/**
* attrib.c - NTFS attribute operations. Part of the Linux-NTFS project.
*
- * Copyright (c) 2001-2004 Anton Altaparmakov
+ * Copyright (c) 2001-2006 Anton Altaparmakov
* Copyright (c) 2002 Richard Russon
*
* This program/include file is free software; you can redistribute it and/or
*/
#include <linux/buffer_head.h>
+#include <linux/sched.h>
+#include <linux/swap.h>
+#include <linux/writeback.h>
#include "attrib.h"
#include "debug.h"
#include "layout.h"
+#include "lcnalloc.h"
+#include "malloc.h"
#include "mft.h"
#include "ntfs.h"
#include "types.h"
/**
- * ntfs_map_runlist - map (a part of) a runlist of an ntfs inode
+ * ntfs_map_runlist_nolock - map (a part of) a runlist of an ntfs inode
* @ni: ntfs inode for which to map (part of) a runlist
* @vcn: map runlist part containing this vcn
+ * @ctx: active attribute search context if present or NULL if not
*
* Map the part of a runlist containing the @vcn of the ntfs inode @ni.
*
- * Return 0 on success and -errno on error.
+ * If @ctx is specified, it is an active search context of @ni and its base mft
+ * record. This is needed when ntfs_map_runlist_nolock() encounters unmapped
+ * runlist fragments and allows their mapping. If you do not have the mft
+ * record mapped, you can specify @ctx as NULL and ntfs_map_runlist_nolock()
+ * will perform the necessary mapping and unmapping.
*
- * Locking: - The runlist must be unlocked on entry and is unlocked on return.
- * - This function takes the lock for writing and modifies the runlist.
+ * Note, ntfs_map_runlist_nolock() saves the state of @ctx on entry and
+ * restores it before returning. Thus, @ctx will be left pointing to the same
+ * attribute on return as on entry. However, the actual pointers in @ctx may
+ * point to different memory locations on return, so you must remember to reset
+ * any cached pointers from the @ctx, i.e. after the call to
+ * ntfs_map_runlist_nolock(), you will probably want to do:
+ * m = ctx->mrec;
+ * a = ctx->attr;
+ * Assuming you cache ctx->attr in a variable @a of type ATTR_RECORD * and that
+ * you cache ctx->mrec in a variable @m of type MFT_RECORD *.
+ *
+ * Return 0 on success and -errno on error. There is one special error code
+ * which is not an error as such. This is -ENOENT. It means that @vcn is out
+ * of bounds of the runlist.
+ *
+ * Note the runlist can be NULL after this function returns if @vcn is zero and
+ * the attribute has zero allocated size, i.e. there simply is no runlist.
+ *
+ * WARNING: If @ctx is supplied, regardless of whether success or failure is
+ * returned, you need to check IS_ERR(@ctx->mrec) and if TRUE the @ctx
+ * is no longer valid, i.e. you need to either call
+ * ntfs_attr_reinit_search_ctx() or ntfs_attr_put_search_ctx() on it.
+ * In that case PTR_ERR(@ctx->mrec) will give you the error code for
+ * why the mapping of the old inode failed.
+ *
+ * Locking: - The runlist described by @ni must be locked for writing on entry
+ * and is locked on return. Note the runlist will be modified.
+ * - If @ctx is NULL, the base mft record of @ni must not be mapped on
+ * entry and it will be left unmapped on return.
+ * - If @ctx is not NULL, the base mft record must be mapped on entry
+ * and it will be left mapped on return.
*/
-int ntfs_map_runlist(ntfs_inode *ni, VCN vcn)
+int ntfs_map_runlist_nolock(ntfs_inode *ni, VCN vcn, ntfs_attr_search_ctx *ctx)
{
+ VCN end_vcn;
+ unsigned long flags;
ntfs_inode *base_ni;
- ntfs_attr_search_ctx *ctx;
- MFT_RECORD *mrec;
+ MFT_RECORD *m;
+ ATTR_RECORD *a;
+ runlist_element *rl;
+ struct page *put_this_page = NULL;
int err = 0;
+ BOOL ctx_is_temporary, ctx_needs_reset;
+ ntfs_attr_search_ctx old_ctx = { NULL, };
ntfs_debug("Mapping runlist part containing vcn 0x%llx.",
(unsigned long long)vcn);
-
if (!NInoAttr(ni))
base_ni = ni;
else
base_ni = ni->ext.base_ntfs_ino;
+ if (!ctx) {
+ ctx_is_temporary = ctx_needs_reset = TRUE;
+ m = map_mft_record(base_ni);
+ if (IS_ERR(m))
+ return PTR_ERR(m);
+ ctx = ntfs_attr_get_search_ctx(base_ni, m);
+ if (unlikely(!ctx)) {
+ err = -ENOMEM;
+ goto err_out;
+ }
+ } else {
+ VCN allocated_size_vcn;
- mrec = map_mft_record(base_ni);
- if (IS_ERR(mrec))
- return PTR_ERR(mrec);
- ctx = ntfs_attr_get_search_ctx(base_ni, mrec);
- if (unlikely(!ctx)) {
- err = -ENOMEM;
+ BUG_ON(IS_ERR(ctx->mrec));
+ a = ctx->attr;
+ BUG_ON(!a->non_resident);
+ ctx_is_temporary = FALSE;
+ end_vcn = sle64_to_cpu(a->data.non_resident.highest_vcn);
+ read_lock_irqsave(&ni->size_lock, flags);
+ allocated_size_vcn = ni->allocated_size >>
+ ni->vol->cluster_size_bits;
+ read_unlock_irqrestore(&ni->size_lock, flags);
+ if (!a->data.non_resident.lowest_vcn && end_vcn <= 0)
+ end_vcn = allocated_size_vcn - 1;
+ /*
+ * If we already have the attribute extent containing @vcn in
+ * @ctx, no need to look it up again. We slightly cheat in
+ * that if vcn exceeds the allocated size, we will refuse to
+ * map the runlist below, so there is definitely no need to get
+ * the right attribute extent.
+ */
+ if (vcn >= allocated_size_vcn || (a->type == ni->type &&
+ a->name_length == ni->name_len &&
+ !memcmp((u8*)a + le16_to_cpu(a->name_offset),
+ ni->name, ni->name_len) &&
+ sle64_to_cpu(a->data.non_resident.lowest_vcn)
+ <= vcn && end_vcn >= vcn))
+ ctx_needs_reset = FALSE;
+ else {
+ /* Save the old search context. */
+ old_ctx = *ctx;
+ /*
+ * If the currently mapped (extent) inode is not the
+ * base inode we will unmap it when we reinitialize the
+ * search context which means we need to get a
+ * reference to the page containing the mapped mft
+ * record so we do not accidentally drop changes to the
+ * mft record when it has not been marked dirty yet.
+ */
+ if (old_ctx.base_ntfs_ino && old_ctx.ntfs_ino !=
+ old_ctx.base_ntfs_ino) {
+ put_this_page = old_ctx.ntfs_ino->page;
+ page_cache_get(put_this_page);
+ }
+ /*
+ * Reinitialize the search context so we can lookup the
+ * needed attribute extent.
+ */
+ ntfs_attr_reinit_search_ctx(ctx);
+ ctx_needs_reset = TRUE;
+ }
+ }
+ if (ctx_needs_reset) {
+ err = ntfs_attr_lookup(ni->type, ni->name, ni->name_len,
+ CASE_SENSITIVE, vcn, NULL, 0, ctx);
+ if (unlikely(err)) {
+ if (err == -ENOENT)
+ err = -EIO;
+ goto err_out;
+ }
+ BUG_ON(!ctx->attr->non_resident);
+ }
+ a = ctx->attr;
+ /*
+ * Only decompress the mapping pairs if @vcn is inside it. Otherwise
+ * we get into problems when we try to map an out of bounds vcn because
+ * we then try to map the already mapped runlist fragment and
+ * ntfs_mapping_pairs_decompress() fails.
+ */
+ end_vcn = sle64_to_cpu(a->data.non_resident.highest_vcn) + 1;
+ if (!a->data.non_resident.lowest_vcn && end_vcn == 1)
+ end_vcn = sle64_to_cpu(a->data.non_resident.allocated_size) >>
+ ni->vol->cluster_size_bits;
+ if (unlikely(vcn >= end_vcn)) {
+ err = -ENOENT;
goto err_out;
}
- err = ntfs_attr_lookup(ni->type, ni->name, ni->name_len,
- CASE_SENSITIVE, vcn, NULL, 0, ctx);
- if (unlikely(err))
- goto put_err_out;
+ rl = ntfs_mapping_pairs_decompress(ni->vol, a, ni->runlist.rl);
+ if (IS_ERR(rl))
+ err = PTR_ERR(rl);
+ else
+ ni->runlist.rl = rl;
+err_out:
+ if (ctx_is_temporary) {
+ if (likely(ctx))
+ ntfs_attr_put_search_ctx(ctx);
+ unmap_mft_record(base_ni);
+ } else if (ctx_needs_reset) {
+ /*
+ * If there is no attribute list, restoring the search context
+ * is acomplished simply by copying the saved context back over
+ * the caller supplied context. If there is an attribute list,
+ * things are more complicated as we need to deal with mapping
+ * of mft records and resulting potential changes in pointers.
