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diff --git a/docs/specs/acpi_pci_hotplug.txt b/docs/specs/acpi_pci_hotplug.txt
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+QEMU<->ACPI BIOS PCI hotplug interface
+--------------------------------------
+
+QEMU supports PCI hotplug via ACPI, for PCI bus 0. This document
+describes the interface between QEMU and the ACPI BIOS.
+
+ACPI GPE block (IO ports 0xafe0-0xafe3, byte access):
+-----------------------------------------
+
+Generic ACPI GPE block. Bit 1 (GPE.1) used to notify PCI hotplug/eject
+event to ACPI BIOS, via SCI interrupt.
+
+PCI slot injection notification pending (IO port 0xae00-0xae03, 4-byte access):
+---------------------------------------------------------------
+Slot injection notification pending. One bit per slot.
+
+Read by ACPI BIOS GPE.1 handler to notify OS of injection
+events.
+
+PCI slot removal notification (IO port 0xae04-0xae07, 4-byte access):
+-----------------------------------------------------
+Slot removal notification pending. One bit per slot.
+
+Read by ACPI BIOS GPE.1 handler to notify OS of removal
+events.
+
+PCI device eject (IO port 0xae08-0xae0b, 4-byte access):
+----------------------------------------
+
+Used by ACPI BIOS _EJ0 method to request device removal. One bit per slot.
+Reads return 0.
+
+PCI removability status (IO port 0xae0c-0xae0f, 4-byte access):
+-----------------------------------------------
+
+Used by ACPI BIOS _RMV method to indicate removability status to OS. One
+bit per slot.
diff --git a/docs/specs/ivshmem_device_spec.txt b/docs/specs/ivshmem_device_spec.txt
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+
+Device Specification for Inter-VM shared memory device
+------------------------------------------------------
+
+The Inter-VM shared memory device is designed to share a region of memory to
+userspace in multiple virtual guests.  The memory region does not belong to any
+guest, but is a POSIX memory object on the host.  Optionally, the device may
+support sending interrupts to other guests sharing the same memory region.
+
+
+The Inter-VM PCI device
+-----------------------
+
+*BARs*
+
+The device supports three BARs.  BAR0 is a 1 Kbyte MMIO region to support
+registers.  BAR1 is used for MSI-X when it is enabled in the device.  BAR2 is
+used to map the shared memory object from the host.  The size of BAR2 is
+specified when the guest is started and must be a power of 2 in size.
+
+*Registers*
+
+The device currently supports 4 registers of 32-bits each.  Registers
+are used for synchronization between guests sharing the same memory object when
+interrupts are supported (this requires using the shared memory server).
+
+The server assigns each VM an ID number and sends this ID number to the Qemu
+process when the guest starts.
+
+enum ivshmem_registers {
+    IntrMask = 0,
+    IntrStatus = 4,
+    IVPosition = 8,
+    Doorbell = 12
+};
+
+The first two registers are the interrupt mask and status registers.  Mask and
+status are only used with pin-based interrupts.  They are unused with MSI
+interrupts.
+
+Status Register: The status register is set to 1 when an interrupt occurs.
+
+Mask Register: The mask register is bitwise ANDed with the interrupt status
+and the result will raise an interrupt if it is non-zero.  However, since 1 is
+the only value the status will be set to, it is only the first bit of the mask
+that has any effect.  Therefore interrupts can be masked by setting the first
+bit to 0 and unmasked by setting the first bit to 1.
+
+IVPosition Register: The IVPosition register is read-only and reports the
+guest's ID number.  The guest IDs are non-negative integers.  When using the
+server, since the server is a separate process, the VM ID will only be set when
+the device is ready (shared memory is received from the server and accessible via
+the device).  If the device is not ready, the IVPosition will return -1.
+Applications should ensure that they have a valid VM ID before accessing the
+shared memory.
+
+Doorbell Register:  To interrupt another guest, a guest must write to the
+Doorbell register.  The doorbell register is 32-bits, logically divided into
+two 16-bit fields.  The high 16-bits are the guest ID to interrupt and the low
+16-bits are the interrupt vector to trigger.  The semantics of the value
+written to the doorbell depends on whether the device is using MSI or a regular
+pin-based interrupt.  In short, MSI uses vectors while regular interrupts set the
+status register.
