#include <linux/uio.h>
#include <linux/vmstat.h>
+/*
+ * dax_clear_blocks() is called from within transaction context from XFS,
+ * and hence this means the stack from this point must follow GFP_NOFS
+ * semantics for all operations.
+ */
int dax_clear_blocks(struct inode *inode, sector_t block, long size)
{
struct block_device *bdev = inode->i_sb->s_bdev;
* Try near allocation first, then anywhere-in-ag after
* the first a.g. fails.
*/
- if ((args->userdata == XFS_ALLOC_INITIAL_USER_DATA) &&
+ if ((args->userdata & XFS_ALLOC_INITIAL_USER_DATA) &&
(mp->m_flags & XFS_MOUNT_32BITINODES)) {
args->fsbno = XFS_AGB_TO_FSB(mp,
((mp->m_agfrotor / rotorstep) %
XFS_AG_CHECK_DADDR(mp, XFS_FSB_TO_DADDR(mp, args->fsbno),
args->len);
#endif
+
+ /* Zero the extent if we were asked to do so */
+ if (args->userdata & XFS_ALLOC_USERDATA_ZERO) {
+ error = xfs_zero_extent(args->ip, args->fsbno, args->len);
+ if (error)
+ goto error0;
+ }
+
}
xfs_perag_put(args->pag);
return 0;
struct xfs_mount *mp; /* file system mount point */
struct xfs_buf *agbp; /* buffer for a.g. freelist header */
struct xfs_perag *pag; /* per-ag struct for this agno */
+ struct xfs_inode *ip; /* for userdata zeroing method */
xfs_fsblock_t fsbno; /* file system block number */
xfs_agnumber_t agno; /* allocation group number */
xfs_agblock_t agbno; /* allocation group-relative block # */
char wasdel; /* set if allocation was prev delayed */
char wasfromfl; /* set if allocation is from freelist */
char isfl; /* set if is freelist blocks - !acctg */
- char userdata; /* set if this is user data */
+ char userdata; /* mask defining userdata treatment */
xfs_fsblock_t firstblock; /* io first block allocated */
} xfs_alloc_arg_t;
/*
* Defines for userdata
*/
-#define XFS_ALLOC_USERDATA 1 /* allocation is for user data*/
-#define XFS_ALLOC_INITIAL_USER_DATA 2 /* special case start of file */
+#define XFS_ALLOC_USERDATA (1 << 0)/* allocation is for user data*/
+#define XFS_ALLOC_INITIAL_USER_DATA (1 << 1)/* special case start of file */
+#define XFS_ALLOC_USERDATA_ZERO (1 << 2)/* zero extent on allocation */
xfs_extlen_t xfs_alloc_longest_free_extent(struct xfs_mount *mp,
struct xfs_perag *pag, xfs_extlen_t need);
args.wasdel = ap->wasdel;
args.isfl = 0;
args.userdata = ap->userdata;
- if ((error = xfs_alloc_vextent(&args)))
+ if (ap->userdata & XFS_ALLOC_USERDATA_ZERO)
+ args.ip = ap->ip;
+
+ error = xfs_alloc_vextent(&args);
+ if (error)
return error;
+
if (tryagain && args.fsbno == NULLFSBLOCK) {
/*
* Exact allocation failed. Now try with alignment
/*
* Indicate if this is the first user data in the file, or just any
- * user data.
+ * user data. And if it is userdata, indicate whether it needs to
+ * be initialised to zero during allocation.
*/
if (!(bma->flags & XFS_BMAPI_METADATA)) {
bma->userdata = (bma->offset == 0) ?
XFS_ALLOC_INITIAL_USER_DATA : XFS_ALLOC_USERDATA;
+ if (bma->flags & XFS_BMAPI_ZERO)
+ bma->userdata |= XFS_ALLOC_USERDATA_ZERO;
}
bma->minlen = (bma->flags & XFS_BMAPI_CONTIG) ? bma->length : 1;
mval->br_state = (mval->br_state == XFS_EXT_UNWRITTEN)
? XFS_EXT_NORM : XFS_EXT_UNWRITTEN;
+ /*
+ * Before insertion into the bmbt, zero the range being converted
+ * if required.
