summaryrefslogtreecommitdiffstats
path: root/module/zfs/sa.c
diff options
context:
space:
mode:
Diffstat (limited to 'module/zfs/sa.c')
-rw-r--r--module/zfs/sa.c85
1 files changed, 44 insertions, 41 deletions
diff --git a/module/zfs/sa.c b/module/zfs/sa.c
index 25b4da9f8..9063d1dae 100644
--- a/module/zfs/sa.c
+++ b/module/zfs/sa.c
@@ -538,20 +538,30 @@ sa_copy_data(sa_data_locator_t *func, void *datastart, void *target, int buflen)
}
/*
- * Determine several different sizes
- * first the sa header size
- * the number of bytes to be stored
- * if spill would occur the index in the attribute array is returned
+ * Determine several different values pertaining to system attribute
+ * buffers.
*
- * the boolean will_spill will be set when spilling is necessary. It
- * is only set when the buftype is SA_BONUS
+ * Return the size of the sa_hdr_phys_t header for the buffer. Each
+ * variable length attribute except the first contributes two bytes to
+ * the header size, which is then rounded up to an 8-byte boundary.
+ *
+ * The following output parameters are also computed.
+ *
+ * index - The index of the first attribute in attr_desc that will
+ * spill over. Only valid if will_spill is set.
+ *
+ * total - The total number of bytes of all system attributes described
+ * in attr_desc.
+ *
+ * will_spill - Set when spilling is necessary. It is only set when
+ * the buftype is SA_BONUS.
*/
static int
sa_find_sizes(sa_os_t *sa, sa_bulk_attr_t *attr_desc, int attr_count,
dmu_buf_t *db, sa_buf_type_t buftype, int *index, int *total,
boolean_t *will_spill)
{
- int var_size = 0;
+ int var_size_count = 0;
int i;
int full_space;
int hdrsize;
@@ -577,6 +587,7 @@ sa_find_sizes(sa_os_t *sa, sa_bulk_attr_t *attr_desc, int attr_count,
for (i = 0; i != attr_count; i++) {
boolean_t is_var_sz, might_spill_here;
+ int tmp_hdrsize;
*total = P2ROUNDUP(*total, 8);
*total += attr_desc[i].sa_length;
@@ -584,31 +595,35 @@ sa_find_sizes(sa_os_t *sa, sa_bulk_attr_t *attr_desc, int attr_count,
continue;
is_var_sz = (SA_REGISTERED_LEN(sa, attr_desc[i].sa_attr) == 0);
- if (is_var_sz) {
- var_size++;
- }
+ if (is_var_sz)
+ var_size_count++;
+
+ /*
+ * Calculate what the SA header size would be if this
+ * attribute doesn't spill.
+ */
+ tmp_hdrsize = hdrsize + ((is_var_sz && var_size_count > 1) ?
+ sizeof (uint16_t) : 0);
+ /*
+ * Check whether this attribute spans into the space
+ * that would be used by the spill block pointer should
+ * a spill block be needed.
+ */
might_spill_here =
buftype == SA_BONUS && *index == -1 &&
- (*total + P2ROUNDUP(hdrsize, 8)) >
+ (*total + P2ROUNDUP(tmp_hdrsize, 8)) >
(full_space - sizeof (blkptr_t));
- if (is_var_sz && var_size > 1) {
- /*
- * Don't worry that the spill block might overflow.
- * It will be resized if needed in sa_build_layouts().
- */
+ if (is_var_sz && var_size_count > 1) {
if (buftype == SA_SPILL ||
- P2ROUNDUP(hdrsize + sizeof (uint16_t), 8) +
- *total < full_space) {
+ tmp_hdrsize + *total < full_space) {
/*
- * Account for header space used by array of
- * optional sizes of variable-length attributes.
* Record the extra header size in case this
* increase needs to be reversed due to
* spill-over.
*/
- hdrsize += sizeof (uint16_t);
+ hdrsize = tmp_hdrsize;
if (*index != -1 || might_spill_here)
extra_hdrsize += sizeof (uint16_t);
} else {
@@ -621,10 +636,9 @@ sa_find_sizes(sa_os_t *sa, sa_bulk_attr_t *attr_desc, int attr_count,
}
/*
- * find index of where spill *could* occur.
- * Then continue to count of remainder attribute
- * space. The sum is used later for sizing bonus
- * and spill buffer.