+ */
+ if (NInoAttrList(base_ni)) {
+ /*
+ * If the currently mapped (extent) inode is not the
+ * one we had before, we need to unmap it and map the
+ * old one.
+ */
+ if (ctx->ntfs_ino != old_ctx.ntfs_ino) {
+ /*
+ * If the currently mapped inode is not the
+ * base inode, unmap it.
+ */
+ if (ctx->base_ntfs_ino && ctx->ntfs_ino !=
+ ctx->base_ntfs_ino) {
+ unmap_extent_mft_record(ctx->ntfs_ino);
+ ctx->mrec = ctx->base_mrec;
+ BUG_ON(!ctx->mrec);
+ }
+ /*
+ * If the old mapped inode is not the base
+ * inode, map it.
+ */
+ if (old_ctx.base_ntfs_ino &&
+ old_ctx.ntfs_ino !=
+ old_ctx.base_ntfs_ino) {
+retry_map:
+ ctx->mrec = map_mft_record(
+ old_ctx.ntfs_ino);
+ /*
+ * Something bad has happened. If out
+ * of memory retry till it succeeds.
+ * Any other errors are fatal and we
+ * return the error code in ctx->mrec.
+ * Let the caller deal with it... We
+ * just need to fudge things so the
+ * caller can reinit and/or put the
+ * search context safely.
+ */
+ if (IS_ERR(ctx->mrec)) {
+ if (PTR_ERR(ctx->mrec) ==
+ -ENOMEM) {
+ schedule();
+ goto retry_map;
+ } else
+ old_ctx.ntfs_ino =
+ old_ctx.
+ base_ntfs_ino;
+ }
+ }
+ }
+ /* Update the changed pointers in the saved context. */
+ if (ctx->mrec != old_ctx.mrec) {
+ if (!IS_ERR(ctx->mrec))
+ old_ctx.attr = (ATTR_RECORD*)(
+ (u8*)ctx->mrec +
+ ((u8*)old_ctx.attr -
+ (u8*)old_ctx.mrec));
+ old_ctx.mrec = ctx->mrec;
+ }
+ }
+ /* Restore the search context to the saved one. */
+ *ctx = old_ctx;
+ /*
+ * We drop the reference on the page we took earlier. In the
+ * case that IS_ERR(ctx->mrec) is true this means we might lose
+ * some changes to the mft record that had been made between
+ * the last time it was marked dirty/written out and now. This
+ * at this stage is not a problem as the mapping error is fatal
+ * enough that the mft record cannot be written out anyway and
+ * the caller is very likely to shutdown the whole inode
+ * immediately and mark the volume dirty for chkdsk to pick up
+ * the pieces anyway.
+ */
+ if (put_this_page)
+ page_cache_release(put_this_page);
+ }
+ return err;
+}
+
+/**
+ * ntfs_map_runlist - map (a part of) a runlist of an ntfs inode
+ * @ni: ntfs inode for which to map (part of) a runlist
+ * @vcn: map runlist part containing this vcn
+ *
+ * Map the part of a runlist containing the @vcn of the ntfs inode @ni.
+ *
+ * Return 0 on success and -errno on error. There is one special error code
+ * which is not an error as such. This is -ENOENT. It means that @vcn is out
+ * of bounds of the runlist.
+ *
+ * Locking: - The runlist must be unlocked on entry and is unlocked on return.
+ * - This function takes the runlist lock for writing and may modify
+ * the runlist.
+ */
+int ntfs_map_runlist(ntfs_inode *ni, VCN vcn)
+{
+ int err = 0;
down_write(&ni->runlist.lock);
/* Make sure someone else didn't do the work while we were sleeping. */
if (likely(ntfs_rl_vcn_to_lcn(ni->runlist.rl, vcn) <=
- LCN_RL_NOT_MAPPED)) {
- runlist_element *rl;
+ LCN_RL_NOT_MAPPED))
+ err = ntfs_map_runlist_nolock(ni, vcn, NULL);
+ up_write(&ni->runlist.lock);
+ return err;
+}
- rl = ntfs_mapping_pairs_decompress(ni->vol, ctx->attr,
- ni->runlist.rl);
- if (IS_ERR(rl))
- err = PTR_ERR(rl);
- else
- ni->runlist.rl = rl;
+/**
+ * ntfs_attr_vcn_to_lcn_nolock - convert a vcn into a lcn given an ntfs inode
+ * @ni: ntfs inode of the attribute whose runlist to search
+ * @vcn: vcn to convert
+ * @write_locked: true if the runlist is locked for writing
+ *
+ * Find the virtual cluster number @vcn in the runlist of the ntfs attribute
+ * described by the ntfs inode @ni and return the corresponding logical cluster
+ * number (lcn).
+ *
+ * If the @vcn is not mapped yet, the attempt is made to map the attribute
+ * extent containing the @vcn and the vcn to lcn conversion is retried.
+ *
+ * If @write_locked is true the caller has locked the runlist for writing and
+ * if false for reading.
+ *
+ * Since lcns must be >= 0, we use negative return codes with special meaning:
+ *
+ * Return code Meaning / Description
+ * ==========================================
+ * LCN_HOLE Hole / not allocated on disk.
+ * LCN_ENOENT There is no such vcn in the runlist, i.e. @vcn is out of bounds.
+ * LCN_ENOMEM Not enough memory to map runlist.
+ * LCN_EIO Critical error (runlist/file is corrupt, i/o error, etc).
+ *
+ * Locking: - The runlist must be locked on entry and is left locked on return.
+ * - If @write_locked is FALSE, i.e. the runlist is locked for reading,
+ * the lock may be dropped inside the function so you cannot rely on
+ * the runlist still being the same when this function returns.
+ */
+LCN ntfs_attr_vcn_to_lcn_nolock(ntfs_inode *ni, const VCN vcn,
+ const BOOL write_locked)
+{
+ LCN lcn;
+ unsigned long flags;
+ BOOL is_retry = FALSE;
+
+ ntfs_debug("Entering for i_ino 0x%lx, vcn 0x%llx, %s_locked.",
+ ni->mft_no, (unsigned long long)vcn,
+ write_locked ? "write" : "read");
+ BUG_ON(!ni);
+ BUG_ON(!NInoNonResident(ni));
+ BUG_ON(vcn < 0);
+ if (!ni->runlist.rl) {
+ read_lock_irqsave(&ni->size_lock, flags);
+ if (!ni->allocated_size) {
+ read_unlock_irqrestore(&ni->size_lock, flags);
+ return LCN_ENOENT;
+ }
+ read_unlock_irqrestore(&ni->size_lock, flags);
}
- up_write(&ni->runlist.lock);
+retry_remap:
+ /* Convert vcn to lcn. If that fails map the runlist and retry once. */
+ lcn = ntfs_rl_vcn_to_lcn(ni->runlist.rl, vcn);
+ if (likely(lcn >= LCN_HOLE)) {
+ ntfs_debug("Done, lcn 0x%llx.", (long long)lcn);
+ return lcn;
+ }
+ if (lcn != LCN_RL_NOT_MAPPED) {
+ if (lcn != LCN_ENOENT)
+ lcn = LCN_EIO;
+ } else if (!is_retry) {
+ int err;
-put_err_out:
- ntfs_attr_put_search_ctx(ctx);
-err_out:
- unmap_mft_record(base_ni);
- return err;
+ if (!write_locked) {
+ up_read(&ni->runlist.lock);
+ down_write(&ni->runlist.lock);
+ if (unlikely(ntfs_rl_vcn_to_lcn(ni->runlist.rl, vcn) !=
+ LCN_RL_NOT_MAPPED)) {
+ up_write(&ni->runlist.lock);
+ down_read(&ni->runlist.lock);
+ goto retry_remap;
+ }
+ }
+ err = ntfs_map_runlist_nolock(ni, vcn, NULL);
+ if (!write_locked) {
+ up_write(&ni->runlist.lock);
+ down_read(&ni->runlist.lock);
+ }
+ if (likely(!err)) {
+ is_retry = TRUE;
+ goto retry_remap;
+ }
+ if (err == -ENOENT)
+ lcn = LCN_ENOENT;
+ else if (err == -ENOMEM)
+ lcn = LCN_ENOMEM;
+ else
+ lcn = LCN_EIO;
+ }
+ if (lcn != LCN_ENOENT)
+ ntfs_error(ni->vol->sb, "Failed with error code %lli.",
+ (long long)lcn);
+ return lcn;
}
/**
- * ntfs_find_vcn - find a vcn in the runlist described by an ntfs inode
+ * ntfs_attr_find_vcn_nolock - find a vcn in the runlist of an ntfs inode
* @ni: ntfs inode describing the runlist to search
* @vcn: vcn to find
- * @need_write: if false, lock for reading and if true, lock for writing
+ * @ctx: active attribute search context if present or NULL if not
*
* Find the virtual cluster number @vcn in the runlist described by the ntfs
* inode @ni and return the address of the runlist element containing the @vcn.
- * The runlist is left locked and the caller has to unlock it. If @need_write
- * is true, the runlist is locked for writing and if @need_write is false, the
- * runlist is locked for reading. In the error case, the runlist is not left
- * locked.
*
+ * If the @vcn is not mapped yet, the attempt is made to map the attribute
+ * extent containing the @vcn and the vcn to lcn conversion is retried.