+ */
+ if (flags & XFS_BMAPI_ZERO) {
+ error = xfs_zero_extent(bma->ip, mval->br_startblock,
+ mval->br_blockcount);
+ if (error)
+ return error;
+ }
+
error = xfs_bmap_add_extent_unwritten_real(bma->tp, bma->ip, &bma->idx,
&bma->cur, mval, bma->firstblock, bma->flist,
&tmp_logflags);
ASSERT(XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_LOCAL);
ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
+ /* zeroing is for currently only for data extents, not metadata */
+ ASSERT((flags & (XFS_BMAPI_METADATA | XFS_BMAPI_ZERO)) !=
+ (XFS_BMAPI_METADATA | XFS_BMAPI_ZERO));
+ /*
+ * we can allocate unwritten extents or pre-zero allocated blocks,
+ * but it makes no sense to do both at once. This would result in
+ * zeroing the unwritten extent twice, but it still being an
+ * unwritten extent....
+ */
+ ASSERT((flags & (XFS_BMAPI_PREALLOC | XFS_BMAPI_ZERO)) !=
+ (XFS_BMAPI_PREALLOC | XFS_BMAPI_ZERO));
+
if (unlikely(XFS_TEST_ERROR(
(XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_EXTENTS &&
XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_BTREE),
xfs_extlen_t minleft; /* amount must be left after alloc */
bool eof; /* set if allocating past last extent */
bool wasdel; /* replacing a delayed allocation */
- bool userdata;/* set if is user data */
bool aeof; /* allocated space at eof */
bool conv; /* overwriting unwritten extents */
+ char userdata;/* userdata mask */
int flags;
};
*/
#define XFS_BMAPI_CONVERT 0x040
+/*
+ * allocate zeroed extents - this requires all newly allocated user data extents
+ * to be initialised to zero. It will be ignored if XFS_BMAPI_METADATA is set.
+ * Use in conjunction with XFS_BMAPI_CONVERT to convert unwritten extents found
+ * during the allocation range to zeroed written extents.
+ */
+#define XFS_BMAPI_ZERO 0x080
+
#define XFS_BMAPI_FLAGS \
{ XFS_BMAPI_ENTIRE, "ENTIRE" }, \
{ XFS_BMAPI_METADATA, "METADATA" }, \
{ XFS_BMAPI_PREALLOC, "PREALLOC" }, \
{ XFS_BMAPI_IGSTATE, "IGSTATE" }, \
{ XFS_BMAPI_CONTIG, "CONTIG" }, \
- { XFS_BMAPI_CONVERT, "CONVERT" }
+ { XFS_BMAPI_CONVERT, "CONVERT" }, \
+ { XFS_BMAPI_ZERO, "ZERO" }
static inline int xfs_bmapi_aflag(int w)
* the DIO. There is only going to be one reference to the ioend and its life
* cycle is constrained by the DIO completion code. hence we don't need
* reference counting here.
+ *
+ * Note that for DIO, an IO to the highest supported file block offset (i.e.
+ * 2^63 - 1FSB bytes) will result in the offset + count overflowing a signed 64
+ * bit variable. Hence if we see this overflow, we have to assume that the IO is
+ * extending the file size. We won't know for sure until IO completion is run
+ * and the actual max write offset is communicated to the IO completion
+ * routine.
+ *
+ * For DAX page faults, we are preparing to never see unwritten extents here,
+ * nor should we ever extend the inode size. Hence we will soon have nothing to
+ * do here for this case, ensuring we don't have to provide an IO completion
+ * callback to free an ioend that we don't actually need for a fault into the
+ * page at offset (2^63 - 1FSB) bytes.