+ * Store index of where spill *could* occur. Then
+ * continue to count the remaining attribute sizes. The
+ * sum is used later for sizing bonus and spill buffer.
*/
if (might_spill_here)
*index = i;
@@ -657,9 +671,9 @@ sa_build_layouts(sa_handle_t *hdl, sa_bulk_attr_t *attr_desc, int attr_count,
sa_buf_type_t buftype;
sa_hdr_phys_t *sahdr;
void *data_start;
- int buf_space;
sa_attr_type_t *attrs, *attrs_start;
int i, lot_count;
+ int spill_idx;
int hdrsize;
int spillhdrsize = 0;
int used;
@@ -674,7 +688,7 @@ sa_build_layouts(sa_handle_t *hdl, sa_bulk_attr_t *attr_desc, int attr_count,
/* first determine bonus header size and sum of all attributes */
hdrsize = sa_find_sizes(sa, attr_desc, attr_count, hdl->sa_bonus,
- SA_BONUS, &i, &used, &spilling);
+ SA_BONUS, &spill_idx, &used, &spilling);
if (used > SPA_MAXBLOCKSIZE)
return (SET_ERROR(EFBIG));
@@ -696,14 +710,13 @@ sa_build_layouts(sa_handle_t *hdl, sa_bulk_attr_t *attr_desc, int attr_count,
}
dmu_buf_will_dirty(hdl->sa_spill, tx);
- spillhdrsize = sa_find_sizes(sa, &attr_desc[i],
- attr_count - i, hdl->sa_spill, SA_SPILL, &i,
+ spillhdrsize = sa_find_sizes(sa, &attr_desc[spill_idx],
+ attr_count - spill_idx, hdl->sa_spill, SA_SPILL, &i,
&spill_used, &dummy);
if (spill_used > SPA_MAXBLOCKSIZE)
return (SET_ERROR(EFBIG));
- buf_space = hdl->sa_spill->db_size - spillhdrsize;
if (BUF_SPACE_NEEDED(spill_used, spillhdrsize) >
hdl->sa_spill->db_size)
VERIFY(0 == sa_resize_spill(hdl,
@@ -715,12 +728,6 @@ sa_build_layouts(sa_handle_t *hdl, sa_bulk_attr_t *attr_desc, int attr_count,
sahdr = (sa_hdr_phys_t *)hdl->sa_bonus->db_data;
buftype = SA_BONUS;
- if (spilling)
- buf_space = (sa->sa_force_spill) ?
- 0 : SA_BLKPTR_SPACE - hdrsize;
- else
- buf_space = hdl->sa_bonus->db_size - hdrsize;
-
attrs_start = attrs = kmem_alloc(sizeof (sa_attr_type_t) * attr_count,
KM_SLEEP);
lot_count = 0;
@@ -729,14 +736,12 @@ sa_build_layouts(sa_handle_t *hdl, sa_bulk_attr_t *attr_desc, int attr_count,
uint16_t length;
ASSERT(IS_P2ALIGNED(data_start, 8));
- ASSERT(IS_P2ALIGNED(buf_space, 8));
attrs[i] = attr_desc[i].sa_attr;
length = SA_REGISTERED_LEN(sa, attrs[i]);
if (length == 0)
length = attr_desc[i].sa_length;
- if (buf_space < length) { /* switch to spill buffer */
- VERIFY(spilling);
+ if (spilling && i == spill_idx) { /* switch to spill buffer */
VERIFY(bonustype == DMU_OT_SA);
if (buftype == SA_BONUS && !sa->sa_force_spill) {
sa_find_layout(hdl->sa_os, hash, attrs_start,
@@ -753,7 +758,6 @@ sa_build_layouts(sa_handle_t *hdl, sa_bulk_attr_t *attr_desc, int attr_count,
data_start = (void *)((uintptr_t)sahdr +
spillhdrsize);
attrs_start = &attrs[i];
- buf_space = hdl->sa_spill->db_size - spillhdrsize;
lot_count = 0;
}
hash ^= SA_ATTR_HASH(attrs[i]);
@@ -766,7 +770,6 @@ sa_build_layouts(sa_handle_t *hdl, sa_bulk_attr_t *attr_desc, int attr_count,
}
data_start = (void *)P2ROUNDUP(((uintptr_t)data_start +
length), 8);
- buf_space -= P2ROUNDUP(length, 8);
lot_count++;
}
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-26 11:54:15 +0000