+ *
+ * If @ctx is specified, it is an active search context of @ni and its base mft
+ * record. This is needed when ntfs_attr_find_vcn_nolock() encounters unmapped
+ * runlist fragments and allows their mapping. If you do not have the mft
+ * record mapped, you can specify @ctx as NULL and ntfs_attr_find_vcn_nolock()
+ * will perform the necessary mapping and unmapping.
+ *
+ * Note, ntfs_attr_find_vcn_nolock() saves the state of @ctx on entry and
+ * restores it before returning. Thus, @ctx will be left pointing to the same
+ * attribute on return as on entry. However, the actual pointers in @ctx may
+ * point to different memory locations on return, so you must remember to reset
+ * any cached pointers from the @ctx, i.e. after the call to
+ * ntfs_attr_find_vcn_nolock(), you will probably want to do:
+ * m = ctx->mrec;
+ * a = ctx->attr;
+ * Assuming you cache ctx->attr in a variable @a of type ATTR_RECORD * and that
+ * you cache ctx->mrec in a variable @m of type MFT_RECORD *.
* Note you need to distinguish between the lcn of the returned runlist element
* being >= 0 and LCN_HOLE. In the later case you have to return zeroes on
* read and allocate clusters on write.
* -ENOMEM - Not enough memory to map runlist.
* -EIO - Critical error (runlist/file is corrupt, i/o error, etc).
*
- * Locking: - The runlist must be unlocked on entry.
- * - On failing return, the runlist is unlocked.
- * - On successful return, the runlist is locked. If @need_write us
- * true, it is locked for writing. Otherwise is is locked for
- * reading.
+ * WARNING: If @ctx is supplied, regardless of whether success or failure is
+ * returned, you need to check IS_ERR(@ctx->mrec) and if TRUE the @ctx
+ * is no longer valid, i.e. you need to either call
+ * ntfs_attr_reinit_search_ctx() or ntfs_attr_put_search_ctx() on it.
+ * In that case PTR_ERR(@ctx->mrec) will give you the error code for
+ * why the mapping of the old inode failed.
+ *
+ * Locking: - The runlist described by @ni must be locked for writing on entry
+ * and is locked on return. Note the runlist may be modified when
+ * needed runlist fragments need to be mapped.
+ * - If @ctx is NULL, the base mft record of @ni must not be mapped on
+ * entry and it will be left unmapped on return.
+ * - If @ctx is not NULL, the base mft record must be mapped on entry
+ * and it will be left mapped on return.
*/
-runlist_element *ntfs_find_vcn(ntfs_inode *ni, const VCN vcn,
- const BOOL need_write)
+runlist_element *ntfs_attr_find_vcn_nolock(ntfs_inode *ni, const VCN vcn,
+ ntfs_attr_search_ctx *ctx)
{
+ unsigned long flags;
runlist_element *rl;
int err = 0;
BOOL is_retry = FALSE;
- ntfs_debug("Entering for i_ino 0x%lx, vcn 0x%llx, lock for %sing.",
- ni->mft_no, (unsigned long long)vcn,
- !need_write ? "read" : "writ");
+ ntfs_debug("Entering for i_ino 0x%lx, vcn 0x%llx, with%s ctx.",
+ ni->mft_no, (unsigned long long)vcn, ctx ? "" : "out");
BUG_ON(!ni);
BUG_ON(!NInoNonResident(ni));
BUG_ON(vcn < 0);
-lock_retry_remap:
- if (!need_write)
- down_read(&ni->runlist.lock);
- else
- down_write(&ni->runlist.lock);
+ if (!ni->runlist.rl) {
+ read_lock_irqsave(&ni->size_lock, flags);
+ if (!ni->allocated_size) {
+ read_unlock_irqrestore(&ni->size_lock, flags);
+ return ERR_PTR(-ENOENT);
+ }
+ read_unlock_irqrestore(&ni->size_lock, flags);
+ }
+retry_remap:
rl = ni->runlist.rl;
if (likely(rl && vcn >= rl[0].vcn)) {
while (likely(rl->length)) {
- if (likely(vcn < rl[1].vcn)) {
+ if (unlikely(vcn < rl[1].vcn)) {
if (likely(rl->lcn >= LCN_HOLE)) {
ntfs_debug("Done.");
return rl;
err = -EIO;
}
}
- if (!need_write)
- up_read(&ni->runlist.lock);
- else
- up_write(&ni->runlist.lock);
if (!err && !is_retry) {
/*
- * The @vcn is in an unmapped region, map the runlist and
- * retry.
+ * If the search context is invalid we cannot map the unmapped
+ * region.
*/
- err = ntfs_map_runlist(ni, vcn);
- if (likely(!err)) {
- is_retry = TRUE;
- goto lock_retry_remap;
+ if (IS_ERR(ctx->mrec))
+ err = PTR_ERR(ctx->mrec);
+ else {
+ /*
+ * The @vcn is in an unmapped region, map the runlist
+ * and retry.
+ */
+ err = ntfs_map_runlist_nolock(ni, vcn, ctx);
+ if (likely(!err)) {
+ is_retry = TRUE;
+ goto retry_remap;
+ }
}
- /*
- * -EINVAL and -ENOENT coming from a failed mapping attempt are
- * equivalent to i/o errors for us as they should not happen in
- * our code paths.
- */
- if (err == -EINVAL || err == -ENOENT)
+ if (err == -EINVAL)
err = -EIO;
} else if (!err)
err = -EIO;
- ntfs_error(ni->vol->sb, "Failed with error code %i.", err);
+ if (err != -ENOENT)
+ ntfs_error(ni->vol->sb, "Failed with error code %i.", err);
return ERR_PTR(err);
}
block_size_bits = sb->s_blocksize_bits;
down_read(&runlist->lock);
rl = runlist->rl;
+ if (!rl) {
+ ntfs_error(sb, "Cannot read attribute list since runlist is "
+ "missing.");
+ goto err_out;
+ }
/* Read all clusters specified by the runlist one run at a time. */
while (rl->length) {
lcn = ntfs_rl_vcn_to_lcn(rl, rl->vcn);
le32_to_cpu(ctx->mrec->bytes_allocated))
break;
if (a->type == AT_END)
- continue;
+ break;
if (!a->length)
break;
if (al_entry->instance != a->instance)
ntfs_inode *base_ni;
ntfs_debug("Entering.");
+ BUG_ON(IS_ERR(ctx->mrec));
if (ctx->base_ntfs_ino)
base_ni = ctx->base_ntfs_ino;
else
static inline void ntfs_attr_init_search_ctx(ntfs_attr_search_ctx *ctx,
ntfs_inode *ni, MFT_RECORD *mrec)
{
- ctx->mrec = mrec;
- /* Sanity checks are performed elsewhere. */
- ctx->attr = (ATTR_RECORD*)((u8*)mrec + le16_to_cpu(mrec->attrs_offset));
- ctx->is_first = TRUE;
- ctx->ntfs_ino = ni;
- ctx->al_entry = NULL;
- ctx->base_ntfs_ino = NULL;
- ctx->base_mrec = NULL;
- ctx->base_attr = NULL;
+ *ctx = (ntfs_attr_search_ctx) {
+ .mrec = mrec,
+ /* Sanity checks are performed elsewhere. */
+ .attr = (ATTR_RECORD*)((u8*)mrec +
+ le16_to_cpu(mrec->attrs_offset)),
+ .is_first = TRUE,
+ .ntfs_ino = ni,
+ };
}
/**
return;
}
+#ifdef NTFS_RW
+
/**
* ntfs_attr_find_in_attrdef - find an attribute in the $AttrDef system file
* @vol: ntfs volume to which the attribute belongs
* Check whether the attribute of @type on the ntfs volume @vol is allowed to
* be non-resident. This information is obtained from $AttrDef system file.
*
- * Return 0 if the attribute is allowed to be non-resident, -EPERM if not, or
+ * Return 0 if the attribute is allowed to be non-resident, -EPERM if not, and
* -ENOENT if the attribute is not listed in $AttrDef.
*/
int ntfs_attr_can_be_non_resident(const ntfs_volume *vol, const ATTR_TYPE type)
{
ATTR_DEF *ad;
- /*
- * $DATA is always allowed to be non-resident even if $AttrDef does not
- * specify this in the flags of the $DATA attribute definition record.
- */
- if (type == AT_DATA)
- return 0;
/* Find the attribute definition record in $AttrDef. */
ad = ntfs_attr_find_in_attrdef(vol, type);
if (unlikely(!ad))
return -ENOENT;
/* Check the flags and return the result. */
- if (ad->flags & CAN_BE_NON_RESIDENT)
- return 0;
- return -EPERM;
+ if (ad->flags & ATTR_DEF_RESIDENT)
+ return -EPERM;
+ return 0;
}
/**
*/
int ntfs_attr_can_be_resident(const ntfs_volume *vol, const ATTR_TYPE type)
{
- if (type != AT_INDEX_ALLOCATION && type != AT_EA)
- return 0;
- return -EPERM;
+ if (type == AT_INDEX_ALLOCATION)
+ return -EPERM;
+ return 0;
}
/**
return 0;
}
+/**
+ * ntfs_resident_attr_value_resize - resize the value of a resident attribute
+ * @m: mft record containing attribute record
+ * @a: attribute record whose value to resize
+ * @new_size: new size in bytes to which to resize the attribute value of @a
+ *
+ * Resize the value of the attribute @a in the mft record @m to @new_size bytes.