*/
+
static void
xfs_map_direct(
struct inode *inode,
struct buffer_head *bh_result,
struct xfs_bmbt_irec *imap,
- xfs_off_t offset)
+ xfs_off_t offset,
+ bool dax_fault)
{
struct xfs_ioend *ioend;
xfs_off_t size = bh_result->b_size;
trace_xfs_gbmap_direct(XFS_I(inode), offset, size, type, imap);
+ if (dax_fault) {
+ ASSERT(type == XFS_IO_OVERWRITE);
+ trace_xfs_gbmap_direct_none(XFS_I(inode), offset, size, type,
+ imap);
+ return;
+ }
+
if (bh_result->b_private) {
ioend = bh_result->b_private;
ASSERT(ioend->io_size > 0);
ioend->io_size, ioend->io_type,
imap);
} else if (type == XFS_IO_UNWRITTEN ||
- offset + size > i_size_read(inode)) {
+ offset + size > i_size_read(inode) ||
+ offset + size < 0) {
ioend = xfs_alloc_ioend(inode, type);
ioend->io_offset = offset;
ioend->io_size = size;
sector_t iblock,
struct buffer_head *bh_result,
int create,
- bool direct)
+ bool direct,
+ bool dax_fault)
{
struct xfs_inode *ip = XFS_I(inode);
struct xfs_mount *mp = ip->i_mount;
if (error)
goto out_unlock;
+ /* for DAX, we convert unwritten extents directly */
if (create &&
(!nimaps ||
(imap.br_startblock == HOLESTARTBLOCK ||
- imap.br_startblock == DELAYSTARTBLOCK))) {
+ imap.br_startblock == DELAYSTARTBLOCK) ||
+ (IS_DAX(inode) && ISUNWRITTEN(&imap)))) {
if (direct || xfs_get_extsz_hint(ip)) {
/*
* xfs_iomap_write_direct() expects the shared lock. It
goto out_unlock;
}
+ if (IS_DAX(inode) && create) {
+ ASSERT(!ISUNWRITTEN(&imap));
+ /* zeroing is not needed at a higher layer */
+ new = 0;
+ }
+
/* trim mapping down to size requested */
if (direct || size > (1 << inode->i_blkbits))
xfs_map_trim_size(inode, iblock, bh_result,
set_buffer_unwritten(bh_result);
/* direct IO needs special help */
if (create && direct)
- xfs_map_direct(inode, bh_result, &imap, offset);
+ xfs_map_direct(inode, bh_result, &imap, offset,
+ dax_fault);
}
/*
struct buffer_head *bh_result,
int create)
{
- return __xfs_get_blocks(inode, iblock, bh_result, create, false);
+ return __xfs_get_blocks(inode, iblock, bh_result, create, false, false);
}
int
struct buffer_head *bh_result,
int create)
{
- return __xfs_get_blocks(inode, iblock, bh_result, create, true);
+ return __xfs_get_blocks(inode, iblock, bh_result, create, true, false);
+}
+
+int
+xfs_get_blocks_dax_fault(
+ struct inode *inode,
+ sector_t iblock,
+ struct buffer_head *bh_result,
+ int create)
+{
+ return __xfs_get_blocks(inode, iblock, bh_result, create, true, true);
}
static void
__xfs_end_io_direct_write(inode, ioend, offset, size);
}
-/*
- * For DAX we need a mapping buffer callback for unwritten extent conversion
- * when page faults allocate blocks and then zero them. Note that in this
- * case the mapping indicated by the ioend may extend beyond EOF. We most
- * definitely do not want to extend EOF here, so we trim back the ioend size to
- * EOF.
- */
-#ifdef CONFIG_FS_DAX
-void
-xfs_end_io_dax_write(
- struct buffer_head *bh,
- int uptodate)
-{
- struct xfs_ioend *ioend = bh->b_private;
- struct inode *inode = ioend->io_inode;
- ssize_t size = ioend->io_size;
-
- ASSERT(IS_DAX(ioend->io_inode));
-
- /* if there was an error zeroing, then don't convert it */
- if (!uptodate)
- ioend->io_error = -EIO;
-
- /*
- * Trim update to EOF, so we don't extend EOF during unwritten extent
- * conversion of partial EOF blocks.
- */
- spin_lock(&XFS_I(inode)->i_flags_lock);
- if (ioend->io_offset + size > i_size_read(inode))
- size = i_size_read(inode) - ioend->io_offset;
- spin_unlock(&XFS_I(inode)->i_flags_lock);
-
- __xfs_end_io_direct_write(inode, ioend, ioend->io_offset, size);
-
-}
-#else
-void xfs_end_io_dax_write(struct buffer_head *bh, int uptodate) { }
-#endif
-
static inline ssize_t
xfs_vm_do_dio(
struct inode *inode,
struct buffer_head *map_bh, int create);
int xfs_get_blocks_direct(struct inode *inode, sector_t offset,
struct buffer_head *map_bh, int create);
-void xfs_end_io_dax_write(struct buffer_head *bh, int uptodate);
+int xfs_get_blocks_dax_fault(struct inode *inode, sector_t offset,
+ struct buffer_head *map_bh, int create);
extern void xfs_count_page_state(struct page *, int *, int *);
XFS_FSB_TO_DADDR((ip)->i_mount, (fsb)));
}
+/*
+ * Routine to zero an extent on disk allocated to the specific inode.