+
+Regular Interrupts
+
+If regular interrupts are used (due to either a guest not supporting MSI or the
+user specifying not to use them on startup) then the value written to the lower
+16-bits of the Doorbell register results is arbitrary and will trigger an
+interrupt in the destination guest.
+
+Message Signalled Interrupts
+
+A ivshmem device may support multiple MSI vectors.  If so, the lower 16-bits
+written to the Doorbell register must be between 0 and the maximum number of
+vectors the guest supports.  The lower 16 bits written to the doorbell is the
+MSI vector that will be raised in the destination guest.  The number of MSI
+vectors is configurable but it is set when the VM is started.
+
+The important thing to remember with MSI is that it is only a signal, no status
+is set (since MSI interrupts are not shared).  All information other than the
+interrupt itself should be communicated via the shared memory region.  Devices
+supporting multiple MSI vectors can use different vectors to indicate different
+events have occurred.  The semantics of interrupt vectors are left to the
+user's discretion.
+
+
+Usage in the Guest
+------------------
+
+The shared memory device is intended to be used with the provided UIO driver.
+Very little configuration is needed.  The guest should map BAR0 to access the
+registers (an array of 32-bit ints allows simple writing) and map BAR2 to
+access the shared memory region itself.  The size of the shared memory region
+is specified when the guest (or shared memory server) is started.  A guest may
+map the whole shared memory region or only part of it.
diff --git a/docs/specs/qed_spec.txt b/docs/specs/qed_spec.txt
new file mode 100644
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+=Specification=
+
+The file format looks like this:
+
+ +----------+----------+----------+-----+
+ | cluster0 | cluster1 | cluster2 | ... |
+ +----------+----------+----------+-----+
+
+The first cluster begins with the '''header'''.  The header contains information about where regular clusters start; this allows the header to be extensible and store extra information about the image file.  A regular cluster may be a '''data cluster''', an '''L2''', or an '''L1 table'''.  L1 and L2 tables are composed of one or more contiguous clusters.
+
+Normally the file size will be a multiple of the cluster size.  If the file size is not a multiple, extra information after the last cluster may not be preserved if data is written.  Legitimate extra information should use space between the header and the first regular cluster.
+
+All fields are little-endian.
+
+==Header==
+ Header {
+     uint32_t magic;               /* QED\0 */
+ 
+     uint32_t cluster_size;        /* in bytes */
+     uint32_t table_size;          /* for L1 and L2 tables, in clusters */
+     uint32_t header_size;         /* in clusters */
+ 
+     uint64_t features;            /* format feature bits */
+     uint64_t compat_features;     /* compat feature bits */
+     uint64_t autoclear_features;  /* self-resetting feature bits */
+
+     uint64_t l1_table_offset;     /* in bytes */
+     uint64_t image_size;          /* total logical image size, in bytes */
+ 
+     /* if (features & QED_F_BACKING_FILE) */
+     uint32_t backing_filename_offset; /* in bytes from start of header */
+     uint32_t backing_filename_size;   /* in bytes */
+ }
+
+Field descriptions:
+* ''cluster_size'' must be a power of 2 in range [2^12, 2^26].
+* ''table_size'' must be a power of 2 in range [1, 16].
+* ''header_size'' is the number of clusters used by the header and any additional information stored before regular clusters.
+* ''features'', ''compat_features'', and ''autoclear_features'' are file format extension bitmaps.  They work as follows:
+** An image with unknown ''features'' bits enabled must not be opened.  File format changes that are not backwards-compatible must use ''features'' bits.
+** An image with unknown ''compat_features'' bits enabled can be opened safely.  The unknown features are simply ignored and represent backwards-compatible changes to the file format.
+** An image with unknown ''autoclear_features'' bits enable can be opened safely after clearing the unknown bits.  This allows for backwards-compatible changes to the file format which degrade gracefully and can be re-enabled again by a new program later.
+* ''l1_table_offset'' is the offset of the first byte of the L1 table in the image file and must be a multiple of ''cluster_size''.
+* ''image_size'' is the block device size seen by the guest and must be a multiple of 512 bytes.
+* ''backing_filename_offset'' and ''backing_filename_size'' describe a string in (byte offset, byte size) form.  It is not NUL-terminated and has no alignment constraints.  The string must be stored within the first ''header_size'' clusters.  The backing filename may be an absolute path or relative to the image file.