+ * If the value is made bigger, the newly allocated space is cleared.
+ *
+ * Return 0 on success and -errno on error. The following error codes are
+ * defined:
+ * -ENOSPC - Not enough space in the mft record @m to perform the resize.
+ *
+ * Note: On error, no modifications have been performed whatsoever.
+ *
+ * Warning: If you make a record smaller without having copied all the data you
+ * are interested in the data may be overwritten.
+ */
+int ntfs_resident_attr_value_resize(MFT_RECORD *m, ATTR_RECORD *a,
+ const u32 new_size)
+{
+ u32 old_size;
+
+ /* Resize the resident part of the attribute record. */
+ if (ntfs_attr_record_resize(m, a,
+ le16_to_cpu(a->data.resident.value_offset) + new_size))
+ return -ENOSPC;
+ /*
+ * The resize succeeded! If we made the attribute value bigger, clear
+ * the area between the old size and @new_size.
+ */
+ old_size = le32_to_cpu(a->data.resident.value_length);
+ if (new_size > old_size)
+ memset((u8*)a + le16_to_cpu(a->data.resident.value_offset) +
+ old_size, 0, new_size - old_size);
+ /* Finally update the length of the attribute value. */
+ a->data.resident.value_length = cpu_to_le32(new_size);
+ return 0;
+}
+
+/**
+ * ntfs_attr_make_non_resident - convert a resident to a non-resident attribute
+ * @ni: ntfs inode describing the attribute to convert
+ * @data_size: size of the resident data to copy to the non-resident attribute
+ *
+ * Convert the resident ntfs attribute described by the ntfs inode @ni to a
+ * non-resident one.
+ *
+ * @data_size must be equal to the attribute value size. This is needed since
+ * we need to know the size before we can map the mft record and our callers
+ * always know it. The reason we cannot simply read the size from the vfs
+ * inode i_size is that this is not necessarily uptodate. This happens when
+ * ntfs_attr_make_non_resident() is called in the ->truncate call path(s).
+ *
+ * Return 0 on success and -errno on error. The following error return codes
+ * are defined:
+ * -EPERM - The attribute is not allowed to be non-resident.
+ * -ENOMEM - Not enough memory.
+ * -ENOSPC - Not enough disk space.
+ * -EINVAL - Attribute not defined on the volume.
+ * -EIO - I/o error or other error.
+ * Note that -ENOSPC is also returned in the case that there is not enough
+ * space in the mft record to do the conversion. This can happen when the mft
+ * record is already very full. The caller is responsible for trying to make
+ * space in the mft record and trying again. FIXME: Do we need a separate
+ * error return code for this kind of -ENOSPC or is it always worth trying
+ * again in case the attribute may then fit in a resident state so no need to
+ * make it non-resident at all? Ho-hum... (AIA)
+ *
+ * NOTE to self: No changes in the attribute list are required to move from
+ * a resident to a non-resident attribute.
+ *
+ * Locking: - The caller must hold i_mutex on the inode.
+ */
+int ntfs_attr_make_non_resident(ntfs_inode *ni, const u32 data_size)
+{
+ s64 new_size;
+ struct inode *vi = VFS_I(ni);
+ ntfs_volume *vol = ni->vol;
+ ntfs_inode *base_ni;
+ MFT_RECORD *m;
+ ATTR_RECORD *a;
+ ntfs_attr_search_ctx *ctx;
+ struct page *page;
+ runlist_element *rl;
+ u8 *kaddr;
+ unsigned long flags;
+ int mp_size, mp_ofs, name_ofs, arec_size, err, err2;
+ u32 attr_size;
+ u8 old_res_attr_flags;
+
+ /* Check that the attribute is allowed to be non-resident. */
+ err = ntfs_attr_can_be_non_resident(vol, ni->type);
+ if (unlikely(err)) {
+ if (err == -EPERM)
+ ntfs_debug("Attribute is not allowed to be "
+ "non-resident.");
+ else
+ ntfs_debug("Attribute not defined on the NTFS "
+ "volume!");
+ return err;
+ }
+ /*
+ * FIXME: Compressed and encrypted attributes are not supported when
+ * writing and we should never have gotten here for them.
+ */
+ BUG_ON(NInoCompressed(ni));
+ BUG_ON(NInoEncrypted(ni));
+ /*
+ * The size needs to be aligned to a cluster boundary for allocation
+ * purposes.
+ */
+ new_size = (data_size + vol->cluster_size - 1) &
+ ~(vol->cluster_size - 1);
+ if (new_size > 0) {
+ /*
+ * Will need the page later and since the page lock nests
+ * outside all ntfs locks, we need to get the page now.
+ */
+ page = find_or_create_page(vi->i_mapping, 0,
+ mapping_gfp_mask(vi->i_mapping));
+ if (unlikely(!page))
+ return -ENOMEM;
+ /* Start by allocating clusters to hold the attribute value. */
+ rl = ntfs_cluster_alloc(vol, 0, new_size >>
+ vol->cluster_size_bits, -1, DATA_ZONE, TRUE);
+ if (IS_ERR(rl)) {
+ err = PTR_ERR(rl);
+ ntfs_debug("Failed to allocate cluster%s, error code "
+ "%i.", (new_size >>
+ vol->cluster_size_bits) > 1 ? "s" : "",
+ err);
+ goto page_err_out;
+ }
+ } else {
+ rl = NULL;
+ page = NULL;
+ }
+ /* Determine the size of the mapping pairs array. */
+ mp_size = ntfs_get_size_for_mapping_pairs(vol, rl, 0, -1);
+ if (unlikely(mp_size < 0)) {
+ err = mp_size;
+ ntfs_debug("Failed to get size for mapping pairs array, error "
+ "code %i.", err);
+ goto rl_err_out;
+ }
+ down_write(&ni->runlist.lock);
+ if (!NInoAttr(ni))
+ base_ni = ni;
+ else
+ base_ni = ni->ext.base_ntfs_ino;
+ m = map_mft_record(base_ni);
+ if (IS_ERR(m)) {
+ err = PTR_ERR(m);
+ m = NULL;
+ ctx = NULL;
+ goto err_out;
+ }
+ ctx = ntfs_attr_get_search_ctx(base_ni, m);
+ if (unlikely(!ctx)) {
+ err = -ENOMEM;
+ goto err_out;
+ }
+ err = ntfs_attr_lookup(ni->type, ni->name, ni->name_len,
+ CASE_SENSITIVE, 0, NULL, 0, ctx);
+ if (unlikely(err)) {
+ if (err == -ENOENT)
+ err = -EIO;
+ goto err_out;
+ }
+ m = ctx->mrec;
+ a = ctx->attr;
+ BUG_ON(NInoNonResident(ni));
+ BUG_ON(a->non_resident);
+ /*
+ * Calculate new offsets for the name and the mapping pairs array.
+ */
+ if (NInoSparse(ni) || NInoCompressed(ni))
+ name_ofs = (offsetof(ATTR_REC,
+ data.non_resident.compressed_size) +
+ sizeof(a->data.non_resident.compressed_size) +
+ 7) & ~7;
+ else
+ name_ofs = (offsetof(ATTR_REC,
+ data.non_resident.compressed_size) + 7) & ~7;
+ mp_ofs = (name_ofs + a->name_length * sizeof(ntfschar) + 7) & ~7;
+ /*
+ * Determine the size of the resident part of the now non-resident
+ * attribute record.
+ */
+ arec_size = (mp_ofs + mp_size + 7) & ~7;
+ /*
+ * If the page is not uptodate bring it uptodate by copying from the
+ * attribute value.
+ */
+ attr_size = le32_to_cpu(a->data.resident.value_length);
+ BUG_ON(attr_size != data_size);
+ if (page && !PageUptodate(page)) {
+ kaddr = kmap_atomic(page, KM_USER0);
+ memcpy(kaddr, (u8*)a +
+ le16_to_cpu(a->data.resident.value_offset),
+ attr_size);
+ memset(kaddr + attr_size, 0, PAGE_CACHE_SIZE - attr_size);
+ kunmap_atomic(kaddr, KM_USER0);
+ flush_dcache_page(page);
+ SetPageUptodate(page);
+ }
+ /* Backup the attribute flag. */
+ old_res_attr_flags = a->data.resident.flags;
+ /* Resize the resident part of the attribute record. */
+ err = ntfs_attr_record_resize(m, a, arec_size);
+ if (unlikely(err))
+ goto err_out;
+ /*
+ * Convert the resident part of the attribute record to describe a
+ * non-resident attribute.
