfn, int flags, * TODO: Handle HMM pages which may need coordination * with device-side memory. */ - goto unlock; + goto out; } /* @@ -1395,19 +1412,21 @@ static int memory_failure_dev_pagemap(unsigned long pfn, int flags, SetPageHWPoison(page); /* - * Unlike System-RAM there is no possibility to swap in a - * different physical page at a given virtual address, so all - * userspace consumption of ZONE_DEVICE memory necessitates - * SIGBUS (i.e. MF_MUST_KILL) + * Call driver's implementation to handle the memory failure, + * otherwise roll back to generic handler. */ - flags |= MF_ACTION_REQUIRED | MF_MUST_KILL; - collect_procs_file(page, page->mapping, page->index, &to_kill, - flags & MF_ACTION_REQUIRED); + if (pgmap->ops->memory_failure) { + rc = pgmap->ops->memory_failure(pgmap, pfn, flags); + /* + * Roll back to generic handler too if operation is not + * supported inside the driver/device/filesystem. + */ + if (rc != EOPNOTSUPP) + goto out; + } + + rc = mf_generic_kill_procs(pfn, flags); - unmap_and_kill(&to_kill, pfn, page->mapping, page->index, flags); - rc = 0; -unlock: - dax_unlock_page(page, cookie); out: /* drop pgmap ref acquired in caller */ put_dev_pagemap(pgmap);
Call the ->memory_failure() which is implemented by pmem driver, in order to finally notify filesystem to handle the corrupted data. The handler which collects and kills processes are moved into mf_dax_kill_procs(), which will be called by filesystem. Keep the old handler in order to roll back if driver or filesystem does not support ->memory_failure()/->corrupted_range(). Signed-off-by: Shiyang Ruan <ruansy.fnst@fujitsu.com> --- block/genhd.c | 30 ++++++++++++++++++ drivers/nvdimm/pmem.c | 14 +++++++++ include/linux/genhd.h | 1 + mm/memory-failure.c | 71 +++++++++++++++++++++++++++---------------- 4 files changed, 90 insertions(+), 26 deletions(-)