+
+Feature bits:
+* QED_F_BACKING_FILE = 0x01.  The image uses a backing file.
+* QED_F_NEED_CHECK = 0x02.  The image needs a consistency check before use.
+* QED_F_BACKING_FORMAT_NO_PROBE = 0x04.  The backing file is a raw disk image and no file format autodetection should be attempted.  This should be used to ensure that raw backing files are never detected as an image format if they happen to contain magic constants.
+
+There are currently no defined ''compat_features'' or ''autoclear_features'' bits.
+
+Fields predicated on a feature bit are only used when that feature is set.  The fields always take up header space, regardless of whether or not the feature bit is set.
+
+==Tables==
+
+Tables provide the translation from logical offsets in the block device to cluster offsets in the file.
+
+ #define TABLE_NOFFSETS (table_size * cluster_size / sizeof(uint64_t))
+  
+ Table {
+     uint64_t offsets[TABLE_NOFFSETS];
+ }
+
+The tables are organized as follows:
+
+                    +----------+
+                    | L1 table |
+                    +----------+
+               ,------'  |  '------.
+          +----------+   |    +----------+
+          | L2 table |  ...   | L2 table |
+          +----------+        +----------+
+      ,------'  |  '------.
+ +----------+   |    +----------+
+ |   Data   |  ...   |   Data   |
+ +----------+        +----------+
+
+A table is made up of one or more contiguous clusters.  The table_size header field determines table size for an image file.  For example, cluster_size=64 KB and table_size=4 results in 256 KB tables.
+
+The logical image size must be less than or equal to the maximum possible size of clusters rooted by the L1 table:
+ header.image_size <= TABLE_NOFFSETS * TABLE_NOFFSETS * header.cluster_size
+
+L1, L2, and data cluster offsets must be aligned to header.cluster_size.  The following offsets have special meanings:
+
+===L2 table offsets===
+* 0 - unallocated.  The L2 table is not yet allocated.
+
+===Data cluster offsets===
+* 0 - unallocated.  The data cluster is not yet allocated.
+
+Future format extensions may wish to store per-offset information.  The least significant 12 bits of an offset are reserved for this purpose and must be set to zero.  Image files with cluster_size > 2^12 will have more unused bits which should also be zeroed.
+
+===Unallocated L2 tables and data clusters===
+Reads to an unallocated area of the image file access the backing file.  If there is no backing file, then zeroes are produced.  The backing file may be smaller than the image file and reads of unallocated areas beyond the end of the backing file produce zeroes.
+
+Writes to an unallocated area cause a new data clusters to be allocated, and a new L2 table if that is also unallocated.  The new data cluster is populated with data from the backing file (or zeroes if no backing file) and the data being written.
+
+===Logical offset translation===
+Logical offsets are translated into cluster offsets as follows:
+
+  table_bits table_bits    cluster_bits
+  <--------> <--------> <--------------->
+ +----------+----------+-----------------+
+ | L1 index | L2 index |     byte offset |
+ +----------+----------+-----------------+
+ 
+       Structure of a logical offset
+
+ offset_mask = ~(cluster_size - 1) # mask for the image file byte offset
+ 
+ def logical_to_cluster_offset(l1_index, l2_index, byte_offset):
+   l2_offset = l1_table[l1_index]
+   l2_table = load_table(l2_offset)
+   cluster_offset = l2_table[l2_index] & offset_mask
+   return cluster_offset + byte_offset
+
+==Consistency checking==
+
+This section is informational and included to provide background on the use of the QED_F_NEED_CHECK ''features'' bit.
+
+The QED_F_NEED_CHECK bit is used to mark an image as dirty before starting an operation that could leave the image in an inconsistent state if interrupted by a crash or power failure.  A dirty image must be checked on open because its metadata may not be consistent.
+
+Consistency check includes the following invariants:
+# Each cluster is referenced once and only once.  It is an inconsistency to have a cluster referenced more than once by L1 or L2 tables.  A cluster has been leaked if it has no references.
+# Offsets must be within the image file size and must be ''cluster_size'' aligned.
+# Table offsets must at least ''table_size'' * ''cluster_size'' bytes from the end of the image file so that there is space for the entire table.
+
+The consistency check process starts by from ''l1_table_offset'' and scans all L2 tables.  After the check completes with no other errors besides leaks, the QED_F_NEED_CHECK bit can be cleared and the image can be accessed.