+ */
+ a->non_resident = 1;
+ /* Move the attribute name if it exists and update the offset. */
+ if (a->name_length)
+ memmove((u8*)a + name_ofs, (u8*)a + le16_to_cpu(a->name_offset),
+ a->name_length * sizeof(ntfschar));
+ a->name_offset = cpu_to_le16(name_ofs);
+ /* Setup the fields specific to non-resident attributes. */
+ a->data.non_resident.lowest_vcn = 0;
+ a->data.non_resident.highest_vcn = cpu_to_sle64((new_size - 1) >>
+ vol->cluster_size_bits);
+ a->data.non_resident.mapping_pairs_offset = cpu_to_le16(mp_ofs);
+ memset(&a->data.non_resident.reserved, 0,
+ sizeof(a->data.non_resident.reserved));
+ a->data.non_resident.allocated_size = cpu_to_sle64(new_size);
+ a->data.non_resident.data_size =
+ a->data.non_resident.initialized_size =
+ cpu_to_sle64(attr_size);
+ if (NInoSparse(ni) || NInoCompressed(ni)) {
+ a->data.non_resident.compression_unit = 0;
+ if (NInoCompressed(ni) || vol->major_ver < 3)
+ a->data.non_resident.compression_unit = 4;
+ a->data.non_resident.compressed_size =
+ a->data.non_resident.allocated_size;
+ } else
+ a->data.non_resident.compression_unit = 0;
+ /* Generate the mapping pairs array into the attribute record. */
+ err = ntfs_mapping_pairs_build(vol, (u8*)a + mp_ofs,
+ arec_size - mp_ofs, rl, 0, -1, NULL);
+ if (unlikely(err)) {
+ ntfs_debug("Failed to build mapping pairs, error code %i.",
+ err);
+ goto undo_err_out;
+ }
+ /* Setup the in-memory attribute structure to be non-resident. */
+ ni->runlist.rl = rl;
+ write_lock_irqsave(&ni->size_lock, flags);
+ ni->allocated_size = new_size;
+ if (NInoSparse(ni) || NInoCompressed(ni)) {
+ ni->itype.compressed.size = ni->allocated_size;
+ if (a->data.non_resident.compression_unit) {
+ ni->itype.compressed.block_size = 1U << (a->data.
+ non_resident.compression_unit +
+ vol->cluster_size_bits);
+ ni->itype.compressed.block_size_bits =
+ ffs(ni->itype.compressed.block_size) -
+ 1;
+ ni->itype.compressed.block_clusters = 1U <<
+ a->data.non_resident.compression_unit;
+ } else {
+ ni->itype.compressed.block_size = 0;
+ ni->itype.compressed.block_size_bits = 0;
+ ni->itype.compressed.block_clusters = 0;
+ }
+ vi->i_blocks = ni->itype.compressed.size >> 9;
+ } else
+ vi->i_blocks = ni->allocated_size >> 9;
+ write_unlock_irqrestore(&ni->size_lock, flags);
+ /*
+ * This needs to be last since the address space operations ->readpage
+ * and ->writepage can run concurrently with us as they are not
+ * serialized on i_mutex. Note, we are not allowed to fail once we flip
+ * this switch, which is another reason to do this last.
+ */
+ NInoSetNonResident(ni);
+ /* Mark the mft record dirty, so it gets written back. */
+ flush_dcache_mft_record_page(ctx->ntfs_ino);
+ mark_mft_record_dirty(ctx->ntfs_ino);
+ ntfs_attr_put_search_ctx(ctx);
+ unmap_mft_record(base_ni);
+ up_write(&ni->runlist.lock);
+ if (page) {
+ set_page_dirty(page);
+ unlock_page(page);
+ mark_page_accessed(page);
+ page_cache_release(page);
+ }
+ ntfs_debug("Done.");
+ return 0;
+undo_err_out:
+ /* Convert the attribute back into a resident attribute. */
+ a->non_resident = 0;
+ /* Move the attribute name if it exists and update the offset. */
+ name_ofs = (offsetof(ATTR_RECORD, data.resident.reserved) +
+ sizeof(a->data.resident.reserved) + 7) & ~7;
+ if (a->name_length)
+ memmove((u8*)a + name_ofs, (u8*)a + le16_to_cpu(a->name_offset),
+ a->name_length * sizeof(ntfschar));
+ mp_ofs = (name_ofs + a->name_length * sizeof(ntfschar) + 7) & ~7;
+ a->name_offset = cpu_to_le16(name_ofs);
+ arec_size = (mp_ofs + attr_size + 7) & ~7;
+ /* Resize the resident part of the attribute record. */
+ err2 = ntfs_attr_record_resize(m, a, arec_size);
+ if (unlikely(err2)) {
+ /*
+ * This cannot happen (well if memory corruption is at work it
+ * could happen in theory), but deal with it as well as we can.
+ * If the old size is too small, truncate the attribute,
+ * otherwise simply give it a larger allocated size.
+ * FIXME: Should check whether chkdsk complains when the
+ * allocated size is much bigger than the resident value size.
+ */
+ arec_size = le32_to_cpu(a->length);
+ if ((mp_ofs + attr_size) > arec_size) {
+ err2 = attr_size;
+ attr_size = arec_size - mp_ofs;
+ ntfs_error(vol->sb, "Failed to undo partial resident "
+ "to non-resident attribute "
+ "conversion. Truncating inode 0x%lx, "
+ "attribute type 0x%x from %i bytes to "
+ "%i bytes to maintain metadata "
+ "consistency. THIS MEANS YOU ARE "
+ "LOSING %i BYTES DATA FROM THIS %s.",
+ vi->i_ino,
+ (unsigned)le32_to_cpu(ni->type),
+ err2, attr_size, err2 - attr_size,
+ ((ni->type == AT_DATA) &&
+ !ni->name_len) ? "FILE": "ATTRIBUTE");
+ write_lock_irqsave(&ni->size_lock, flags);
+ ni->initialized_size = attr_size;
+ i_size_write(vi, attr_size);
+ write_unlock_irqrestore(&ni->size_lock, flags);
+ }
+ }
+ /* Setup the fields specific to resident attributes. */
+ a->data.resident.value_length = cpu_to_le32(attr_size);
+ a->data.resident.value_offset = cpu_to_le16(mp_ofs);
+ a->data.resident.flags = old_res_attr_flags;
+ memset(&a->data.resident.reserved, 0,
+ sizeof(a->data.resident.reserved));
+ /* Copy the data from the page back to the attribute value. */
+ if (page) {
+ kaddr = kmap_atomic(page, KM_USER0);
+ memcpy((u8*)a + mp_ofs, kaddr, attr_size);
+ kunmap_atomic(kaddr, KM_USER0);
+ }
+ /* Setup the allocated size in the ntfs inode in case it changed. */
+ write_lock_irqsave(&ni->size_lock, flags);
+ ni->allocated_size = arec_size - mp_ofs;
+ write_unlock_irqrestore(&ni->size_lock, flags);
+ /* Mark the mft record dirty, so it gets written back. */
+ flush_dcache_mft_record_page(ctx->ntfs_ino);
+ mark_mft_record_dirty(ctx->ntfs_ino);
+err_out:
+ if (ctx)
+ ntfs_attr_put_search_ctx(ctx);
+ if (m)
+ unmap_mft_record(base_ni);
+ ni->runlist.rl = NULL;
+ up_write(&ni->runlist.lock);
+rl_err_out:
+ if (rl) {
+ if (ntfs_cluster_free_from_rl(vol, rl) < 0) {
+ ntfs_error(vol->sb, "Failed to release allocated "
+ "cluster(s) in error code path. Run "
+ "chkdsk to recover the lost "
+ "cluster(s).");
+ NVolSetErrors(vol);
+ }
+ ntfs_free(rl);
+page_err_out:
+ unlock_page(page);
+ page_cache_release(page);
+ }
+ if (err == -EINVAL)
+ err = -EIO;
+ return err;
+}
+
+/**
+ * ntfs_attr_extend_allocation - extend the allocated space of an attribute
+ * @ni: ntfs inode of the attribute whose allocation to extend
+ * @new_alloc_size: new size in bytes to which to extend the allocation to
+ * @new_data_size: new size in bytes to which to extend the data to
+ * @data_start: beginning of region which is required to be non-sparse
+ *
+ * Extend the allocated space of an attribute described by the ntfs inode @ni
+ * to @new_alloc_size bytes. If @data_start is -1, the whole extension may be
+ * implemented as a hole in the file (as long as both the volume and the ntfs
+ * inode @ni have sparse support enabled). If @data_start is >= 0, then the
+ * region between the old allocated size and @data_start - 1 may be made sparse
+ * but the regions between @data_start and @new_alloc_size must be backed by
+ * actual clusters.
+ *
+ * If @new_data_size is -1, it is ignored. If it is >= 0, then the data size
+ * of the attribute is extended to @new_data_size. Note that the i_size of the
+ * vfs inode is not updated. Only the data size in the base attribute record
+ * is updated. The caller has to update i_size separately if this is required.
+ * WARNING: It is a BUG() for @new_data_size to be smaller than the old data
+ * size as well as for @new_data_size to be greater than @new_alloc_size.
+ *
+ * For resident attributes this involves resizing the attribute record and if
+ * necessary moving it and/or other attributes into extent mft records and/or
+ * converting the attribute to a non-resident attribute which in turn involves
+ * extending the allocation of a non-resident attribute as described below.
+ *
+ * For non-resident attributes this involves allocating clusters in the data
+ * zone on the volume (except for regions that are being made sparse) and
+ * extending the run list to describe the allocated clusters as well as
+ * updating the mapping pairs array of the attribute. This in turn involves
+ * resizing the attribute record and if necessary moving it and/or other
+ * attributes into extent mft records and/or splitting the attribute record
+ * into multiple extent attribute records.