+ *
+ * The VFS functions take a linearised filesystem block offset, so we have to
+ * convert the sparse xfs fsb to the right format first.
+ * VFS types are real funky, too.
+ */
+int
+xfs_zero_extent(
+ struct xfs_inode *ip,
+ xfs_fsblock_t start_fsb,
+ xfs_off_t count_fsb)
+{
+ struct xfs_mount *mp = ip->i_mount;
+ xfs_daddr_t sector = xfs_fsb_to_db(ip, start_fsb);
+ sector_t block = XFS_BB_TO_FSBT(mp, sector);
+ ssize_t size = XFS_FSB_TO_B(mp, count_fsb);
+
+ if (IS_DAX(VFS_I(ip)))
+ return dax_clear_blocks(VFS_I(ip), block, size);
+
+ /*
+ * let the block layer decide on the fastest method of
+ * implementing the zeroing.
+ */
+ return sb_issue_zeroout(mp->m_super, block, count_fsb, GFP_NOFS);
+
+}
+
/*
* Routine to be called at transaction's end by xfs_bmapi, xfs_bunmapi
* caller. Frees all the extents that need freeing, which must be done
xfs_trans_mod_dquot_byino(ap->tp, ap->ip,
ap->wasdel ? XFS_TRANS_DQ_DELRTBCOUNT :
XFS_TRANS_DQ_RTBCOUNT, (long) ralen);
+
+ /* Zero the extent if we were asked to do so */
+ if (ap->userdata & XFS_ALLOC_USERDATA_ZERO) {
+ error = xfs_zero_extent(ap->ip, ap->blkno, ap->length);
+ if (error)
+ return error;
+ }
} else {
ap->length = 0;
}
*
* mmap_sem (MM)
* sb_start_pagefault(vfs, freeze)
- * i_mmap_lock (XFS - truncate serialisation)
+ * i_mmaplock (XFS - truncate serialisation)
* page_lock (MM)
* i_lock (XFS - extent map serialisation)
*/
xfs_ilock(XFS_I(inode), XFS_MMAPLOCK_SHARED);
if (IS_DAX(inode)) {
- ret = __dax_mkwrite(vma, vmf, xfs_get_blocks_direct,
- xfs_end_io_dax_write);
+ ret = __dax_mkwrite(vma, vmf, xfs_get_blocks_dax_fault, NULL);
} else {
ret = __block_page_mkwrite(vma, vmf, xfs_get_blocks);
ret = block_page_mkwrite_return(ret);
* changes to xfs_get_blocks_direct() to map unwritten extent
* ioend for conversion on read-only mappings.
*/
- ret = __dax_fault(vma, vmf, xfs_get_blocks_direct, NULL);
+ ret = __dax_fault(vma, vmf, xfs_get_blocks_dax_fault, NULL);
} else
ret = filemap_fault(vma, vmf);
xfs_iunlock(XFS_I(inode), XFS_MMAPLOCK_SHARED);
return ret;
}
+/*
+ * Similar to xfs_filemap_fault(), the DAX fault path can call into here on
+ * both read and write faults. Hence we need to handle both cases. There is no
+ * ->pmd_mkwrite callout for huge pages, so we have a single function here to
+ * handle both cases here. @flags carries the information on the type of fault
+ * occuring.
+ */
STATIC int
xfs_filemap_pmd_fault(
struct vm_area_struct *vma,
trace_xfs_filemap_pmd_fault(ip);
- sb_start_pagefault(inode->i_sb);
- file_update_time(vma->vm_file);
+ if (flags & FAULT_FLAG_WRITE) {
+ sb_start_pagefault(inode->i_sb);
+ file_update_time(vma->vm_file);
+ }
+
xfs_ilock(XFS_I(inode), XFS_MMAPLOCK_SHARED);
- ret = __dax_pmd_fault(vma, addr, pmd, flags, xfs_get_blocks_direct,
- xfs_end_io_dax_write);
+ ret = __dax_pmd_fault(vma, addr, pmd, flags, xfs_get_blocks_dax_fault,
+ NULL);
xfs_iunlock(XFS_I(inode), XFS_MMAPLOCK_SHARED);
- sb_end_pagefault(inode->i_sb);
+ if (flags & FAULT_FLAG_WRITE)
+ sb_end_pagefault(inode->i_sb);
+
+ return ret;
+}
+
+/*
+ * pfn_mkwrite was originally inteneded to ensure we capture time stamp
+ * updates on write faults. In reality, it's need to serialise against
+ * truncate similar to page_mkwrite. Hence we open-code dax_pfn_mkwrite()
+ * here and cycle the XFS_MMAPLOCK_SHARED to ensure we serialise the fault
+ * barrier in place.