+ *
+ * Also, the attribute list attribute is updated if present and in some of the
+ * above cases (the ones where extent mft records/attributes come into play),
+ * an attribute list attribute is created if not already present.
+ *
+ * Return the new allocated size on success and -errno on error. In the case
+ * that an error is encountered but a partial extension at least up to
+ * @data_start (if present) is possible, the allocation is partially extended
+ * and this is returned. This means the caller must check the returned size to
+ * determine if the extension was partial. If @data_start is -1 then partial
+ * allocations are not performed.
+ *
+ * WARNING: Do not call ntfs_attr_extend_allocation() for $MFT/$DATA.
+ *
+ * Locking: This function takes the runlist lock of @ni for writing as well as
+ * locking the mft record of the base ntfs inode. These locks are maintained
+ * throughout execution of the function. These locks are required so that the
+ * attribute can be resized safely and so that it can for example be converted
+ * from resident to non-resident safely.
+ *
+ * TODO: At present attribute list attribute handling is not implemented.
+ *
+ * TODO: At present it is not safe to call this function for anything other
+ * than the $DATA attribute(s) of an uncompressed and unencrypted file.
+ */
+s64 ntfs_attr_extend_allocation(ntfs_inode *ni, s64 new_alloc_size,
+ const s64 new_data_size, const s64 data_start)
+{
+ VCN vcn;
+ s64 ll, allocated_size, start = data_start;
+ struct inode *vi = VFS_I(ni);
+ ntfs_volume *vol = ni->vol;
+ ntfs_inode *base_ni;
+ MFT_RECORD *m;
+ ATTR_RECORD *a;
+ ntfs_attr_search_ctx *ctx;
+ runlist_element *rl, *rl2;
+ unsigned long flags;
+ int err, mp_size;
+ u32 attr_len = 0; /* Silence stupid gcc warning. */
+ BOOL mp_rebuilt;
+
+#ifdef NTFS_DEBUG
+ read_lock_irqsave(&ni->size_lock, flags);
+ allocated_size = ni->allocated_size;
+ read_unlock_irqrestore(&ni->size_lock, flags);
+ ntfs_debug("Entering for i_ino 0x%lx, attribute type 0x%x, "
+ "old_allocated_size 0x%llx, "
+ "new_allocated_size 0x%llx, new_data_size 0x%llx, "
+ "data_start 0x%llx.", vi->i_ino,
+ (unsigned)le32_to_cpu(ni->type),
+ (unsigned long long)allocated_size,
+ (unsigned long long)new_alloc_size,
+ (unsigned long long)new_data_size,
+ (unsigned long long)start);
+#endif
+retry_extend:
+ /*
+ * For non-resident attributes, @start and @new_size need to be aligned
+ * to cluster boundaries for allocation purposes.
+ */
+ if (NInoNonResident(ni)) {
+ if (start > 0)
+ start &= ~(s64)vol->cluster_size_mask;
+ new_alloc_size = (new_alloc_size + vol->cluster_size - 1) &
+ ~(s64)vol->cluster_size_mask;
+ }
+ BUG_ON(new_data_size >= 0 && new_data_size > new_alloc_size);
+ /* Check if new size is allowed in $AttrDef. */
+ err = ntfs_attr_size_bounds_check(vol, ni->type, new_alloc_size);
+ if (unlikely(err)) {
+ /* Only emit errors when the write will fail completely. */
+ read_lock_irqsave(&ni->size_lock, flags);
+ allocated_size = ni->allocated_size;
+ read_unlock_irqrestore(&ni->size_lock, flags);
+ if (start < 0 || start >= allocated_size) {
+ if (err == -ERANGE) {
+ ntfs_error(vol->sb, "Cannot extend allocation "
+ "of inode 0x%lx, attribute "
+ "type 0x%x, because the new "
+ "allocation would exceed the "
+ "maximum allowed size for "
+ "this attribute type.",
+ vi->i_ino, (unsigned)
+ le32_to_cpu(ni->type));
+ } else {
+ ntfs_error(vol->sb, "Cannot extend allocation "
+ "of inode 0x%lx, attribute "
+ "type 0x%x, because this "
+ "attribute type is not "
+ "defined on the NTFS volume. "
+ "Possible corruption! You "
+ "should run chkdsk!",
+ vi->i_ino, (unsigned)
+ le32_to_cpu(ni->type));
+ }
+ }
+ /* Translate error code to be POSIX conformant for write(2). */
+ if (err == -ERANGE)
+ err = -EFBIG;
+ else
+ err = -EIO;
+ return err;
+ }
+ if (!NInoAttr(ni))
+ base_ni = ni;
+ else
+ base_ni = ni->ext.base_ntfs_ino;
+ /*
+ * We will be modifying both the runlist (if non-resident) and the mft
+ * record so lock them both down.
+ */
+ down_write(&ni->runlist.lock);
+ m = map_mft_record(base_ni);
+ if (IS_ERR(m)) {
+ err = PTR_ERR(m);
+ m = NULL;
+ ctx = NULL;
+ goto err_out;
+ }
+ ctx = ntfs_attr_get_search_ctx(base_ni, m);
+ if (unlikely(!ctx)) {
+ err = -ENOMEM;
+ goto err_out;
+ }
+ read_lock_irqsave(&ni->size_lock, flags);
+ allocated_size = ni->allocated_size;
+ read_unlock_irqrestore(&ni->size_lock, flags);
+ /*
+ * If non-resident, seek to the last extent. If resident, there is
+ * only one extent, so seek to that.
+ */
+ vcn = NInoNonResident(ni) ? allocated_size >> vol->cluster_size_bits :
+ 0;
+ /*
+ * Abort if someone did the work whilst we waited for the locks. If we
+ * just converted the attribute from resident to non-resident it is
+ * likely that exactly this has happened already. We cannot quite
+ * abort if we need to update the data size.
+ */
+ if (unlikely(new_alloc_size <= allocated_size)) {
+ ntfs_debug("Allocated size already exceeds requested size.");
+ new_alloc_size = allocated_size;
+ if (new_data_size < 0)
+ goto done;
+ /*
+ * We want the first attribute extent so that we can update the
+ * data size.
+ */
+ vcn = 0;
+ }
+ err = ntfs_attr_lookup(ni->type, ni->name, ni->name_len,
+ CASE_SENSITIVE, vcn, NULL, 0, ctx);
+ if (unlikely(err)) {
+ if (err == -ENOENT)
+ err = -EIO;
+ goto err_out;
+ }
+ m = ctx->mrec;
+ a = ctx->attr;
+ /* Use goto to reduce indentation. */
+ if (a->non_resident)
+ goto do_non_resident_extend;
+ BUG_ON(NInoNonResident(ni));
+ /* The total length of the attribute value. */
+ attr_len = le32_to_cpu(a->data.resident.value_length);
+ /*
+ * Extend the attribute record to be able to store the new attribute
+ * size. ntfs_attr_record_resize() will not do anything if the size is
+ * not changing.
+ */
+ if (new_alloc_size < vol->mft_record_size &&
+ !ntfs_attr_record_resize(m, a,
+ le16_to_cpu(a->data.resident.value_offset) +
+ new_alloc_size)) {
+ /* The resize succeeded! */
+ write_lock_irqsave(&ni->size_lock, flags);
+ ni->allocated_size = le32_to_cpu(a->length) -
+ le16_to_cpu(a->data.resident.value_offset);
+ write_unlock_irqrestore(&ni->size_lock, flags);
+ if (new_data_size >= 0) {
+ BUG_ON(new_data_size < attr_len);
+ a->data.resident.value_length =
+ cpu_to_le32((u32)new_data_size);
+ }
+ goto flush_done;
+ }
+ /*
+ * We have to drop all the locks so we can call
+ * ntfs_attr_make_non_resident(). This could be optimised by try-
+ * locking the first page cache page and only if that fails dropping
+ * the locks, locking the page, and redoing all the locking and
+ * lookups. While this would be a huge optimisation, it is not worth
+ * it as this is definitely a slow code path.
+ */
+ ntfs_attr_put_search_ctx(ctx);
+ unmap_mft_record(base_ni);
+ up_write(&ni->runlist.lock);
+ /*
+ * Not enough space in the mft record, try to make the attribute
+ * non-resident and if successful restart the extension process.
+ */
+ err = ntfs_attr_make_non_resident(ni, attr_len);
+ if (likely(!err))
+ goto retry_extend;
+ /*
+ * Could not make non-resident. If this is due to this not being
+ * permitted for this attribute type or there not being enough space,
+ * try to make other attributes non-resident. Otherwise fail.
+ */
+ if (unlikely(err != -EPERM && err != -ENOSPC)) {
+ /* Only emit errors when the write will fail completely. */
+ read_lock_irqsave(&ni->size_lock, flags);
+ allocated_size = ni->allocated_size;
+ read_unlock_irqrestore(&ni->size_lock, flags);
+ if (start < 0 || start >= allocated_size)
+ ntfs_error(vol->sb, "Cannot extend allocation of "
+ "inode 0x%lx, attribute type 0x%x, "
+ "because the conversion from resident "
+ "to non-resident attribute failed "
+ "with error code %i.", vi->i_ino,
+ (unsigned)le32_to_cpu(ni->type), err);
+ if (err != -ENOMEM)
+ err = -EIO;
+ goto conv_err_out;
+ }
+ /* TODO: Not implemented from here, abort. */
+ read_lock_irqsave(&ni->size_lock, flags);
+ allocated_size = ni->allocated_size;
+ read_unlock_irqrestore(&ni->size_lock, flags);
+ if (start < 0 || start >= allocated_size) {
+ if (err == -ENOSPC)
+ ntfs_error(vol->sb, "Not enough space in the mft "
+ "record/on disk for the non-resident "
+ "attribute value. This case is not "
+ "implemented yet.");
+ else /* if (err == -EPERM) */
+ ntfs_error(vol->sb, "This attribute type may not be "
+ "non-resident. This case is not "
+ "implemented yet.");
+ }
+ err = -EOPNOTSUPP;
+ goto conv_err_out;
+#if 0
+ // TODO: Attempt to make other attributes non-resident.
+ if (!err)
+ goto do_resident_extend;
+ /*
+ * Both the attribute list attribute and the standard information
+ * attribute must remain in the base inode. Thus, if this is one of
+ * these attributes, we have to try to move other attributes out into
+ * extent mft records instead.
+ */
+ if (ni->type == AT_ATTRIBUTE_LIST ||
+ ni->type == AT_STANDARD_INFORMATION) {
+ // TODO: Attempt to move other attributes into extent mft
+ // records.
+ err = -EOPNOTSUPP;
+ if (!err)
+ goto do_resident_extend;
+ goto err_out;
+ }
+ // TODO: Attempt to move this attribute to an extent mft record, but
+ // only if it is not already the only attribute in an mft record in
+ // which case there would be nothing to gain.
+ err = -EOPNOTSUPP;
+ if (!err)
+ goto do_resident_extend;
+ /* There is nothing we can do to make enough space. )-: */
+ goto err_out;
+#endif
+do_non_resident_extend:
+ BUG_ON(!NInoNonResident(ni));
+ if (new_alloc_size == allocated_size) {
+ BUG_ON(vcn);
+ goto alloc_done;
+ }
+ /*
+ * If the data starts after the end of the old allocation, this is a
+ * $DATA attribute and sparse attributes are enabled on the volume and
+ * for this inode, then create a sparse region between the old
+ * allocated size and the start of the data. Otherwise simply proceed
+ * with filling the whole space between the old allocated size and the
+ * new allocated size with clusters.
+ */
+ if ((start >= 0 && start <= allocated_size) || ni->type != AT_DATA ||
+ !NVolSparseEnabled(vol) || NInoSparseDisabled(ni))
+ goto skip_sparse;
+ // TODO: This is not implemented yet. We just fill in with real
+ // clusters for now...
+ ntfs_debug("Inserting holes is not-implemented yet. Falling back to "
+ "allocating real clusters instead.");
+skip_sparse:
+ rl = ni->runlist.rl;
+ if (likely(rl)) {
+ /* Seek to the end of the runlist. */
+ while (rl->length)
+ rl++;
+ }
+ /* If this attribute extent is not mapped, map it now. */
+ if (unlikely(!rl || rl->lcn == LCN_RL_NOT_MAPPED ||
+ (rl->lcn == LCN_ENOENT && rl > ni->runlist.rl &&
+ (rl-1)->lcn == LCN_RL_NOT_MAPPED))) {
+ if (!rl && !allocated_size)
+ goto first_alloc;
+ rl = ntfs_mapping_pairs_decompress(vol, a, ni->runlist.rl);
+ if (IS_ERR(rl)) {
+ err = PTR_ERR(rl);
+ if (start < 0 || start >= allocated_size)
+ ntfs_error(vol->sb, "Cannot extend allocation "
+ "of inode 0x%lx, attribute "
+ "type 0x%x, because the "
+ "mapping of a runlist "
+ "fragment failed with error "
+ "code %i.", vi->i_ino,
+ (unsigned)le32_to_cpu(ni->type),
+ err);
+ if (err != -ENOMEM)
+ err = -EIO;
+ goto err_out;
+ }
+ ni->runlist.rl = rl;
+ /* Seek to the end of the runlist. */
+ while (rl->length)
+ rl++;
+ }
+ /*
+ * We now know the runlist of the last extent is mapped and @rl is at
+ * the end of the runlist. We want to begin allocating clusters
+ * starting at the last allocated cluster to reduce fragmentation. If
+ * there are no valid LCNs in the attribute we let the cluster
+ * allocator choose the starting cluster.
+ */
+ /* If the last LCN is a hole or simillar seek back to last real LCN. */
+ while (rl->lcn < 0 && rl > ni->runlist.rl)
+ rl--;
+first_alloc:
+ // FIXME: Need to implement partial allocations so at least part of the
+ // write can be performed when start >= 0. (Needed for POSIX write(2)
+ // conformance.)
+ rl2 = ntfs_cluster_alloc(vol, allocated_size >> vol->cluster_size_bits,
+ (new_alloc_size - allocated_size) >>
+ vol->cluster_size_bits, (rl && (rl->lcn >= 0)) ?
+ rl->lcn + rl->length : -1, DATA_ZONE, TRUE);
+ if (IS_ERR(rl2)) {
+ err = PTR_ERR(rl2);
+ if (start < 0 || start >= allocated_size)
+ ntfs_error(vol->sb, "Cannot extend allocation of "
+ "inode 0x%lx, attribute type 0x%x, "
+ "because the allocation of clusters "
+ "failed with error code %i.", vi->i_ino,
+ (unsigned)le32_to_cpu(ni->type), err);
+ if (err != -ENOMEM && err != -ENOSPC)
+ err = -EIO;
+ goto err_out;
+ }
+ rl = ntfs_runlists_merge(ni->runlist.rl, rl2);
+ if (IS_ERR(rl)) {
+ err = PTR_ERR(rl);
+ if (start < 0 || start >= allocated_size)
+ ntfs_error(vol->sb, "Cannot extend allocation of "
+ "inode 0x%lx, attribute type 0x%x, "
+ "because the runlist merge failed "
+ "with error code %i.", vi->i_ino,
+ (unsigned)le32_to_cpu(ni->type), err);
+ if (err != -ENOMEM)
+ err = -EIO;
+ if (ntfs_cluster_free_from_rl(vol, rl2)) {
+ ntfs_error(vol->sb, "Failed to release allocated "
+ "cluster(s) in error code path. Run "
+ "chkdsk to recover the lost "
+ "cluster(s).");
+ NVolSetErrors(vol);
+ }
+ ntfs_free(rl2);
+ goto err_out;
+ }
+ ni->runlist.rl = rl;
+ ntfs_debug("Allocated 0x%llx clusters.", (long long)(new_alloc_size -
+ allocated_size) >> vol->cluster_size_bits);
+ /* Find the runlist element with which the attribute extent starts. */
+ ll = sle64_to_cpu(a->data.non_resident.lowest_vcn);
+ rl2 = ntfs_rl_find_vcn_nolock(rl, ll);
+ BUG_ON(!rl2);
+ BUG_ON(!rl2->length);
+ BUG_ON(rl2->lcn < LCN_HOLE);
+ mp_rebuilt = FALSE;
+ /* Get the size for the new mapping pairs array for this extent. */
+ mp_size = ntfs_get_size_for_mapping_pairs(vol, rl2, ll, -1);
+ if (unlikely(mp_size <= 0)) {
+ err = mp_size;
+ if (start < 0 || start >= allocated_size)
+ ntfs_error(vol->sb, "Cannot extend allocation of "
+ "inode 0x%lx, attribute type 0x%x, "
+ "because determining the size for the "
+ "mapping pairs failed with error code "
+ "%i.", vi->i_ino,
+ (unsigned)le32_to_cpu(ni->type), err);
+ err = -EIO;
+ goto undo_alloc;
+ }
+ /* Extend the attribute record to fit the bigger mapping pairs array. */
+ attr_len = le32_to_cpu(a->length);
+ err = ntfs_attr_record_resize(m, a, mp_size +
+ le16_to_cpu(a->data.non_resident.mapping_pairs_offset));
+ if (unlikely(err)) {
+ BUG_ON(err != -ENOSPC);
+ // TODO: Deal with this by moving this extent to a new mft
+ // record or by starting a new extent in a new mft record,
+ // possibly by extending this extent partially and filling it
+ // and creating a new extent for the remainder, or by making
+ // other attributes non-resident and/or by moving other
+ // attributes out of this mft record.
+ if (start < 0 || start >= allocated_size)
+ ntfs_error(vol->sb, "Not enough space in the mft "
+ "record for the extended attribute "
+ "record. This case is not "
+ "implemented yet.");
+ err = -EOPNOTSUPP;
+ goto undo_alloc;
+ }
+ mp_rebuilt = TRUE;
+ /* Generate the mapping pairs array directly into the attr record. */
+ err = ntfs_mapping_pairs_build(vol, (u8*)a +
+ le16_to_cpu(a->data.non_resident.mapping_pairs_offset),
+ mp_size, rl2, ll, -1, NULL);
+ if (unlikely(err)) {
+ if (start < 0 || start >= allocated_size)
+ ntfs_error(vol->sb, "Cannot extend allocation of "
+ "inode 0x%lx, attribute type 0x%x, "
+ "because building the mapping pairs "
+ "failed with error code %i.", vi->i_ino,
+ (unsigned)le32_to_cpu(ni->type), err);
+ err = -EIO;
+ goto undo_alloc;
+ }
+ /* Update the highest_vcn. */
+ a->data.non_resident.highest_vcn = cpu_to_sle64((new_alloc_size >>
+ vol->cluster_size_bits) - 1);
+ /*
+ * We now have extended the allocated size of the attribute. Reflect
+ * this in the ntfs_inode structure and the attribute record.