+ */
+static int
+xfs_filemap_pfn_mkwrite(
+ struct vm_area_struct *vma,
+ struct vm_fault *vmf)
+{
+
+ struct inode *inode = file_inode(vma->vm_file);
+ struct xfs_inode *ip = XFS_I(inode);
+ int ret = VM_FAULT_NOPAGE;
+ loff_t size;
+
+ trace_xfs_filemap_pfn_mkwrite(ip);
+
+ sb_start_pagefault(inode->i_sb);
+ file_update_time(vma->vm_file);
+
+ /* check if the faulting page hasn't raced with truncate */
+ xfs_ilock(ip, XFS_MMAPLOCK_SHARED);
+ size = (i_size_read(inode) + PAGE_SIZE - 1) >> PAGE_SHIFT;
+ if (vmf->pgoff >= size)
+ ret = VM_FAULT_SIGBUS;
+ xfs_iunlock(ip, XFS_MMAPLOCK_SHARED);
+ sb_end_pagefault(inode->i_sb);
return ret;
+
}
static const struct vm_operations_struct xfs_file_vm_ops = {
.pmd_fault = xfs_filemap_pmd_fault,
.map_pages = filemap_map_pages,
.page_mkwrite = xfs_filemap_page_mkwrite,
+ .pfn_mkwrite = xfs_filemap_pfn_mkwrite,
};
STATIC int
int committed;
int error;
int lockmode;
+ int bmapi_flags = XFS_BMAPI_PREALLOC;
rt = XFS_IS_REALTIME_INODE(ip);
extsz = xfs_get_extsz_hint(ip);
* Allocate and setup the transaction
*/
tp = xfs_trans_alloc(mp, XFS_TRANS_DIOSTRAT);
+
+ /*
+ * For DAX, we do not allocate unwritten extents, but instead we zero
+ * the block before we commit the transaction. Ideally we'd like to do
+ * this outside the transaction context, but if we commit and then crash
+ * we may not have zeroed the blocks and this will be exposed on
+ * recovery of the allocation. Hence we must zero before commit.
+ * Further, if we are mapping unwritten extents here, we need to zero
+ * and convert them to written so that we don't need an unwritten extent
+ * callback for DAX. This also means that we need to be able to dip into
+ * the reserve block pool if there is no space left but we need to do
+ * unwritten extent conversion.
+ */
+ if (IS_DAX(VFS_I(ip))) {
+ bmapi_flags = XFS_BMAPI_CONVERT | XFS_BMAPI_ZERO;
+ tp->t_flags |= XFS_TRANS_RESERVE;
+ }
error = xfs_trans_reserve(tp, &M_RES(mp)->tr_write,
resblks, resrtextents);
/*
xfs_bmap_init(&free_list, &firstfsb);
nimaps = 1;
error = xfs_bmapi_write(tp, ip, offset_fsb, count_fsb,
- XFS_BMAPI_PREALLOC, &firstfsb, resblks, imap,
+ bmapi_flags, &firstfsb, resblks, imap,
&nimaps, &free_list);
if (error)
goto out_bmap_cancel;
error = xfs_bmap_finish(&tp, &free_list, &committed);
if (error)
goto out_bmap_cancel;
+
error = xfs_trans_commit(tp);
if (error)
goto out_unlock;
extern void xfs_set_low_space_thresholds(struct xfs_mount *);
+int xfs_zero_extent(struct xfs_inode *ip, xfs_fsblock_t start_fsb,
+ xfs_off_t count_fsb);
+
#endif /* __XFS_MOUNT_H__ */
DEFINE_INODE_EVENT(xfs_filemap_fault);
DEFINE_INODE_EVENT(xfs_filemap_pmd_fault);
DEFINE_INODE_EVENT(xfs_filemap_page_mkwrite);
+DEFINE_INODE_EVENT(xfs_filemap_pfn_mkwrite);
DECLARE_EVENT_CLASS(xfs_iref_class,
TP_PROTO(struct xfs_inode *ip, unsigned long caller_ip),
projects / karo-tx-linux.git / commitdiff