+ */
+ if (a->data.non_resident.lowest_vcn) {
+ /*
+ * We are not in the first attribute extent, switch to it, but
+ * first ensure the changes will make it to disk later.
+ */
+ flush_dcache_mft_record_page(ctx->ntfs_ino);
+ mark_mft_record_dirty(ctx->ntfs_ino);
+ ntfs_attr_reinit_search_ctx(ctx);
+ err = ntfs_attr_lookup(ni->type, ni->name, ni->name_len,
+ CASE_SENSITIVE, 0, NULL, 0, ctx);
+ if (unlikely(err))
+ goto restore_undo_alloc;
+ /* @m is not used any more so no need to set it. */
+ a = ctx->attr;
+ }
+ write_lock_irqsave(&ni->size_lock, flags);
+ ni->allocated_size = new_alloc_size;
+ a->data.non_resident.allocated_size = cpu_to_sle64(new_alloc_size);
+ /*
+ * FIXME: This would fail if @ni is a directory, $MFT, or an index,
+ * since those can have sparse/compressed set. For example can be
+ * set compressed even though it is not compressed itself and in that
+ * case the bit means that files are to be created compressed in the
+ * directory... At present this is ok as this code is only called for
+ * regular files, and only for their $DATA attribute(s).
+ * FIXME: The calculation is wrong if we created a hole above. For now
+ * it does not matter as we never create holes.
+ */
+ if (NInoSparse(ni) || NInoCompressed(ni)) {
+ ni->itype.compressed.size += new_alloc_size - allocated_size;
+ a->data.non_resident.compressed_size =
+ cpu_to_sle64(ni->itype.compressed.size);
+ vi->i_blocks = ni->itype.compressed.size >> 9;
+ } else
+ vi->i_blocks = new_alloc_size >> 9;
+ write_unlock_irqrestore(&ni->size_lock, flags);
+alloc_done:
+ if (new_data_size >= 0) {
+ BUG_ON(new_data_size <
+ sle64_to_cpu(a->data.non_resident.data_size));
+ a->data.non_resident.data_size = cpu_to_sle64(new_data_size);
+ }
+flush_done:
+ /* Ensure the changes make it to disk. */
+ flush_dcache_mft_record_page(ctx->ntfs_ino);
+ mark_mft_record_dirty(ctx->ntfs_ino);
+done:
+ ntfs_attr_put_search_ctx(ctx);
+ unmap_mft_record(base_ni);
+ up_write(&ni->runlist.lock);
+ ntfs_debug("Done, new_allocated_size 0x%llx.",
+ (unsigned long long)new_alloc_size);
+ return new_alloc_size;
+restore_undo_alloc:
+ if (start < 0 || start >= allocated_size)
+ ntfs_error(vol->sb, "Cannot complete extension of allocation "
+ "of inode 0x%lx, attribute type 0x%x, because "
+ "lookup of first attribute extent failed with "
+ "error code %i.", vi->i_ino,
+ (unsigned)le32_to_cpu(ni->type), err);
+ if (err == -ENOENT)
+ err = -EIO;
+ ntfs_attr_reinit_search_ctx(ctx);
+ if (ntfs_attr_lookup(ni->type, ni->name, ni->name_len, CASE_SENSITIVE,
+ allocated_size >> vol->cluster_size_bits, NULL, 0,
+ ctx)) {
+ ntfs_error(vol->sb, "Failed to find last attribute extent of "
+ "attribute in error code path. Run chkdsk to "
+ "recover.");
+ write_lock_irqsave(&ni->size_lock, flags);
+ ni->allocated_size = new_alloc_size;
+ /*
+ * FIXME: This would fail if @ni is a directory... See above.
+ * FIXME: The calculation is wrong if we created a hole above.
+ * For now it does not matter as we never create holes.
+ */
+ if (NInoSparse(ni) || NInoCompressed(ni)) {
+ ni->itype.compressed.size += new_alloc_size -
+ allocated_size;
+ vi->i_blocks = ni->itype.compressed.size >> 9;
+ } else
+ vi->i_blocks = new_alloc_size >> 9;
+ write_unlock_irqrestore(&ni->size_lock, flags);
+ ntfs_attr_put_search_ctx(ctx);
+ unmap_mft_record(base_ni);
+ up_write(&ni->runlist.lock);
+ /*
+ * The only thing that is now wrong is the allocated size of the
+ * base attribute extent which chkdsk should be able to fix.
+ */
+ NVolSetErrors(vol);
+ return err;
+ }
+ ctx->attr->data.non_resident.highest_vcn = cpu_to_sle64(
+ (allocated_size >> vol->cluster_size_bits) - 1);
+undo_alloc:
+ ll = allocated_size >> vol->cluster_size_bits;
+ if (ntfs_cluster_free(ni, ll, -1, ctx) < 0) {
+ ntfs_error(vol->sb, "Failed to release allocated cluster(s) "
+ "in error code path. Run chkdsk to recover "
+ "the lost cluster(s).");
+ NVolSetErrors(vol);
+ }
+ m = ctx->mrec;
+ a = ctx->attr;
+ /*
+ * If the runlist truncation fails and/or the search context is no
+ * longer valid, we cannot resize the attribute record or build the
+ * mapping pairs array thus we mark the inode bad so that no access to
+ * the freed clusters can happen.
+ */
+ if (ntfs_rl_truncate_nolock(vol, &ni->runlist, ll) || IS_ERR(m)) {
+ ntfs_error(vol->sb, "Failed to %s in error code path. Run "
+ "chkdsk to recover.", IS_ERR(m) ?
+ "restore attribute search context" :
+ "truncate attribute runlist");
+ NVolSetErrors(vol);
+ } else if (mp_rebuilt) {
+ if (ntfs_attr_record_resize(m, a, attr_len)) {
+ ntfs_error(vol->sb, "Failed to restore attribute "
+ "record in error code path. Run "
+ "chkdsk to recover.");
+ NVolSetErrors(vol);
+ } else /* if (success) */ {
+ if (ntfs_mapping_pairs_build(vol, (u8*)a + le16_to_cpu(
+ a->data.non_resident.
+ mapping_pairs_offset), attr_len -
+ le16_to_cpu(a->data.non_resident.
+ mapping_pairs_offset), rl2, ll, -1,
+ NULL)) {
+ ntfs_error(vol->sb, "Failed to restore "
+ "mapping pairs array in error "
+ "code path. Run chkdsk to "
+ "recover.");
+ NVolSetErrors(vol);
+ }
+ flush_dcache_mft_record_page(ctx->ntfs_ino);
+ mark_mft_record_dirty(ctx->ntfs_ino);
+ }
+ }
+err_out:
+ if (ctx)
+ ntfs_attr_put_search_ctx(ctx);
+ if (m)
+ unmap_mft_record(base_ni);
+ up_write(&ni->runlist.lock);
+conv_err_out:
+ ntfs_debug("Failed. Returning error code %i.", err);
+ return err;
+}
+
/**
* ntfs_attr_set - fill (a part of) an attribute with a byte
* @ni: ntfs inode describing the attribute to fill
* byte offset @ofs inside the attribute with the constant byte @val.
*
* This function is effectively like memset() applied to an ntfs attribute.
+ * Note thie function actually only operates on the page cache pages belonging
+ * to the ntfs attribute and it marks them dirty after doing the memset().
+ * Thus it relies on the vm dirty page write code paths to cause the modified
+ * pages to be written to the mft record/disk.
*
* Return 0 on success and -errno on error. An error code of -ESPIPE means
* that @ofs + @cnt were outside the end of the attribute and no write was
BUG_ON(cnt < 0);
if (!cnt)
goto done;
+ /*
+ * FIXME: Compressed and encrypted attributes are not supported when
+ * writing and we should never have gotten here for them.
+ */
+ BUG_ON(NInoCompressed(ni));
+ BUG_ON(NInoEncrypted(ni));
mapping = VFS_I(ni)->i_mapping;
/* Work out the starting index and page offset. */
idx = ofs >> PAGE_CACHE_SHIFT;
end = ofs + cnt;
end_ofs = end & ~PAGE_CACHE_MASK;
/* If the end is outside the inode size return -ESPIPE. */
- if (unlikely(end > VFS_I(ni)->i_size)) {
+ if (unlikely(end > i_size_read(VFS_I(ni)))) {
ntfs_error(vol->sb, "Request exceeds end of attribute.");
return -ESPIPE;
}
/* Finally unlock and release the page. */
unlock_page(page);
page_cache_release(page);
+ balance_dirty_pages_ratelimited(mapping);
+ cond_resched();
}
/* If there is a last partial page, need to do it the slow way. */
if (end_ofs) {
ntfs_debug("Done.");
return 0;
}
+
+#endif /* NTFS_RW */
git://git.onelab.eu / linux-2.6.git / blobdiff